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Hirata A, Akazawa Y, Kodera S, Otsuru N, Laakso I. Electric field envelope focality in superficial brain areas with linear alignment montage in temporal interference stimulation. Comput Biol Med 2024; 178:108697. [PMID: 38850958 DOI: 10.1016/j.compbiomed.2024.108697] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2024] [Revised: 05/13/2024] [Accepted: 06/01/2024] [Indexed: 06/10/2024]
Abstract
Temporal interference stimulation (TIS) uses two pairs of conventional transcranial alternating current stimulation (tACS) electrodes, each with a different frequency, to generate a time-varying electric field (EF) envelope (EFE). The EFE focality in primary somatosensory and motor cortex areas of a standard human brain was computed using newly defined linear alignment montages. Sixty head volume conductor models constructed from magnetic resonance images were considered to evaluate interindividual variability. Six TIS and two tACS electrode montages were considered, including linear and rectangular alignments. EFEs were computed using the scalar-potential finite-difference method. The computed EFE was projected onto the standard brain space for each montage. Computational results showed that TIS and tACS generated different EFE and EF distributions in postcentral and precentral gyri regions. For TIS, the EFE amplitude in the target areas had lower variability than the EF strength of tACS. However, bipolar tACS montages showed higher focality in the superficial postcentral and precentral gyri regions than in TIS. TIS generated greater EFE penetration than bipolar tACS at depths <5-10 mm below the brain surface. From group-level analysis, tACS with a bipolar montage was preferred for targets <5-10 mm in depth (gyral crowns) and TIS for deeper targets. TIS with a linear alignment montage could be an effective method for deep structures and sulcal walls. These findings provide valuable insights into the choice of TIS and tACS for stimulating specific brain regions.
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Affiliation(s)
- Akimasa Hirata
- Department of Electrical and Mechanical Engineering, Nagoya Institute of Technology, Nagoya, Japan; Center of Biomedical Physics and Information Technology, Nagoya Institute of Technology, Nagoya, Japan.
| | - Yusuke Akazawa
- Department of Electrical and Mechanical Engineering, Nagoya Institute of Technology, Nagoya, Japan
| | - Sachiko Kodera
- Department of Electrical and Mechanical Engineering, Nagoya Institute of Technology, Nagoya, Japan; Center of Biomedical Physics and Information Technology, Nagoya Institute of Technology, Nagoya, Japan
| | - Naofumi Otsuru
- Institute for Human Movement and Medical Sciences, Niigata University of Health and Welfare, Niigata, Japan
| | - Ilkka Laakso
- Department of Electrical Engineering and Automation, Aalto University, Espoo, Finland
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Liu X, Qi S, Hou L, Liu Y, Wang X. Noninvasive Deep Brain Stimulation via Temporal Interference Electric Fields Enhanced Motor Performance of Mice and Its Neuroplasticity Mechanisms. Mol Neurobiol 2024; 61:3314-3329. [PMID: 37987957 DOI: 10.1007/s12035-023-03721-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2023] [Accepted: 10/17/2023] [Indexed: 11/22/2023]
Abstract
A noninvasive deep brain stimulation via temporal interference (TI) electric fields is a novel neuromodulation technology, but few advances about TI stimulation effectiveness and mechanisms have been reported. One hundred twenty-six mice were selected for the experiment by power analysis. In the present study, TI stimulation was proved to stimulate noninvasively primary motor cortex (M1) of mice, and 7-day TI stimulation with an envelope frequency of 20 Hz (∆f =20 Hz), instead of an envelope frequency of 10 Hz (∆f =10 Hz), could obviously improve mice motor performance. The mechanism of action may be related to enhancing the strength of synaptic connections, improving synaptic transmission efficiency, increasing dendritic spine density, promoting neurotransmitter release, and increasing the expression and activity of synapse-related proteins, such as brain-derived neurotrophic factor (BDNF), postsynaptic density protein-95 (PSD-95), and glutamate receptor protein. Furthermore, the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT) signaling pathway and its upstream BDNF play an important role in the enhancement of locomotor performance in mice by TI stimulation. To our knowledge, it is the first report about TI stimulation promoting multiple motor performances and describing its mechanisms. TI stimulation might serve as a novel promising approach to enhance motor performance and treat dysfunction in deep brain regions.
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Affiliation(s)
- Xiaodong Liu
- School of Exercise and Health, Shanghai University of Sport, Shanghai, China
| | - Shuo Qi
- School of Exercise and Health, Shanghai University of Sport, Shanghai, China
| | - Lijuan Hou
- College of Physical Education and Sports, Beijing Normal University, Beijing, China
| | - Yu Liu
- School of Exercise and Health, Shanghai University of Sport, Shanghai, China.
| | - Xiaohui Wang
- School of Exercise and Health, Shanghai University of Sport, Shanghai, China.
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3
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Vieira PG, Krause MR, Pack CC. Temporal interference stimulation disrupts spike timing in the primate brain. Nat Commun 2024; 15:4558. [PMID: 38811618 PMCID: PMC11137077 DOI: 10.1038/s41467-024-48962-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2023] [Accepted: 05/16/2024] [Indexed: 05/31/2024] Open
Abstract
Electrical stimulation can regulate brain activity, producing clear clinical benefits, but focal and effective neuromodulation often requires surgically implanted electrodes. Recent studies argue that temporal interference (TI) stimulation may provide similar outcomes non-invasively. During TI, scalp electrodes generate multiple electrical fields in the brain, modulating neural activity only at their intersection. Despite considerable enthusiasm for this approach, little empirical evidence demonstrates its effectiveness, especially under conditions suitable for human use. Here, using single-neuron recordings in non-human primates, we establish that TI reliably alters the timing, but not the rate, of spiking activity. However, we show that TI requires strategies-high carrier frequencies, multiple electrodes, and amplitude-modulated waveforms-that also limit its effectiveness. Combined, these factors make TI 80 % weaker than other forms of non-invasive brain stimulation. Although unlikely to cause widespread neuronal entrainment, TI may be ideal for disrupting pathological oscillatory activity, a hallmark of many neurological disorders.
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Affiliation(s)
- Pedro G Vieira
- Montreal Neurological Institute, McGill University, Montreal, Quebec, Canada
| | - Matthew R Krause
- Montreal Neurological Institute, McGill University, Montreal, Quebec, Canada.
| | - Christopher C Pack
- Montreal Neurological Institute, McGill University, Montreal, Quebec, Canada
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Vassiliadis P, Beanato E, Popa T, Windel F, Morishita T, Neufeld E, Duque J, Derosiere G, Wessel MJ, Hummel FC. Non-invasive stimulation of the human striatum disrupts reinforcement learning of motor skills. Nat Hum Behav 2024:10.1038/s41562-024-01901-z. [PMID: 38811696 DOI: 10.1038/s41562-024-01901-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2022] [Accepted: 04/23/2024] [Indexed: 05/31/2024]
Abstract
Reinforcement feedback can improve motor learning, but the underlying brain mechanisms remain underexplored. In particular, the causal contribution of specific patterns of oscillatory activity within the human striatum is unknown. To address this question, we exploited a recently developed non-invasive deep brain stimulation technique called transcranial temporal interference stimulation (tTIS) during reinforcement motor learning with concurrent neuroimaging, in a randomized, sham-controlled, double-blind study. Striatal tTIS applied at 80 Hz, but not at 20 Hz, abolished the benefits of reinforcement on motor learning. This effect was related to a selective modulation of neural activity within the striatum. Moreover, 80 Hz, but not 20 Hz, tTIS increased the neuromodulatory influence of the striatum on frontal areas involved in reinforcement motor learning. These results show that tTIS can non-invasively and selectively modulate a striatal mechanism involved in reinforcement learning, expanding our tools for the study of causal relationships between deep brain structures and human behaviour.
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Affiliation(s)
- Pierre Vassiliadis
- Defitech Chair of Clinical Neuroengineering, Neuro-X Institute, École Polytechnique Fédérale de Lausanne (EPFL), Geneva, Switzerland
- Defitech Chair of Clinical Neuroengineering, Neuro-X Institute, EPFL Valais, Clinique Romande de Réadaptation, Sion, Switzerland
- Institute of Neuroscience, Université Catholique de Louvain, Brussels, Belgium
| | - Elena Beanato
- Defitech Chair of Clinical Neuroengineering, Neuro-X Institute, École Polytechnique Fédérale de Lausanne (EPFL), Geneva, Switzerland
- Defitech Chair of Clinical Neuroengineering, Neuro-X Institute, EPFL Valais, Clinique Romande de Réadaptation, Sion, Switzerland
| | - Traian Popa
- Defitech Chair of Clinical Neuroengineering, Neuro-X Institute, École Polytechnique Fédérale de Lausanne (EPFL), Geneva, Switzerland
- Defitech Chair of Clinical Neuroengineering, Neuro-X Institute, EPFL Valais, Clinique Romande de Réadaptation, Sion, Switzerland
| | - Fabienne Windel
- Defitech Chair of Clinical Neuroengineering, Neuro-X Institute, École Polytechnique Fédérale de Lausanne (EPFL), Geneva, Switzerland
- Defitech Chair of Clinical Neuroengineering, Neuro-X Institute, EPFL Valais, Clinique Romande de Réadaptation, Sion, Switzerland
| | - Takuya Morishita
- Defitech Chair of Clinical Neuroengineering, Neuro-X Institute, École Polytechnique Fédérale de Lausanne (EPFL), Geneva, Switzerland
- Defitech Chair of Clinical Neuroengineering, Neuro-X Institute, EPFL Valais, Clinique Romande de Réadaptation, Sion, Switzerland
| | - Esra Neufeld
- Foundation for Research on Information Technologies in Society, Zurich, Switzerland
| | - Julie Duque
- Institute of Neuroscience, Université Catholique de Louvain, Brussels, Belgium
| | - Gerard Derosiere
- Institute of Neuroscience, Université Catholique de Louvain, Brussels, Belgium
- Lyon Neuroscience Research Center, Impact Team, Inserm U1028, CNRS UMR5292, Lyon 1 University, Bron, France
| | - Maximilian J Wessel
- Defitech Chair of Clinical Neuroengineering, Neuro-X Institute, École Polytechnique Fédérale de Lausanne (EPFL), Geneva, Switzerland
- Defitech Chair of Clinical Neuroengineering, Neuro-X Institute, EPFL Valais, Clinique Romande de Réadaptation, Sion, Switzerland
- Department of Neurology, University Hospital Würzburg, Würzburg, Germany
| | - Friedhelm C Hummel
- Defitech Chair of Clinical Neuroengineering, Neuro-X Institute, École Polytechnique Fédérale de Lausanne (EPFL), Geneva, Switzerland.
- Defitech Chair of Clinical Neuroengineering, Neuro-X Institute, EPFL Valais, Clinique Romande de Réadaptation, Sion, Switzerland.
- Clinical Neuroscience, University of Geneva Medical School, Geneva, Switzerland.
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Borgheai SB, Opri E, Isbaine F, Cole E, Deligani RJ, Laxpati N, Risk BB, Willie JT, Gross RE, Yong NA, McIntyre CC, Miocinovic S. Neural pathway activation in the subthalamic region depends on stimulation polarity. MEDRXIV : THE PREPRINT SERVER FOR HEALTH SCIENCES 2024:2024.05.01.24306044. [PMID: 38746250 PMCID: PMC11092741 DOI: 10.1101/2024.05.01.24306044] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2024]
Abstract
Deep brain stimulation (DBS) is an effective treatment for Parkinson's disease (PD); however, there is limited understanding of which subthalamic pathways are recruited in response to stimulation. Here, by focusing on the polarity of the stimulus waveform (cathodic vs. anodic), our goal was to elucidate biophysical mechanisms that underlie electrical stimulation in the human brain. In clinical studies, cathodic stimulation more easily triggers behavioral responses, but anodic DBS broadens the therapeutic window. This suggests that neural pathways involved respond preferentially depending on stimulus polarity. To experimentally compare the activation of therapeutically relevant pathways during cathodic and anodic subthalamic nucleus (STN) DBS, pathway activation was quantified by measuring evoked potentials resulting from antidromic or orthodromic activation in 15 PD patients undergoing DBS implantation. Cortical evoked potentials (cEP) were recorded using subdural electrocorticography, DBS local evoked potentials (DLEP) were recorded from non-stimulating contacts and EMG activity was recorded from arm and face muscles. We measured: 1) the amplitude of short-latency cEP, previously demonstrated to reflect activation of the cortico-STN hyperdirect pathway, 2) DLEP amplitude thought to reflect activation of STN-globus pallidus (GP) pathway, and 3) amplitudes of very short-latency cEP and motor evoked potentials (mEP) for activation of cortico-spinal/bulbar tract (CSBT). We constructed recruitment and strength-duration curves for each EP/pathway to compare the excitability for different stimulation polarities. We compared experimental data with the most advanced DBS computational models. Our results provide experimental evidence that subcortical cathodic and anodic stimulation activate the same pathways in the STN region and that cathodic stimulation is in general more efficient. However, relative efficiency varies for different pathways so that anodic stimulation is the least efficient in activating CSBT, more efficient in activating the HDP and as efficient as cathodic in activating STN-GP pathway. Our experiments confirm biophysical model predictions regarding neural activations in the central nervous system and provide evidence that stimulus polarity has differential effects on passing axons, terminal synapses, and local neurons. Comparison of experimental results with clinical DBS studies provides further evidence that the hyperdirect pathway may be involved in the therapeutic mechanisms of DBS.
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Liu R, Zhu G, Wu Z, Gan Y, Zhang J, Liu J, Wang L. Temporal interference stimulation targets deep primate brain. Neuroimage 2024; 291:120581. [PMID: 38508293 DOI: 10.1016/j.neuroimage.2024.120581] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2024] [Revised: 03/10/2024] [Accepted: 03/17/2024] [Indexed: 03/22/2024] Open
Abstract
Temporal interference (TI) stimulation, a novel non-invasive stimulation strategy, has recently been shown to modulate neural activity in deep brain regions of living mice. Yet, it is uncertain if this method is applicable to larger brains and whether the electric field produced under traditional safety currents can penetrate deep regions as observed in mice. Despite recent model-based simulation studies offering positive evidence at both macro- and micro-scale levels, the absence of electrophysiological data from actual brains hinders comprehensive understanding and potential application of TI. This study aims to directly measure the spatiotemporal properties of the interfered electric field in the rhesus monkey brain and to validate the effects of TI on the human brain. Two monkeys were involved in the measurement, with implantation of several stereo-electroencephalography (SEEG) depth electrodes. TI stimulation was applied to anesthetized monkeys using two pairs of surface electrodes at differing stimulation parameters. Model-based simulations were also conducted and subsequently compared with actual recordings. Additionally, TI stimulation was administered to patients with motor disorders to validate its effects on motor symptoms. Through the integration of computational electric field simulation with empirical measurements, it was determined that the temporally interfering electric fields in the deep central regions are capable of attaining a magnitude sufficient to induce a subthreshold modulation effect on neural signals. Additionally, an improvement in movement disorders was observed as a result of TI stimulation. This study is the first to systematically measure the TI electric field in living non-human primates, offering empirical evidence that TI holds promise as a more focal and precise method for modulating neural activities in deep regions of a large brain. This advancement paves the way for future applications of TI in treating neuropsychiatric disorders.
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Affiliation(s)
- Ruobing Liu
- CAS Key Laboratory of Mental Health, Institute of Psychology, Beijing, PR China; Department of Psychology, University of Chinese Academy of Sciences, Beijing, PR China
| | - Guanyu Zhu
- Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Beijing, PR China
| | - Zhengping Wu
- School of Innovations, Sanjiang University, Nanjing, PR China
| | - Yifei Gan
- Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Beijing, PR China
| | - Jianguo Zhang
- Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Beijing, PR China
| | - Jiali Liu
- CAS Key Laboratory of Mental Health, Institute of Psychology, Beijing, PR China; Department of Psychology, University of Chinese Academy of Sciences, Beijing, PR China
| | - Liang Wang
- CAS Key Laboratory of Mental Health, Institute of Psychology, Beijing, PR China; Department of Psychology, University of Chinese Academy of Sciences, Beijing, PR China.
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Mojiri Z, Akhavan A, Rouhani E, Zahabi SJ. Quantitative analysis of noninvasive deep temporal interference stimulation: A simulation and experimental study. Heliyon 2024; 10:e29482. [PMID: 38655334 PMCID: PMC11035070 DOI: 10.1016/j.heliyon.2024.e29482] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2023] [Revised: 04/07/2024] [Accepted: 04/08/2024] [Indexed: 04/26/2024] Open
Abstract
Background Deep brain stimulation (DBS) is a method for stimulating deep regions of the brain for the treatment of various neurological and psychiatric disorders such as depression, obsessive-compulsive disorder, addiction, and Parkinson's disease. Generally, DBS can be performed using both invasive and non-invasive approaches. Invasive DBS is associated with several problems, including intracranial bleeding, infection, and changes in the position of the electrode tip. Temporal interference (TI) stimulation is a non-invasive technique used to stimulate deep regions of the brain by applying two high-frequency sinusoidal currents with slightly different frequencies. New method This paper presents insights into the response of the spiking in the Hodgkin-Huxley (HH) neuron model of the rat somatosensory cortex by changing the parameters carrier frequency, current ratio, and difference frequency of TI stimulation. Furthermore, in order to experimentally evaluate the effect of TI stimulation on the activation of the left motor cortex, an experiment was conducted to measure the motion induced by the balanced and unbalanced TI stimulation. In the experiment, a three-axis accelerometer was attached to the right hand of the animal to determine the position of the hand. Results Simulation results of the HH model showed that the frequency of the envelope of the TI stimulation is identical to the fundamental frequency of the neuron spikes. This result was obtained for difference frequencies of 6 Hz and 9 Hz in balanced and unbalanced TI stimulations. Moreover specifically, when the difference frequency is set to zero, the carrier frequency is within the range of 1300-1400 Hz, and the current range is between 140 and 250 μA/cm2, the firing rate reached to its highest value. In the experimental result, the maximum range of movement at a difference frequency of Δf = 6 Hz was approximately 1.6 mm and 5.3 mm in the z and y directions respectively. Comparison with existing method The results of the spatial spectrum of the rat hand movement were consistent with the spectrum information of the simulation results. Additionally, steering the interfering region to the left motor cortex leads to noticeable contralateral movement of the right hand while no movement was observed in the right hand during the stimulation of the right motor cortex. Conclusion This technique of stimulation for the deep regions of the brain is a promising tool to noninvasively treat various neurological and psychiatric disorders such as morphine dependence in addicted rats.
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Affiliation(s)
- Zohre Mojiri
- Department of Electrical and Computer Engineering, Isfahan University of Technology, Isfahan, 84156-83111, Iran
| | - Amir Akhavan
- Department of Electrical and Computer Engineering, Isfahan University of Technology, Isfahan, 84156-83111, Iran
| | - Ehsan Rouhani
- Department of Electrical and Computer Engineering, Isfahan University of Technology, Isfahan, 84156-83111, Iran
| | - Sayed Jalal Zahabi
- Department of Electrical and Computer Engineering, Isfahan University of Technology, Isfahan, 84156-83111, Iran
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Yatsuda K, Yu W, Gomez-Tames J. Population-level insights into temporal interference for focused deep brain neuromodulation. Front Hum Neurosci 2024; 18:1308549. [PMID: 38708141 PMCID: PMC11066208 DOI: 10.3389/fnhum.2024.1308549] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2023] [Accepted: 04/09/2024] [Indexed: 05/07/2024] Open
Abstract
The ability to stimulate deep brain regions in a focal manner brings new opportunities for treating brain disorders. Temporal interference (TI) stimulation has been suggested as a method to achieve focused stimulation in deep brain targets. Individual-level knowledge of the interferential currents has permitted personalizing TI montage via subject-specific digital human head models, facilitating the estimation of interferential electric currents in the brain. While this individual approach offers a high degree of personalization, the significant intra-and inter-individual variability among specific head models poses challenges when comparing electric-field doses. Furthermore, MRI acquisition to develop a personalized head model, followed by precise methods for placing the optimized electrode positions, is complex and not always available in various clinical settings. Instead, the registration of individual electric fields into brain templates has offered insights into population-level effects and enabled montage optimization using common scalp landmarks. However, population-level knowledge of the interferential currents remains scarce. This work aimed to investigate the effectiveness of targeting deep brain areas using TI in different populations. The results showed a trade-off between deep stimulation and unwanted cortical neuromodulation, which is target-dependent at the group level. A consistent modulated electric field appeared in the deep brain target when the same montage was applied in different populations. However, the performance in terms of focality and variability varied when the same montage was used among populations. Also, group-level TI exhibited greater focality than tACS, reducing unwanted neuromodulation volume in the cortical part by at least 1.5 times, albeit with higher variability. These results provide valuable population-level insights when considering TI montage selection.
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Affiliation(s)
- Kanata Yatsuda
- Department of Medical Engineering, Graduate School of Engineering, Chiba University, Chiba, Japan
| | - Wenwei Yu
- Center for Frontier Medical Engineering, Chiba University, Chiba, Japan
| | - Jose Gomez-Tames
- Center for Frontier Medical Engineering, Chiba University, Chiba, Japan
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Zheng S, Fu T, Yan J, Zhu C, Li L, Qian Z, Lü J, Liu Y. Repetitive temporal interference stimulation improves jump performance but not the postural stability in young healthy males: a randomized controlled trial. J Neuroeng Rehabil 2024; 21:38. [PMID: 38509563 PMCID: PMC10953232 DOI: 10.1186/s12984-024-01336-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2023] [Accepted: 03/07/2024] [Indexed: 03/22/2024] Open
Abstract
BACKGROUND Temporal interference (TI) stimulation, an innovative non-invasive brain stimulation technique, has the potential to activate neurons in deep brain regions. The objective of this study was to evaluate the effects of repetitive TI stimulation targeting the lower limb motor control area (i.e., the M1 leg area) on lower limb motor function in healthy individuals, which could provide evidence for further translational application of non-invasive deep brain stimulation. METHODS In this randomized, double-blinded, parallel-controlled trial, 46 healthy male adults were randomly divided into the TI or sham group. The TI group received 2 mA (peak-to-peak) TI stimulation targeting the M1 leg area with a 20 Hz frequency difference (2 kHz and 2.02 kHz). Stimulation parameters of the sham group were consistent with those of the TI group but the current input lasted only 1 min (30 s ramp-up and ramp-down). Both groups received stimulation twice daily for five consecutive days. The vertical jump test (countermovement jump [CMJ], squat jump [SJ], and continuous jump [CJ]) and Y-balance test were performed before and after the total intervention session. Two-way repeated measures ANOVA (group × time) was performed to evaluate the effects of TI stimulation on lower limb motor function. RESULTS Forty participants completed all scheduled study visits. Two-way repeated measures ANOVA showed significant group × time interaction effects for CMJ height (F = 8.858, p = 0.005) and SJ height (F = 6.523, p = 0.015). The interaction effect of the average CJ height of the first 15 s was marginally significant (F = 3.550, p = 0.067). However, there was no significant interaction effect on the Y balance (p > 0.05). Further within-group comparisons showed a significant post-intervention increase in the height of the CMJ (p = 0.004), SJ (p = 0.010) and the average CJ height of the first 15 s (p = 0.004) in the TI group. CONCLUSION Repetitive TI stimulation targeting the lower limb motor control area effectively increased vertical jump height in healthy adult males but had no significant effect on dynamic postural stability.
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Affiliation(s)
- Suwang Zheng
- Key Laboratory of Exercise and Health Sciences of Ministry of Education, Shanghai University of Sport, Shanghai, 200438, China
- School of Exercise and Health, Shanghai University of Sport, Shanghai, 200438, China
| | - Tianli Fu
- Key Laboratory of Exercise and Health Sciences of Ministry of Education, Shanghai University of Sport, Shanghai, 200438, China
- School of Exercise and Health, Shanghai University of Sport, Shanghai, 200438, China
| | - Jinlong Yan
- Key Laboratory of Exercise and Health Sciences of Ministry of Education, Shanghai University of Sport, Shanghai, 200438, China
- School of Exercise and Health, Shanghai University of Sport, Shanghai, 200438, China
| | - Chunyue Zhu
- Key Laboratory of Exercise and Health Sciences of Ministry of Education, Shanghai University of Sport, Shanghai, 200438, China
- School of Exercise and Health, Shanghai University of Sport, Shanghai, 200438, China
| | - Lu Li
- Key Laboratory of Exercise and Health Sciences of Ministry of Education, Shanghai University of Sport, Shanghai, 200438, China
- School of Exercise and Health, Shanghai University of Sport, Shanghai, 200438, China
| | - Zhenyu Qian
- Key Laboratory of Exercise and Health Sciences of Ministry of Education, Shanghai University of Sport, Shanghai, 200438, China
- School of Exercise and Health, Shanghai University of Sport, Shanghai, 200438, China
| | - Jiaojiao Lü
- Key Laboratory of Exercise and Health Sciences of Ministry of Education, Shanghai University of Sport, Shanghai, 200438, China.
- School of Exercise and Health, Shanghai University of Sport, Shanghai, 200438, China.
| | - Yu Liu
- Key Laboratory of Exercise and Health Sciences of Ministry of Education, Shanghai University of Sport, Shanghai, 200438, China
- School of Exercise and Health, Shanghai University of Sport, Shanghai, 200438, China
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Vassiliadis P, Stiennon E, Windel F, Wessel MJ, Beanato E, Hummel FC. Safety, tolerability and blinding efficiency of non-invasive deep transcranial temporal interference stimulation: first experience from more than 250 sessions. J Neural Eng 2024; 21:024001. [PMID: 38408385 DOI: 10.1088/1741-2552/ad2d32] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2023] [Accepted: 02/26/2024] [Indexed: 02/28/2024]
Abstract
Objective. Selective neuromodulation of deep brain regions has for a long time only been possible through invasive approaches, because of the steep depth-focality trade-off of conventional non-invasive brain stimulation (NIBS) techniques.Approach. An approach that has recently emerged for deep NIBS in humans is transcranial Temporal Interference Stimulation (tTIS). However, a crucial aspect for its potential wide use is to ensure that it is tolerable, compatible with efficient blinding and safe.Main results. Here, we show the favorable tolerability and safety profiles and the robust blinding efficiency of deep tTIS targeting the striatum or hippocampus by leveraging a large dataset (119 participants, 257 sessions), including young and older adults and patients with traumatic brain injury. tTIS-evoked sensations were generally rated as 'mild', were equivalent in active and placebo tTIS conditions and did not enable participants to discern stimulation type.Significance. Overall, tTIS emerges as a promising tool for deep NIBS for robust double-blind, placebo-controlled designs.
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Affiliation(s)
- Pierre Vassiliadis
- Defitech Chair of Clinical Neuroengineering, Neuro-X Institute (INX), École Polytechnique Fédérale de Lausanne (EPFL), 1202 Geneva, Switzerland
- Defitech Chair of Clinical Neuroengineering, INX, EPFL Valais, Clinique Romande de Réadaptation, 1951 Sion, Switzerland
| | - Emma Stiennon
- Louvain School of Engineering, Université Catholique de Louvain, Louvain-la-Neuve, Belgium
| | - Fabienne Windel
- Defitech Chair of Clinical Neuroengineering, Neuro-X Institute (INX), École Polytechnique Fédérale de Lausanne (EPFL), 1202 Geneva, Switzerland
- Defitech Chair of Clinical Neuroengineering, INX, EPFL Valais, Clinique Romande de Réadaptation, 1951 Sion, Switzerland
| | | | - Elena Beanato
- Defitech Chair of Clinical Neuroengineering, Neuro-X Institute (INX), École Polytechnique Fédérale de Lausanne (EPFL), 1202 Geneva, Switzerland
- Defitech Chair of Clinical Neuroengineering, INX, EPFL Valais, Clinique Romande de Réadaptation, 1951 Sion, Switzerland
| | - Friedhelm C Hummel
- Defitech Chair of Clinical Neuroengineering, Neuro-X Institute (INX), École Polytechnique Fédérale de Lausanne (EPFL), 1202 Geneva, Switzerland
- Defitech Chair of Clinical Neuroengineering, INX, EPFL Valais, Clinique Romande de Réadaptation, 1951 Sion, Switzerland
- Clinical Neuroscience, University of Geneva Medical School, 1202 Geneva, Switzerland
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11
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Qi S, Liu X, Yu J, Liang Z, Liu Y, Wang X. Temporally interfering electric fields brain stimulation in primary motor cortex of mice promotes motor skill through enhancing neuroplasticity. Brain Stimul 2024; 17:245-257. [PMID: 38428583 DOI: 10.1016/j.brs.2024.02.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2023] [Revised: 02/09/2024] [Accepted: 02/21/2024] [Indexed: 03/03/2024] Open
Abstract
Temporal interference (TI) electric field brain stimulation is a novel neuromodulation technique that enables the non-invasive modulation of deep brain regions, but few advances about TI stimulation effectiveness and mechanisms have been reported. Conventional transcranial alternating current stimulation (tACS) can enhance motor skills, whether TI stimulation has an effect on motor skills in mice has not been elucidated. In the present study, TI stimulation was proved to stimulating noninvasively primary motor cortex (M1) of mice, and that TI stimulation with an envelope wave frequency of 20 Hz (Δ f = 20 Hz) once a day for 20 min for 7 consecutive days significantly improved the motor skills of mice. The mechanism of action may be related to regulating of neurotransmitter metabolism, increasing the expression of synapse-related proteins, promoting neurotransmitter release, increasing dendritic spine density, enhancing the number of synaptic vesicles and the thickness of postsynaptic dense material, and ultimately enhance neuronal excitability and plasticity. It is the first report about TI stimulation promoting motor skills of mice and describing its mechanisms.
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Affiliation(s)
- Shuo Qi
- Key Laboratory of Exercise and Health Sciences of Ministry of Education, Shanghai University of Sport, Shanghai, China; School of Exercise and Health, Shanghai University of Sport, Shanghai, China; School of Sport and Health, Shandong Sport University, Jinan, China
| | - Xiaodong Liu
- Key Laboratory of Exercise and Health Sciences of Ministry of Education, Shanghai University of Sport, Shanghai, China; School of Exercise and Health, Shanghai University of Sport, Shanghai, China
| | - Jinglun Yu
- Key Laboratory of Exercise and Health Sciences of Ministry of Education, Shanghai University of Sport, Shanghai, China; School of Exercise and Health, Shanghai University of Sport, Shanghai, China
| | - Zhiqiang Liang
- Key Laboratory of Exercise and Health Sciences of Ministry of Education, Shanghai University of Sport, Shanghai, China; School of Exercise and Health, Shanghai University of Sport, Shanghai, China
| | - Yu Liu
- Key Laboratory of Exercise and Health Sciences of Ministry of Education, Shanghai University of Sport, Shanghai, China; School of Exercise and Health, Shanghai University of Sport, Shanghai, China.
| | - Xiaohui Wang
- Key Laboratory of Exercise and Health Sciences of Ministry of Education, Shanghai University of Sport, Shanghai, China; School of Exercise and Health, Shanghai University of Sport, Shanghai, China.
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12
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Huang X, Wei X, Wang J, Yi G. Frequency-dependent membrane polarization across neocortical cell types and subcellular elements by transcranial alternating current stimulation. J Neural Eng 2024; 21:016034. [PMID: 38382101 DOI: 10.1088/1741-2552/ad2b8a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2023] [Accepted: 02/21/2024] [Indexed: 02/23/2024]
Abstract
Objective.Transcranial alternating current stimulation (tACS) is a non-invasive brain stimulation technique that directly interacts with ongoing brain oscillations in a frequency-dependent manner. However, it remains largely unclear how the cellular effects of tACS vary between cell types and subcellular elements.Approach.In this study, we use a set of morphologically realistic models of neocortical neurons to simulate the cellular response to uniform oscillating electric fields (EFs). We systematically characterize the membrane polarization in the soma, axons, and dendrites with varying field directions, intensities, and frequencies.Main results.Pyramidal cells are more sensitive to axial EF that is roughly parallel to the cortical column, while interneurons are sensitive to axial EF and transverse EF that is tangent to the cortical surface. Membrane polarization in each subcellular element increases linearly with EF intensity, and its slope, i.e. polarization length, highly depends on the stimulation frequency. At each frequency, pyramidal cells are more polarized than interneurons. Axons usually experience the highest polarization, followed by the dendrites and soma. Moreover, a visible frequency resonance presents in the apical dendrites of pyramidal cells, while the other subcellular elements primarily exhibit low-pass filtering properties. In contrast, each subcellular element of interneurons exhibits complex frequency-dependent polarization. Polarization phase in each subcellular element of cortical neurons lags that of field and exhibits high-pass filtering properties. These results demonstrate that the membrane polarization is not only frequency-dependent, but also cell type- and subcellular element-specific. Through relating effective length and ion mechanism with polarization, we emphasize the crucial role of cell morphology and biophysics in determining the frequency-dependent membrane polarization.Significance.Our findings highlight the diverse polarization patterns across cell types as well as subcellular elements, which provide some insights into the tACS cellular effects and should be considered when understanding the neural spiking activity by tACS.
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Affiliation(s)
- Xuelin Huang
- School of Electrical and Information Engineering, Tianjin University, Tianjin 300072, People's Republic of China
| | - Xile Wei
- School of Electrical and Information Engineering, Tianjin University, Tianjin 300072, People's Republic of China
| | - Jiang Wang
- School of Electrical and Information Engineering, Tianjin University, Tianjin 300072, People's Republic of China
| | - Guosheng Yi
- School of Electrical and Information Engineering, Tianjin University, Tianjin 300072, People's Republic of China
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13
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Sagalajev B, Zhang T, Abdollahi N, Yousefpour N, Medlock L, Al-Basha D, Ribeiro-da-Silva A, Esteller R, Ratté S, Prescott SA. Absence of paresthesia during high-rate spinal cord stimulation reveals importance of synchrony for sensations evoked by electrical stimulation. Neuron 2024; 112:404-420.e6. [PMID: 37972595 DOI: 10.1016/j.neuron.2023.10.021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2023] [Revised: 08/24/2023] [Accepted: 10/18/2023] [Indexed: 11/19/2023]
Abstract
Electrically activating mechanoreceptive afferents inhibits pain. However, paresthesia evoked by spinal cord stimulation (SCS) at 40-60 Hz becomes uncomfortable at high pulse amplitudes, limiting SCS "dosage." Kilohertz-frequency SCS produces analgesia without paresthesia and is thought, therefore, not to activate afferent axons. We show that paresthesia is absent not because axons do not spike but because they spike asynchronously. In a pain patient, selectively increasing SCS frequency abolished paresthesia and epidurally recorded evoked compound action potentials (ECAPs). Dependence of ECAP amplitude on SCS frequency was reproduced in pigs, rats, and computer simulations and is explained by overdrive desynchronization: spikes desychronize when axons are stimulated faster than their refractory period. Unlike synchronous spikes, asynchronous spikes fail to produce paresthesia because their transmission to somatosensory cortex is blocked by feedforward inhibition. Our results demonstrate how stimulation frequency impacts synchrony based on axon properties and how synchrony impacts sensation based on circuit properties.
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Affiliation(s)
- Boriss Sagalajev
- Neurosciences and Mental Health, The Hospital for Sick Children, Toronto, ON M5G 0A4, Canada
| | - Tianhe Zhang
- Boston Scientific Neuromodulation, Valencia, CA 25155, USA
| | - Nooshin Abdollahi
- Neurosciences and Mental Health, The Hospital for Sick Children, Toronto, ON M5G 0A4, Canada; Institute of Biomedical Engineering, University of Toronto, Toronto, ON M5S 3G9, Canada
| | - Noosha Yousefpour
- Department of Pharmacology and Therapeutics, McGill University, Montreal, QC H3G 1Y6, Canada
| | - Laura Medlock
- Neurosciences and Mental Health, The Hospital for Sick Children, Toronto, ON M5G 0A4, Canada; Institute of Biomedical Engineering, University of Toronto, Toronto, ON M5S 3G9, Canada
| | - Dhekra Al-Basha
- Neurosciences and Mental Health, The Hospital for Sick Children, Toronto, ON M5G 0A4, Canada; Department of Physiology, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Alfredo Ribeiro-da-Silva
- Department of Pharmacology and Therapeutics, McGill University, Montreal, QC H3G 1Y6, Canada; Department of Anatomy and Cell Biology, McGill University, Montreal, QC H3A 0C7, Canada
| | | | - Stéphanie Ratté
- Neurosciences and Mental Health, The Hospital for Sick Children, Toronto, ON M5G 0A4, Canada
| | - Steven A Prescott
- Neurosciences and Mental Health, The Hospital for Sick Children, Toronto, ON M5G 0A4, Canada; Institute of Biomedical Engineering, University of Toronto, Toronto, ON M5S 3G9, Canada; Department of Physiology, University of Toronto, Toronto, ON M5S 1A8, Canada.
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14
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Narayanan RP, Khaleghi A, Veletić M, Balasingham I. Multiphysics simulation of magnetoelectric micro core-shells for wireless cellular stimulation therapy via magnetic temporal interference. PLoS One 2024; 19:e0297114. [PMID: 38271467 PMCID: PMC10834063 DOI: 10.1371/journal.pone.0297114] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2023] [Accepted: 12/28/2023] [Indexed: 01/27/2024] Open
Abstract
This paper presents an innovative approach to wireless cellular stimulation therapy through the design of a magnetoelectric (ME) microdevice. Traditional electrophysiological stimulation techniques for neural and deep brain stimulation face limitations due to their reliance on electronics, electrode arrays, or the complexity of magnetic induction. In contrast, the proposed ME microdevice offers a self-contained, controllable, battery-free, and electronics-free alternative, holding promise for targeted precise stimulation of biological cells and tissues. The designed microdevice integrates core shell ME materials with remote coils which applies magnetic temporal interference (MTI) signals, leading to the generation of a bipolar local electric stimulation current operating at low frequencies which is suitable for precise stimulation. The nonlinear property of the magnetostrictive core enables the demodulation of remotely applied high-frequency electromagnetic fields, resulting in a localized, tunable, and manipulatable electric potential on the piezoelectric shell surface. This potential, triggers electrical spikes in neural cells, facilitating stimulation. Rigorous computational simulations support this concept, highlighting a significantly high ME coupling factor generation of 550 V/m·Oe. The high ME coupling is primarily attributed to the operation of the device in its mechanical resonance modes. This achievement is the result of a carefully designed core shell structure operating at the MTI resonance frequencies, coupled with an optimal magnetic bias, and predetermined piezo shell thickness. These findings underscore the potential of the engineered ME core shell as a candidate for wireless and minimally invasive cellular stimulation therapy, characterized by high resolution and precision. These results open new avenues for injectable material structures capable of delivering effective cellular stimulation therapy, carrying implications across neuroscience medical devices, and regenerative medicine.
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Affiliation(s)
- Ram Prasadh Narayanan
- Institute of Electronic Systems, Norwegian University of Science and Technology, Trondheim, Norway
| | - Ali Khaleghi
- Institute of Electronic Systems, Norwegian University of Science and Technology, Trondheim, Norway
- Intervention Center, Oslo University Hospital, Oslo, Norway
| | - Mladen Veletić
- Institute of Electronic Systems, Norwegian University of Science and Technology, Trondheim, Norway
- Intervention Center, Oslo University Hospital, Oslo, Norway
| | - Ilangko Balasingham
- Institute of Electronic Systems, Norwegian University of Science and Technology, Trondheim, Norway
- Intervention Center, Oslo University Hospital, Oslo, Norway
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15
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Pedersen NP, Astorga RC. Interfering with sleep apnea. Bioelectron Med 2024; 10:5. [PMID: 38263264 PMCID: PMC10807225 DOI: 10.1186/s42234-023-00139-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2023] [Accepted: 12/05/2023] [Indexed: 01/25/2024] Open
Abstract
The effects of electromagnetic interference have been hiding in plain sight for millennia and are now being applied to the non-invasive stimulation of deep tissues. In the article by Missey et al., the effect of non-invasive stimulation of the hypoglossal nerve by an interference envelope of interfering carrier waves is examined in mice and participants with sleep apnea. This stimulation is capable of activating the nerve and reducing apnea-hypopnea events. Temporally interfering electric fields have potential applications far beyond hypoglossal stimulation and may represent a revolutionary new approach to treating illness and understanding the functional organization of the nervous system.
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Affiliation(s)
- Nigel Paul Pedersen
- Department of Neurology, School of Medicine and Center for Neuroscience, University of California, Davis, 1515 Newton Court, Davis, CA, 95618, USA.
| | - Raul Castillo Astorga
- Graduate Program in Biomedical Engineering, University of California, Davis, CA, 95618, USA
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16
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Fani N, Treadway MT. Potential applications of temporal interference deep brain stimulation for the treatment of transdiagnostic conditions in psychiatry. Neuropsychopharmacology 2024; 49:305-306. [PMID: 37524751 PMCID: PMC10700552 DOI: 10.1038/s41386-023-01682-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 08/02/2023]
Affiliation(s)
- Negar Fani
- Department of Psychiatry and Behavioral Sciences, Emory University School of Medicine, Atlanta, GA, USA.
| | - Michael T Treadway
- Department of Psychiatry and Behavioral Sciences, Emory University School of Medicine, Atlanta, GA, USA
- Department of Psychology, Emory University, Atlanta, GA, USA
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17
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Luff CE, Dzialecka P, Acerbo E, Williamson A, Grossman N. Pulse-width modulated temporal interference (PWM-TI) brain stimulation. Brain Stimul 2024; 17:92-103. [PMID: 38145754 DOI: 10.1016/j.brs.2023.12.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2023] [Revised: 12/18/2023] [Accepted: 12/19/2023] [Indexed: 12/27/2023] Open
Abstract
BACKGROUND Electrical stimulation involving temporal interference of two different kHz frequency sinusoidal electric fields (temporal interference (TI)) enables non-invasive deep brain stimulation, by creating an electric field that is amplitude modulated at the slow difference frequency (within the neural range), at the target brain region. OBJECTIVE Here, we investigate temporal interference neural stimulation using square, rather than sinusoidal, electric fields that create an electric field that is pulse-width, but not amplitude, modulated at the difference frequency (pulse-width modulated temporal interference, (PWM-TI)). METHODS/RESULTS We show, using ex-vivo single-cell recordings and in-vivo calcium imaging, that PWM-TI effectively stimulates neural activity at the difference frequency at a similar efficiency to traditional TI. We then demonstrate, using computational modelling, that the PWM stimulation waveform induces amplitude-modulated membrane potential depolarization due to the membrane's intrinsic low-pass filtering property. CONCLUSIONS PWM-TI can effectively drive neural activity at the difference frequency. The PWM-TI mechanism involves converting an envelope amplitude-fixed PWM field to an amplitude-modulated membrane potential via the low-pass filtering of the passive neural membrane. Unveiling the biophysics underpinning the neural response to complex electric fields may facilitate the development of new brain stimulation strategies with improved precision and efficiency.
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Affiliation(s)
- Charlotte E Luff
- Department of Brain Sciences, Imperial College London, London, United Kingdom; UK Dementia Research Institute, Imperial College London, United Kingdom
| | - Patrycja Dzialecka
- Department of Brain Sciences, Imperial College London, London, United Kingdom; UK Dementia Research Institute, Imperial College London, United Kingdom
| | - Emma Acerbo
- Institut de Neurosciences des Systèmes (INS), INSERM, UMR_1106, Aix-Marseille Université, Marseille, France; Department of Neurosurgery, Emory University, Atlanta, GA, USA
| | - Adam Williamson
- Institut de Neurosciences des Systèmes (INS), INSERM, UMR_1106, Aix-Marseille Université, Marseille, France; International Clinical Research Center (ICRC), St. Anne's University Hospital, Brno, Czech Republic
| | - Nir Grossman
- Department of Brain Sciences, Imperial College London, London, United Kingdom; UK Dementia Research Institute, Imperial College London, United Kingdom.
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18
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Rogers ER, Mirzakhalili E, Lempka SF. Model-based analysis of subthreshold mechanisms of spinal cord stimulation for pain. J Neural Eng 2023; 20:066003. [PMID: 37906966 PMCID: PMC10632558 DOI: 10.1088/1741-2552/ad0858] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2023] [Revised: 10/11/2023] [Accepted: 10/31/2023] [Indexed: 11/02/2023]
Abstract
Objective.Spinal cord stimulation (SCS) is a common treatment for chronic pain. For decades, SCS maximized overlap between stimulation-induced paresthesias and the patient's painful areas. Recently developed SCS paradigms relieve pain at sub-perceptible amplitudes, yet little is known about the neural response to these new waveforms or their analgesic mechanisms of action. Therefore, in this study, we investigated the neural response to multiple forms of paresthesia-free SCS.Approach.We used computational modeling to investigate the neurophysiological effects and the plausibility of commonly proposed mechanisms of three paresthesia-free SCS paradigms: burst, 1 kHz, and 10 kHz SCS. Specifically, in C- and Aβ-fibers, we investigated the effects of different SCS waveforms on spike timing and activation thresholds, as well as how stochastic ion channel gating affects the response of dorsal column axons. Finally, we characterized membrane polarization of superficial dorsal horn neurons.Main results.We found that none of the SCS waveforms activate nor modulate spike timing in C-fibers. Spike timing was modulated in Aβ-fibers only at suprathreshold amplitudes. Ion channel stochasticity had little effect on Aβ-fiber activation thresholds but produced heterogeneous spike timings at suprathreshold amplitudes. Finally, local cells were preferentially polarized in their axon terminals, and the magnitude of this polarization was dependent on cellular morphology and position relative to the stimulation electrodes.Significance.Overall, the mechanisms of action of subparesthetic SCS remain unclear. Our results suggest that no SCS waveforms directly activate C-fibers, and modulation of spike timing is unlikely at subthreshold amplitudes. We conclude that potential subthreshold neuromodulatory effects of SCS on local cells are likely to be presynaptic in nature, as axons are preferentially depolarized during SCS.
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Affiliation(s)
- Evan R Rogers
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, United States of America
- Biointerfaces Institute, University of Michigan, Ann Arbor, MI, United States of America
| | - Ehsan Mirzakhalili
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, United States of America
- Biointerfaces Institute, University of Michigan, Ann Arbor, MI, United States of America
| | - Scott F Lempka
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, United States of America
- Biointerfaces Institute, University of Michigan, Ann Arbor, MI, United States of America
- Department of Anesthesiology, University of Michigan, Ann Arbor, MI, United States of America
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19
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Wessel MJ, Beanato E, Popa T, Windel F, Vassiliadis P, Menoud P, Beliaeva V, Violante IR, Abderrahmane H, Dzialecka P, Park CH, Maceira-Elvira P, Morishita T, Cassara AM, Steiner M, Grossman N, Neufeld E, Hummel FC. Noninvasive theta-burst stimulation of the human striatum enhances striatal activity and motor skill learning. Nat Neurosci 2023; 26:2005-2016. [PMID: 37857774 PMCID: PMC10620076 DOI: 10.1038/s41593-023-01457-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2022] [Accepted: 09/07/2023] [Indexed: 10/21/2023]
Abstract
The stimulation of deep brain structures has thus far only been possible with invasive methods. Transcranial electrical temporal interference stimulation (tTIS) is a novel, noninvasive technology that might overcome this limitation. The initial proof-of-concept was obtained through modeling, physics experiments and rodent models. Here we show successful noninvasive neuromodulation of the striatum via tTIS in humans using computational modeling, functional magnetic resonance imaging studies and behavioral evaluations. Theta-burst patterned striatal tTIS increased activity in the striatum and associated motor network. Furthermore, striatal tTIS enhanced motor performance, especially in healthy older participants as they have lower natural learning skills than younger subjects. These findings place tTIS as an exciting new method to target deep brain structures in humans noninvasively, thus enhancing our understanding of their functional role. Moreover, our results lay the groundwork for innovative, noninvasive treatment strategies for brain disorders in which deep striatal structures play key pathophysiological roles.
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Affiliation(s)
- Maximilian J Wessel
- Defitech Chair of Clinical Neuroengineering, Neuro-X Institute and Brain Mind Institute, École Polytechnique Fédérale de Lausanne, Geneva, Switzerland
- Defitech Chair of Clinical Neuroengineering, Neuro-X Institute and Brain Mind Institute, Clinique Romande de Réadaptation, École Polytechnique Fédérale de Lausanne, Sion, Switzerland
- Department of Neurology, University Hospital Würzburg, Würzburg, Germany
| | - Elena Beanato
- Defitech Chair of Clinical Neuroengineering, Neuro-X Institute and Brain Mind Institute, École Polytechnique Fédérale de Lausanne, Geneva, Switzerland
- Defitech Chair of Clinical Neuroengineering, Neuro-X Institute and Brain Mind Institute, Clinique Romande de Réadaptation, École Polytechnique Fédérale de Lausanne, Sion, Switzerland
| | - Traian Popa
- Defitech Chair of Clinical Neuroengineering, Neuro-X Institute and Brain Mind Institute, Clinique Romande de Réadaptation, École Polytechnique Fédérale de Lausanne, Sion, Switzerland
| | - Fabienne Windel
- Defitech Chair of Clinical Neuroengineering, Neuro-X Institute and Brain Mind Institute, École Polytechnique Fédérale de Lausanne, Geneva, Switzerland
- Defitech Chair of Clinical Neuroengineering, Neuro-X Institute and Brain Mind Institute, Clinique Romande de Réadaptation, École Polytechnique Fédérale de Lausanne, Sion, Switzerland
| | - Pierre Vassiliadis
- Defitech Chair of Clinical Neuroengineering, Neuro-X Institute and Brain Mind Institute, École Polytechnique Fédérale de Lausanne, Geneva, Switzerland
- Defitech Chair of Clinical Neuroengineering, Neuro-X Institute and Brain Mind Institute, Clinique Romande de Réadaptation, École Polytechnique Fédérale de Lausanne, Sion, Switzerland
- Institute of Neuroscience, Université Catholique de Louvain, Brussels, Belgium
| | - Pauline Menoud
- Defitech Chair of Clinical Neuroengineering, Neuro-X Institute and Brain Mind Institute, Clinique Romande de Réadaptation, École Polytechnique Fédérale de Lausanne, Sion, Switzerland
| | - Valeriia Beliaeva
- Department of Health Sciences and Technology, ETH Zurich, Zurich, Switzerland
- Neuroscience Center Zurich, Zurich, Switzerland
| | - Ines R Violante
- School of Psychology, Faculty of Health and Medical Sciences, University of Surrey, Guildford, UK
| | | | - Patrycja Dzialecka
- Department of Brain Sciences, Imperial College London, London, UK
- United Kingdom Dementia Research Institute, Imperial College London, London, UK
| | - Chang-Hyun Park
- Defitech Chair of Clinical Neuroengineering, Neuro-X Institute and Brain Mind Institute, École Polytechnique Fédérale de Lausanne, Geneva, Switzerland
- Defitech Chair of Clinical Neuroengineering, Neuro-X Institute and Brain Mind Institute, Clinique Romande de Réadaptation, École Polytechnique Fédérale de Lausanne, Sion, Switzerland
| | - Pablo Maceira-Elvira
- Defitech Chair of Clinical Neuroengineering, Neuro-X Institute and Brain Mind Institute, École Polytechnique Fédérale de Lausanne, Geneva, Switzerland
- Defitech Chair of Clinical Neuroengineering, Neuro-X Institute and Brain Mind Institute, Clinique Romande de Réadaptation, École Polytechnique Fédérale de Lausanne, Sion, Switzerland
| | - Takuya Morishita
- Defitech Chair of Clinical Neuroengineering, Neuro-X Institute and Brain Mind Institute, École Polytechnique Fédérale de Lausanne, Geneva, Switzerland
- Defitech Chair of Clinical Neuroengineering, Neuro-X Institute and Brain Mind Institute, Clinique Romande de Réadaptation, École Polytechnique Fédérale de Lausanne, Sion, Switzerland
| | - Antonino M Cassara
- Foundation for Research on Information Technologies in Society, Zurich, Switzerland
| | - Melanie Steiner
- Foundation for Research on Information Technologies in Society, Zurich, Switzerland
| | - Nir Grossman
- Department of Brain Sciences, Imperial College London, London, UK
- United Kingdom Dementia Research Institute, Imperial College London, London, UK
| | - Esra Neufeld
- Foundation for Research on Information Technologies in Society, Zurich, Switzerland
| | - Friedhelm C Hummel
- Defitech Chair of Clinical Neuroengineering, Neuro-X Institute and Brain Mind Institute, École Polytechnique Fédérale de Lausanne, Geneva, Switzerland.
- Defitech Chair of Clinical Neuroengineering, Neuro-X Institute and Brain Mind Institute, Clinique Romande de Réadaptation, École Polytechnique Fédérale de Lausanne, Sion, Switzerland.
- Clinical Neuroscience, University of Geneva Medical School, Geneva, Switzerland.
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20
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Huang Y. Visualizing interferential stimulation of human brains. Front Hum Neurosci 2023; 17:1239114. [PMID: 37954939 PMCID: PMC10637574 DOI: 10.3389/fnhum.2023.1239114] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2023] [Accepted: 10/03/2023] [Indexed: 11/14/2023] Open
Abstract
Introduction Transcranial electrical stimulation (TES) is limited in focally stimulating deep-brain regions, even with optimized stimulation montages. Recently, interferential stimulation (IFS), also known as transcranial temporal interference stimulation (TI, TIS, or tTIS), has drawn much attention in the TES community as both computational and experimental studies show that IFS can reach deep-brain areas. However, the underlying electrodynamics of IFS is complicated and difficult to visualize. Existing literature only shows static visualization of the interfered electric field induced by IFS. These could result in a simplified understanding that there is always one static focal spot between the two pairs of stimulation electrodes. This static visualization can be frequently found in the IFS literature. Here, we aimed to systematically visualize the entire dynamics of IFS. Methods and results Following the previous study, the lead field was solved for the MNI-152 head, and optimal montages using either two pairs of electrodes or two arrays of electrodes were found to stimulate a deep-brain region close to the left striatum with the highest possible focality. We then visualized the two stimulating electrical currents injected with similar frequencies. We animated the instant electric field vector at the target and one exemplary off-target location both in 3D space and as a 2D Lissajous curve. We finally visualized the distribution of the interfered electric field and the amplitude modulation envelope at an axial slice going through the target location. These two quantities were visualized in two directions: radial-in and posterior-anterior. Discussion We hope that with intuitive visualization, this study can contribute as an educational resource to the community's understanding of IFS as a powerful modality for non-invasive focal deep-brain stimulation.
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Affiliation(s)
- Yu Huang
- Research and Development, Soterix Medical Inc., Woodbridge, NJ, United States
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21
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Mirzakhalili E, Rogers ER, Lempka SF. An optimization framework for targeted spinal cord stimulation. J Neural Eng 2023; 20:056026. [PMID: 37647885 PMCID: PMC10535048 DOI: 10.1088/1741-2552/acf522] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2023] [Revised: 08/14/2023] [Accepted: 08/30/2023] [Indexed: 09/01/2023]
Abstract
Objective. Spinal cord stimulation (SCS) is a common neurostimulation therapy to manage chronic pain. Technological advances have produced new neurostimulation systems with expanded capabilities in an attempt to improve the clinical outcomes associated with SCS. However, these expanded capabilities have dramatically increased the number of possible stimulation parameters and made it intractable to efficiently explore this large parameter space within the context of standard clinical programming procedures. Therefore, in this study, we developed an optimization approach to define the optimal current amplitudes or fractions across individual contacts in an SCS electrode array(s).Approach. We developed an analytic method using the Lagrange multiplier method along with smoothing approximations. To test our optimization framework, we used a hybrid computational modeling approach that consisted of a finite element method model and multi-compartment models of axons and cells within the spinal cord. Moreover, we extended our approach to multi-objective optimization to explore the trade-off between activating regions of interest (ROIs) and regions of avoidance (ROAs).Main results. For simple ROIs, our framework suggested optimized configurations that resembled simple bipolar configurations. However, when we considered multi-objective optimization, our framework suggested nontrivial stimulation configurations that could be selected from Pareto fronts to target multiple ROIs or avoid ROAs.Significance. We developed an optimization framework for targeted SCS. Our method is analytic, which allows for the fast calculation of optimal solutions. For the first time, we provided a multi-objective approach for selective SCS. Through this approach, we were able to show that novel configurations can provide neural recruitment profiles that are not possible with conventional stimulation configurations (e.g. bipolar stimulation). Most importantly, once integrated with computational models that account for sources of interpatient variability (e.g. anatomy, electrode placement), our optimization framework can be utilized to provide stimulation settings tailored to the needs of individual patients.
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Affiliation(s)
- Ehsan Mirzakhalili
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, United States of America
- Biointerfaces Institute, University of Michigan, Ann Arbor, MI, United States of America
| | - Evan R Rogers
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, United States of America
- Biointerfaces Institute, University of Michigan, Ann Arbor, MI, United States of America
| | - Scott F Lempka
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, United States of America
- Biointerfaces Institute, University of Michigan, Ann Arbor, MI, United States of America
- Department of Anesthesiology, University of Michigan, Ann Arbor, MI, United States of America
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22
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Zhu Z, Yin L. A mini-review: recent advancements in temporal interference stimulation in modulating brain function and behavior. Front Hum Neurosci 2023; 17:1266753. [PMID: 37780965 PMCID: PMC10539552 DOI: 10.3389/fnhum.2023.1266753] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2023] [Accepted: 09/04/2023] [Indexed: 10/03/2023] Open
Abstract
Numerous studies have assessed the effect of Temporal Interference (TI) on human performance. However, a comprehensive literature review has not yet been conducted. Therefore, this review aimed to search PubMed and Web of Science databases for TI-related literature and analyze the findings. We analyzed studies involving preclinical, human, and computer simulations, and then discussed the mechanism and safety of TI. Finally, we identified the gaps and outlined potential future directions. We believe that TI is a promising technology for the treatment of neurological movement disorders, due to its superior focality, steerability, and tolerability compared to traditional electrical stimulation. However, human experiments have yielded fewer and inconsistent results, thus animal and simulation experiments are still required to perfect stimulation protocols for human trials.
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Affiliation(s)
| | - Lijun Yin
- School of Sport, Shenzhen University, Shenzhen, China
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23
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Xin Z, Abe Y, Kuwahata A, Tanaka KF, Sekino M. Brain Response to Interferential Current Compared with Alternating Current Stimulation. Brain Sci 2023; 13:1317. [PMID: 37759918 PMCID: PMC10526916 DOI: 10.3390/brainsci13091317] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Revised: 09/02/2023] [Accepted: 09/11/2023] [Indexed: 09/29/2023] Open
Abstract
Temporal interference (TI) stimulation, which utilizes multiple external electric fields with amplitude modulation for neural modulation, has emerged as a potential noninvasive brain stimulation methodology. However, the clinical application of TI stimulation is inhibited by its uncertain fundamental mechanisms, and research has previously been restricted to numerical simulations and immunohistology without considering the acute in vivo response of the neural circuit. To address the characterization and understanding of the mechanisms underlying the approach, we investigated instantaneous brainwide activation patterns in response to invasive interferential current (IFC) stimulation compared with low-frequency alternative current stimulation (ACS). Results demonstrated that IFC stimulation is capable of inducing regional neural responses and modulating brain networks; however, the activation threshold for significantly recruiting a neural response using IFC was higher (at least twofold) than stimulation via alternating current, and the spatial distribution of the activation signal was restricted. A distinct blood oxygenation level-dependent (BOLD) response pattern was observed, which could be accounted for by the activation of distinct types of cells, such as inhibitory cells, by IFC. These results suggest that IFC stimulation might not be as efficient as conventional brain modulation methods, especially when considering TI stimulation as a potential alternative for stimulating subcortical brain areas. Therefore, we argue that a future transcranial application of TI on human subjects should take these implications into account and consider other stimulation effects using this technique.
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Affiliation(s)
- Zonghao Xin
- Department of Bioengineering, School of Engineering, The University of Tokyo, Tokyo 113-8656, Japan;
| | - Yoshifumi Abe
- Division of Brain Sciences, Institute for Advanced Medical Research, Keio University School of Medicine, Tokyo 160-8582, Japan; (Y.A.); (K.F.T.)
| | - Akihiro Kuwahata
- Department of Electrical Engineering, Graduate School of Engineering, Tohoku University, Sendai 980-8579, Japan;
| | - Kenji F. Tanaka
- Division of Brain Sciences, Institute for Advanced Medical Research, Keio University School of Medicine, Tokyo 160-8582, Japan; (Y.A.); (K.F.T.)
| | - Masaki Sekino
- Department of Bioengineering, School of Engineering, The University of Tokyo, Tokyo 113-8656, Japan;
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24
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Kwak Y, Lim S, Cho HU, Sim J, Lee S, Jeong S, Jeon SJ, Im CH, Jang DP. Effect of temporal interference electrical stimulation on phasic dopamine release in the striatum. Brain Stimul 2023; 16:1377-1383. [PMID: 37716638 DOI: 10.1016/j.brs.2023.09.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2023] [Revised: 09/10/2023] [Accepted: 09/13/2023] [Indexed: 09/18/2023] Open
Abstract
BACKGROUND Temporal interference stimulation (TIS) is a neuromodulation technique that could stimulate deep brain regions by inducing interfering electrical signals based on high-frequency electrical stimulations of multiple electrode pairs from outside the brain. Despite numerous TIS studies, however, there has been limited investigation into the neurochemical effects of TIS. OBJECTIVE We performed two experiments to investigate the effect of TIS on the medial forebrain bundle (MFB)-evoked phasic dopamine (DA) response. METHODS In the first experiment, we applied TIS next to a carbon fiber microelectrode (CFM) to examine the modulation of the MFB-evoked phasic DA response in the striatum (STr). Beat frequencies and intensities of TIS were 0, 2, 6, 10, 20, 60, 130 Hz and 0, 100, 200, 300, 400, 500 μA. In the second experiment, we examined the effect of TIS with a 2 Hz beat frequency (based on the first experiment) on MFB-evoked phasic DA release when applied above the cortex (with a simulation-based stimulation site targeting the striatum). We employed 0 Hz and 2 Hz beat frequencies and a control condition without stimulation. RESULTS In the first experiment, TIS with a beat frequency of 2 Hz and an intensity of 400 μA or greater decreased MFB-evoked phasic DA release by roughly 40%, which continued until the experiment's end. In contrast, TIS at beat frequencies other than 2 Hz and intensities less than 400 μA did not affect MFB-evoked phasic DA release. In the second experiment, TIS with a 2 Hz beat frequency decreased only the MFB-evoked phasic DA response, but the reduction in DA release was not sustained. CONCLUSIONS STr-applied and cortex-applied TIS with delta frequency dampens evoked phasic DA release in the STr. These findings demonstrate that TIS could influence the neurochemical modulation of the brain.
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Affiliation(s)
- Youngjong Kwak
- Department of Biomedical Engineering, Hanyang University, Seoul, Republic of Korea
| | - Seokbeen Lim
- Department of Biomedical Engineering, Hanyang University, Seoul, Republic of Korea
| | - Hyun-U Cho
- Department of Biomedical Engineering, Hanyang University, Seoul, Republic of Korea
| | - Jeongeun Sim
- Department of Biomedical Engineering, Hanyang University, Seoul, Republic of Korea
| | - Sangjun Lee
- Department of Biomedical Engineering, University of Minnesota, MN, USA
| | - Suhyeon Jeong
- School of Medicine and Center for Neuroscience Research, Konkuk University, Seoul, Republic of Korea
| | - Se Jin Jeon
- Department of Pharmacology, College of Medicine, Hallym University, Gangwon, Republic of Korea
| | - Chang-Hwan Im
- Department of Biomedical Engineering, Hanyang University, Seoul, Republic of Korea
| | - Dong Pyo Jang
- Department of Biomedical Engineering, Hanyang University, Seoul, Republic of Korea.
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25
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Makaroff SN, Nummenmaa AR, Noetscher GM, Qi Z, McIntyre CC, Bingham CS. Influence of charges deposited on membranes of human hyperdirect pathway axons on depolarization during subthalamic deep brain stimulation. J Neural Eng 2023; 20:10.1088/1741-2552/ace5de. [PMID: 37429285 PMCID: PMC10542971 DOI: 10.1088/1741-2552/ace5de] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2023] [Accepted: 07/10/2023] [Indexed: 07/12/2023]
Abstract
Objective.The motor hyperdirect pathway (HDP) is a key target in the treatment of Parkinson's disease with deep brain stimulation (DBS). Biophysical models of HDP DBS have been used to explore the mechanisms of stimulation. Built upon finite element method volume conductor solutions, such models are limited by a resolution mismatch, where the volume conductor is modeled at the macro scale, while the neural elements are at the micro scale. New techniques are needed to better integrate volume conductor models with neuron models.Approach.We simulated subthalamic DBS of the human HDP using finely meshed axon models to calculate surface charge deposition on insulting membranes of nonmyelinated axons. We converted the corresponding double layer extracellular problem to a single layer problem and applied the well-conditioned charge-based boundary element fast multipole method (BEM-FMM) with unconstrained numerical spatial resolution. Commonly used simplified estimations of membrane depolarization were compared with more realistic solutions.Main result.Neither centerline potential nor estimates of axon recruitment were impacted by the estimation method used except at axon bifurcations and hemispherical terminations. Local estimates of axon polarization were often much higher at bifurcations and terminations than at any other place along the axon and terminal arbor. Local average estimates of terminal electric field are higher by 10%-20%.Significance. Biophysical models of action potential initiation in the HDP suggest that axon terminations are often the lowest threshold elements for activation. The results of this study reinforce that hypothesis and suggest that this phenomenon is even more pronounced than previously realized.
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Affiliation(s)
- Sergey N Makaroff
- Electrical and Computer Engineering Department, Worcester Polytechnic Institution, Worcester, MA 01609, United States of America
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA 02129, United States of America
| | - Aapo R Nummenmaa
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA 02129, United States of America
| | - Gregory M Noetscher
- Electrical and Computer Engineering Department, Worcester Polytechnic Institution, Worcester, MA 01609, United States of America
- ARMY DEVCOM-SC, General Greene Ave, Natick, MA 01760, United States of America
| | - Zhen Qi
- Electrical and Computer Engineering Department, Worcester Polytechnic Institution, Worcester, MA 01609, United States of America
| | - Cameron C McIntyre
- Department of Biomedical Engineering, Duke University, Durham, NC 27708, United States of America
- Department of Neurosurgery, Duke University, Durham, NC 27710, United States of America
| | - Clayton S Bingham
- Department of Biomedical Engineering, Duke University, Durham, NC 27708, United States of America
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26
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Iszak K, Gronemann SM, Meyer S, Hunold A, Zschüntzsch J, Bähr M, Paulus W, Antal A. Why Temporal Inference Stimulation May Fail in the Human Brain: A Pilot Research Study. Biomedicines 2023; 11:1813. [PMID: 37509455 PMCID: PMC10376875 DOI: 10.3390/biomedicines11071813] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2023] [Revised: 06/13/2023] [Accepted: 06/21/2023] [Indexed: 07/30/2023] Open
Abstract
Temporal interference stimulation (TIS) aims at targeting deep brain areas during transcranial electrical alternating current stimulation (tACS) by generating interference fields at depth. Although its modulatory effects have been demonstrated in animal and human models and stimulation studies, direct experimental evidence is lacking for its utility in humans (in vivo). Herein, we directly test and compare three different structures: firstly, we perform peripheral nerve and muscle stimulation quantifying muscle twitches as readout, secondly, we stimulate peri-orbitally with phosphene perception as a surrogate marker, and thirdly, we attempt to modulate the mean power of alpha oscillations in the occipital area as measured with electroencephalography (EEG). We found strong evidence for stimulation efficacy on the modulated frequency in the PNS, but we found no evidence for its utility in the CNS. Possible reasons for failing to activate CNS targets could be comparatively higher activation thresholds here or inhibitory stimulation components to the carrier frequency interfering with the effects of the modulated signal.
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Affiliation(s)
- Krisztián Iszak
- Department of Neurology, University Medical Center Göttingen, Georg-August University, 37075 Göttingen, Germany
| | - Simon Mathies Gronemann
- Department of Neurology, University Medical Center Göttingen, Georg-August University, 37075 Göttingen, Germany
| | - Stefanie Meyer
- Department of Neurology, University Medical Center Göttingen, Georg-August University, 37075 Göttingen, Germany
| | - Alexander Hunold
- Institute of Biomedical Engineering and Informatics, Ilmenau University of Technology, 98684 Ilmenau, Germany
| | - Jana Zschüntzsch
- Department of Neurology, University Medical Center Göttingen, Georg-August University, 37075 Göttingen, Germany
| | - Mathias Bähr
- Department of Neurology, University Medical Center Göttingen, Georg-August University, 37075 Göttingen, Germany
| | - Walter Paulus
- Department of Neurology, Ludwig-Maximilians University Munich, Klinikum Großhadern, 81377 München, Germany
| | - Andrea Antal
- Department of Neurology, University Medical Center Göttingen, Georg-August University, 37075 Göttingen, Germany
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27
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Karatum O, Han M, Erdogan ET, Karamursel S, Nizamoglu S. Physical mechanisms of emerging neuromodulation modalities. J Neural Eng 2023; 20:031001. [PMID: 37224804 DOI: 10.1088/1741-2552/acd870] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2022] [Accepted: 05/24/2023] [Indexed: 05/26/2023]
Abstract
One of the ultimate goals of neurostimulation field is to design materials, devices and systems that can simultaneously achieve safe, effective and tether-free operation. For that, understanding the working mechanisms and potential applicability of neurostimulation techniques is important to develop noninvasive, enhanced, and multi-modal control of neural activity. Here, we review direct and transduction-based neurostimulation techniques by discussing their interaction mechanisms with neurons via electrical, mechanical, and thermal means. We show how each technique targets modulation of specific ion channels (e.g. voltage-gated, mechanosensitive, heat-sensitive) by exploiting fundamental wave properties (e.g. interference) or engineering nanomaterial-based systems for efficient energy transduction. Overall, our review provides a detailed mechanistic understanding of neurostimulation techniques together with their applications toin vitro, in vivo, and translational studies to guide the researchers toward developing more advanced systems in terms of noninvasiveness, spatiotemporal resolution, and clinical applicability.
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Affiliation(s)
- Onuralp Karatum
- Department of Electrical and Electronics Engineering, Koc University, Istanbul 34450, Turkey
| | - Mertcan Han
- Department of Electrical and Electronics Engineering, Koc University, Istanbul 34450, Turkey
| | - Ezgi Tuna Erdogan
- Department of Physiology, Koc University School of Medicine, Istanbul 34450, Turkey
| | - Sacit Karamursel
- Department of Physiology, Koc University School of Medicine, Istanbul 34450, Turkey
| | - Sedat Nizamoglu
- Department of Electrical and Electronics Engineering, Koc University, Istanbul 34450, Turkey
- Department of Biomedical Science and Engineering, Koc University, Istanbul 34450, Turkey
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28
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Fisher LE, Lempka SF. Neurotechnology for Pain. Annu Rev Biomed Eng 2023; 25:387-412. [PMID: 37068766 DOI: 10.1146/annurev-bioeng-111022-121637] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/19/2023]
Abstract
Neurotechnologies for treating pain rely on electrical stimulation of the central or peripheral nervous system to disrupt or block pain signaling and have been commercialized to treat a variety of pain conditions. While their adoption is accelerating, neurotechnologies are still frequently viewed as a last resort, after many other treatment options have been explored. We review the pain conditions commonly treated with electrical stimulation, as well as the specific neurotechnologies used for treating those conditions. We identify barriers to adoption, including a limited understanding of mechanisms of action, inconsistent efficacy across patients, and challenges related to selectivity of stimulation and off-target side effects. We describe design improvements that have recently been implemented, as well as some cutting-edge technologies that may address the limitations of existing neurotechnologies. Addressing these challenges will accelerate adoption and change neurotechnologies from last-line to first-line treatments for people living with chronic pain.
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Affiliation(s)
- Lee E Fisher
- Rehab Neural Engineering Labs, Department of Physical Medicine and Rehabilitation, and Department of Bioengineering, University of Pittsburgh, Pittsburgh, Pennsylvania, USA;
- Department of Biomedical Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania, USA
| | - Scott F Lempka
- Department of Biomedical Engineering, Biointerfaces Institute, and Department of Anesthesiology, University of Michigan, Ann Arbor, Michigan, USA;
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29
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Carmona-Barrón VG, Fernández del Campo IS, Delgado-García JM, De la Fuente AJ, Lopez IP, Merchán MA. Comparing the effects of transcranial alternating current and temporal interference (tTIS) electric stimulation through whole-brain mapping of c-Fos immunoreactivity. Front Neuroanat 2023; 17:1128193. [PMID: 36992795 PMCID: PMC10040600 DOI: 10.3389/fnana.2023.1128193] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2022] [Accepted: 02/16/2023] [Indexed: 03/16/2023] Open
Abstract
The analysis of the topography of brain neuromodulation following transcranial alternating current (AC) stimulation is relevant for defining strategies directed to specific nuclei stimulation in patients. Among the different procedures of AC stimulation, temporal interference (tTIS) is a novel method for non-invasive neuromodulation of specific deep brain targets. However, little information is currently available about its tissue effects and its activation topography in in vivo animal models. After a single session (30 min, 0.12 mA) of transcranial alternate current (2,000 Hz; ES/AC group) or tTIS (2,000/2,010 Hz; Es/tTIS group) stimulation, rat brains were explored by whole-brain mapping analysis of c-Fos immunostained serial sections. For this analysis, we used two mapping methods, namely density-to-color processed channels (independent component analysis (ICA) and graphical representation (MATLAB) of morphometrical and densitometrical values obtained by density threshold segmentation. In addition, to assess tissue effects, alternate serial sections were stained for glial fibrillary acidic protein (GFAP), ionized calcium-binding adapter molecule 1 (Iba1), and Nissl. AC stimulation induced a mild superficial increase in c-Fos immunoreactivity. However, tTIS stimulation globally decreased the number of c-Fos-positive neurons and increased blood brain barrier cell immunoreactivity. tTIS also had a stronger effect around the electrode placement area and preserved neuronal activation better in restricted areas of the deep brain (directional stimulation). The enhanced activation of intramural blood vessels’ cells and perivascular astrocytes suggests that low-frequency interference (10 Hz) may also have a trophic effect.
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Affiliation(s)
| | | | | | - Antonio J. De la Fuente
- Institute of Neuroscience of Castilla y Leon (INCYL), University of Salamanca, Salamanca, Spain
| | - Ignacio Plaza Lopez
- Institute of Neuroscience of Castilla y Leon (INCYL), University of Salamanca, Salamanca, Spain
| | - Miguel A. Merchán
- Institute of Neuroscience of Castilla y Leon (INCYL), University of Salamanca, Salamanca, Spain
- *Correspondence: Miguel A. Merchán
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30
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Guo W, He Y, Zhang W, Sun Y, Wang J, Liu S, Ming D. A novel non-invasive brain stimulation technique: "Temporally interfering electrical stimulation". Front Neurosci 2023; 17:1092539. [PMID: 36777641 PMCID: PMC9912300 DOI: 10.3389/fnins.2023.1092539] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Accepted: 01/17/2023] [Indexed: 01/30/2023] Open
Abstract
For decades, neuromodulation technology has demonstrated tremendous potential in the treatment of neuropsychiatric disorders. However, challenges such as being less intrusive, more concentrated, using less energy, and better public acceptance, must be considered. Several novel and optimized methods are thus urgently desiderated to overcome these barriers. In specific, temporally interfering (TI) electrical stimulation was pioneered in 2017, which used a low-frequency envelope waveform, generated by the superposition of two high-frequency sinusoidal currents of slightly different frequency, to stimulate specific targets inside the brain. TI electrical stimulation holds the advantages of both spatial targeting and non-invasive character. The ability to activate deep pathogenic targets without surgery is intriguing, and it is expected to be employed to treat some neurological or psychiatric disorders. Recently, efforts have been undertaken to investigate the stimulation qualities and translation application of TI electrical stimulation via computational modeling and animal experiments. This review detailed the most recent scientific developments in the field of TI electrical stimulation, with the goal of serving as a reference for future research.
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Affiliation(s)
- Wanting Guo
- Academy of Medical Engineering and Translational Medicine, Tianjin University, Tianjin, China
| | - Yuchen He
- Academy of Medical Engineering and Translational Medicine, Tianjin University, Tianjin, China
| | - Wenquan Zhang
- Academy of Medical Engineering and Translational Medicine, Tianjin University, Tianjin, China
| | - Yiwei Sun
- Academy of Medical Engineering and Translational Medicine, Tianjin University, Tianjin, China
| | - Junling Wang
- Academy of Medical Engineering and Translational Medicine, Tianjin University, Tianjin, China
| | - Shuang Liu
- Academy of Medical Engineering and Translational Medicine, Tianjin University, Tianjin, China,*Correspondence: Shuang Liu,
| | - Dong Ming
- Academy of Medical Engineering and Translational Medicine, Tianjin University, Tianjin, China,Department of Biomedical Engineering, College of Precision Instruments and Optoelectronics Engineering, Tianjin University, Tianjin, China,Tianjin International Joint Research Center for Neural Engineering, Tianjin, China,Dong Ming,
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31
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Khalifa A, Abrishami SM, Zaeimbashi M, Tang AD, Coughlin B, Rodger J, Sun NX, Cash SS. Magnetic temporal interference for noninvasive and focal brain stimulation. J Neural Eng 2023; 20. [PMID: 36651596 DOI: 10.1088/1741-2552/acb015] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2022] [Accepted: 01/04/2023] [Indexed: 01/19/2023]
Abstract
Objective. Noninvasive focal stimulation of deep brain regions has been a major goal for neuroscience and neuromodulation in the past three decades. Transcranial magnetic stimulation (TMS), for instance, cannot target deep regions in the brain without activating the overlying tissues and has poor spatial resolution. In this manuscript, we propose a new concept that relies on the temporal interference (TI) of two high-frequency magnetic fields generated by two electromagnetic solenoids.Approach. To illustrate the concept, custom solenoids were fabricated and optimized to generate temporal interfering electric fields for rodent brain stimulation. C-Fos expression was used to track neuronal activation.Main result. C-Fos expression was not present in regions impacted by only one high-frequency magnetic field indicating ineffective recruitment of neural activity in non-target regions. In contrast, regions impacted by two fields that interfere to create a low-frequency envelope display a strong increase in c-Fos expression.Significance. Therefore, this magnetic temporal interference solenoid-based system provides a framework to perform further stimulation studies that would investigate the advantages it could bring over conventional TMS systems.
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Affiliation(s)
- Adam Khalifa
- Department of Electrical and Computer Engineering, University of Florida, Gainesville, FL, United States of America
| | - Seyed Mahdi Abrishami
- Department of Electrical and Computer Engineering, Northeastern University, Boston, MA, United States of America
| | - Mohsen Zaeimbashi
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, United States of America
| | - Alexander D Tang
- Experimental and Regenerative Neurosciences, School of Biological Sciences, University of Western Australia, WA, Australia.,Perron Institute for Neurological and Translational, University of Western Australia, WA, Australia
| | - Brian Coughlin
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, United States of America
| | - Jennifer Rodger
- Experimental and Regenerative Neurosciences, School of Biological Sciences, University of Western Australia, WA, Australia.,Perron Institute for Neurological and Translational, University of Western Australia, WA, Australia
| | - Nian X Sun
- Department of Electrical and Computer Engineering, Northeastern University, Boston, MA, United States of America
| | - Sydney S Cash
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, United States of America
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32
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Wang B, Aberra AS, Grill WM, Peterchev AV. Responses of model cortical neurons to temporal interference stimulation and related transcranial alternating current stimulation modalities. J Neural Eng 2023; 19:10.1088/1741-2552/acab30. [PMID: 36594634 PMCID: PMC9942661 DOI: 10.1088/1741-2552/acab30] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2022] [Accepted: 12/13/2022] [Indexed: 12/15/2022]
Abstract
Objective.Temporal interference stimulation (TIS) was proposed as a non-invasive, focal, and steerable deep brain stimulation method. However, the mechanisms underlying experimentally-observed suprathreshold TIS effects are unknown, and prior simulation studies had limitations in the representations of the TIS electric field (E-field) and cerebral neurons. We examined the E-field and neural response characteristics for TIS and related transcranial alternating current stimulation modalities.Approach.Using the uniform-field approximation, we simulated a range of stimulation parameters in biophysically realistic model cortical neurons, including different orientations, frequencies, amplitude ratios, amplitude modulation, and phase difference of the E-fields, and obtained thresholds for both activation and conduction block.Main results. For two E-fields with similar amplitudes (representative of E-field distributions at the target region), TIS generated an amplitude-modulated (AM) total E-field. Due to the phase difference of the individual E-fields, the total TIS E-field vector also exhibited rotation where the orientations of the two E-fields were not aligned (generally also at the target region). TIS activation thresholds (75-230 V m-1) were similar to those of high-frequency stimulation with or without modulation and/or rotation. For E-field dominated by the high-frequency carrier and with minimal amplitude modulation and/or rotation (typically outside the target region), TIS was less effective at activation and more effective at block. Unlike AM high-frequency stimulation, TIS generated conduction block with some orientations and amplitude ratios of individual E-fields at very high amplitudes of the total E-field (>1700 V m-1).Significance. The complex 3D properties of the TIS E-fields should be accounted for in computational and experimental studies. The mechanisms of suprathreshold cortical TIS appear to involve neural activity block and periodic activation or onset response, consistent with computational studies of peripheral axons. These phenomena occur at E-field strengths too high to be delivered tolerably through scalp electrodes and may inhibit endogenous activity in off-target regions, suggesting limited significance of suprathreshold TIS.
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Affiliation(s)
- Boshuo Wang
- Department of Psychiatry and Behavioral Sciences, School of Medicine, Duke University, Durham, NC 27710, USA
| | - Aman S. Aberra
- Department of Biomedical Engineering, School of Engineering, Duke University, Durham, NC 27708, USA
| | - Warren M. Grill
- Department of Biomedical Engineering, School of Engineering, Duke University, Durham, NC 27708, USA
- Department of Electrical and Computer Engineering, School of Engineering, Duke University, Durham, NC 27708, USA
- Department of Neurobiology, School of Medicine, Duke University, Durham, NC 27710, USA
- Department of Neurosurgery, School of Medicine, Duke University, Durham, NC 27710, USA
| | - Angel V. Peterchev
- Department of Psychiatry and Behavioral Sciences, School of Medicine, Duke University, Durham, NC 27710, USA
- Department of Biomedical Engineering, School of Engineering, Duke University, Durham, NC 27708, USA
- Department of Electrical and Computer Engineering, School of Engineering, Duke University, Durham, NC 27708, USA
- Department of Neurosurgery, School of Medicine, Duke University, Durham, NC 27710, USA
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33
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Bahn S, Lee C, Kang B. A computational study on the optimization of transcranial temporal interfering stimulation with high-definition electrodes using unsupervised neural networks. Hum Brain Mapp 2022; 44:1829-1845. [PMID: 36527707 PMCID: PMC9980883 DOI: 10.1002/hbm.26181] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2022] [Revised: 11/24/2022] [Accepted: 11/28/2022] [Indexed: 12/23/2022] Open
Abstract
Transcranial temporal interfering stimulation (tTIS) can focally stimulate deep parts of the brain related to specific functions using beats at two high frequencies that do not individually affect the human brain. However, the complexity and nonlinearity of the simulation limit it in terms of calculation time and optimization precision. We propose a method to quickly optimize the interfering current value of high-definition electrodes, which can finely stimulate the deep part of the brain, using an unsupervised neural network (USNN) for tTIS. We linked a network that generates the values of electrode currents to another network, which is constructed to compute the interference exposure, for optimization by comparing the generated stimulus with the target stimulus. Further, a computational study was conducted using 16 realistic head models. We also compared tTIS with transcranial alternating current stimulation (tACS), in terms of performance and characteristics. The proposed method generated the strongest stimulation at the target, even when targeting deep areas or performing multi-target stimulation. The high-definition tTISl was less affected than tACS by target depth, and mis-stimulation was reduced compared with the case of using two-pair inferential stimulation in deep region. The optimization of the electrode currents for the target stimulus could be performed in 3 min. Using the proposed USNN for tTIS, we demonstrated that the electrode currents of tTIS can be optimized quickly and accurately. Moreover, we confirmed the possibility of precisely stimulating the deep parts of the brain via transcranial electrical stimulation.
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Affiliation(s)
- Sangkyu Bahn
- Cognitive Science Research GroupKorea Brain Research InstituteDaeguRepublic of Korea
| | - Chany Lee
- Cognitive Science Research GroupKorea Brain Research InstituteDaeguRepublic of Korea
| | - Bo‐Yeong Kang
- School of ConvergenceKyungpook National UniversityDaeguRepublic of Korea
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Cerpa E, Courdurier M, Hernández E, Medina LE, Paduro E. A partially averaged system to model neuron responses to interferential current stimulation. J Math Biol 2022; 86:8. [PMID: 36469157 DOI: 10.1007/s00285-022-01839-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2022] [Revised: 11/14/2022] [Accepted: 11/17/2022] [Indexed: 12/12/2022]
Abstract
The interferential current (IFC) therapy is a noninvasive electrical neurostimulation technique intended to activate deep neurons using surface electrodes. In IFC, two independent kilohertz-frequency currents purportedly intersect where an interference field is generated. However, the effects of IFC on neurons within and outside the interference field are not completely understood, and it is unclear whether this technique can reliable activate deep target neurons without side effects. In recent years, realistic computational models of IFC have been introduced to quantify the effects of IFC on brain cells, but they are often complex and computationally costly. Here, we introduce a simplified model of IFC based on the FitzHugh-Nagumo (FHN) model of a neuron. By considering a modified averaging method, we obtain a non-autonomous approximated system, with explicit representation of relevant IFC parameters. For this approximated system we determine conditions under which it reliably approximates the complete FHN system under IFC stimulation, and we mathematically prove its ability to predict nonspiking states. In addition, we perform numerical simulations that show that the interference effect is observed only for a narrow set of IFC parameters and, in particular, for a beat frequency no higher than about 100 [Hz]. Our novel model tailored to the IFC technique contributes to the understanding of neurostimulation modalities using this type of signals, and can have implications in the design of noninvasive electrical stimulation therapies.
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Affiliation(s)
- Eduardo Cerpa
- Facultad de Matemáticas, Instituto de Ingeniería Matemática y Computacional, Pontificia Universidad Católica de Chile, Avda. Vicuña Mackenna 4860, Macul, Santiago, 7820436, Chile.,Millennium Nucleus for Applied Control and Inverse Problems, Santiago, Chile
| | - Matías Courdurier
- Departamento de Matemática, Facultad de Matemáticas, Pontificia Universidad Católica de Chile, Avda. Vicuña Mackenna 4860, Macul, Santiago, 7820436, Chile.,Millennium Nucleus for Applied Control and Inverse Problems, Santiago, Chile
| | - Esteban Hernández
- Departamento de Matemática, Universidad Técnica Federico Santa María, Avda. España 1680, Valparaíso, 2390123, Chile
| | - Leonel E Medina
- Departamento de Ingeniería Informática, Universidad de Santiago de Chile, Avda. Víctor Jara 3659, Estación Central, Santiago, 9170124, Chile.,Millennium Nucleus for Applied Control and Inverse Problems, Santiago, Chile
| | - Esteban Paduro
- Facultad de Matemáticas, Instituto de Ingeniería Matemática y Computacional, Pontificia Universidad Católica de Chile, Avda. Vicuña Mackenna 4860, Macul, Santiago, 7820436, Chile. .,Millennium Nucleus for Applied Control and Inverse Problems, Santiago, Chile.
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35
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Zhang Y, Zhou Z, Zhou J, Qian Z, Lü J, Li L, Liu Y. Temporal interference stimulation targeting right frontoparietal areas enhances working memory in healthy individuals. Front Hum Neurosci 2022; 16:918470. [PMID: 36393981 PMCID: PMC9650295 DOI: 10.3389/fnhum.2022.918470] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2022] [Accepted: 10/06/2022] [Indexed: 11/23/2022] Open
Abstract
Background Temporal interference (TI) stimulation is a novel technique that enables the non-invasive modulation of deep brain regions. However, the implementation of this technology in humans has not been well-characterized or examined, including its safety and feasibility. Objective We aimed to examine the feasibility, safety, and blinding of using TI on human participants in this pilot study. Materials and methods In a randomized, single-blinded, and sham-controlled pilot study, healthy young participants were randomly divided into four groups [TI and transcranial alternating current stimulation (tACS) targeting the right frontoparietal region, TI-sham, and tACS-sham]. Each participant was asked to complete N-back (N = 1 to 3) tasks before, during, and after one session of stimulation to assess their working memory (WM). The side effects and blinding efficacy were carefully assessed. The accuracy, reaction time (RT), and inverse efficiency score (IES, reaction time/accuracy) of the N-back tasks were measured. Results No severe side effects were reported. Only mild-to-moderate side effects were observed in those who received TI, which was similar to those observed in participants receiving tACS. The blinding efficacy was excellent, and there was no correlation between the severity of the reported side effects and the predicted type of stimulation that the participants received. WM appeared to be only marginally improved by TI compared to tACS-sham, and this improvement was only observed under high-load cognitive tasks. WM seemed to have improved a little in the TI-sham group. However, it was not observed significant differences between TI and TI-sham or TI and tACS in all N-back tests. Conclusion Our pilot study suggests that TI is a promising technique that can be safely implemented in human participants. Studies are warranted to confirm the findings of this study and to further examine the effects of TI-sham stimulation as well as the effects of TI on deeper brain regions.
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Affiliation(s)
- Yufeng Zhang
- Key Laboratory of Exercise and Health Sciences of Ministry of Education, Shanghai University of Sport, Shanghai, China
| | - Zhining Zhou
- Key Laboratory of Exercise and Health Sciences of Ministry of Education, Shanghai University of Sport, Shanghai, China
| | - Junhong Zhou
- Hebrew SeniorLife, Hinda and Arthur Marcus Institute for Aging Research and Harvard Medical School, Boston, MA, United States
| | - Zhenyu Qian
- Key Laboratory of Exercise and Health Sciences of Ministry of Education, Shanghai University of Sport, Shanghai, China
| | - Jiaojiao Lü
- Key Laboratory of Exercise and Health Sciences of Ministry of Education, Shanghai University of Sport, Shanghai, China
- *Correspondence: Jiaojiao Lü,
| | - Lu Li
- Key Laboratory of Exercise and Health Sciences of Ministry of Education, Shanghai University of Sport, Shanghai, China
- Lu Li,
| | - Yu Liu
- Key Laboratory of Exercise and Health Sciences of Ministry of Education, Shanghai University of Sport, Shanghai, China
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Botzanowski B, Donahue MJ, Ejneby MS, Gallina AL, Ngom I, Missey F, Acerbo E, Byun D, Carron R, Cassarà AM, Neufeld E, Jirsa V, Olofsson PS, Głowacki ED, Williamson A. Noninvasive Stimulation of Peripheral Nerves using Temporally-Interfering Electrical Fields. Adv Healthc Mater 2022; 11:e2200075. [PMID: 35751364 DOI: 10.1002/adhm.202200075] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2022] [Revised: 06/13/2022] [Indexed: 01/27/2023]
Abstract
Electrical stimulation of peripheral nerves is a cornerstone of bioelectronic medicine. Effective ways to accomplish peripheral nerve stimulation (PNS) noninvasively without surgically implanted devices are enabling for fundamental research and clinical translation. Here, it is demonstrated how relatively high-frequency sine-wave carriers (3 kHz) emitted by two pairs of cutaneous electrodes can temporally interfere at deep peripheral nerve targets. The effective stimulation frequency is equal to the offset frequency (0.5 - 4 Hz) between the two carriers. This principle of temporal interference nerve stimulation (TINS) in vivo using the murine sciatic nerve model is validated. Effective actuation is delivered at significantly lower current amplitudes than standard transcutaneous electrical stimulation. Further, how flexible and conformable on-skin multielectrode arrays can facilitate precise alignment of TINS onto a nerve is demonstrated. This method is simple, relying on the repurposing of existing clinically-approved hardware. TINS opens the possibility of precise noninvasive stimulation with depth and efficiency previously impossible with transcutaneous techniques.
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Affiliation(s)
- Boris Botzanowski
- Institut de Neurosciences des Systèmes (INS), INSERM, UMR_1106, Aix-Marseille Université, Marseille, France
| | - Mary J Donahue
- Laboratory of Organic Electronics, Campus Norrköping, Linköping University, Norrköping, Sweden
| | - Malin Silverå Ejneby
- Laboratory of Organic Electronics, Campus Norrköping, Linköping University, Norrköping, Sweden
| | - Alessandro L Gallina
- Laboratory of Immunobiology, Center for Bioelectronic Medicine, Department of Medicine, Solna, Karolinska Institutet, Stockholm, Sweden
| | - Ibrahima Ngom
- Institut de Neurosciences des Systèmes (INS), INSERM, UMR_1106, Aix-Marseille Université, Marseille, France
| | - Florian Missey
- Institut de Neurosciences des Systèmes (INS), INSERM, UMR_1106, Aix-Marseille Université, Marseille, France
| | - Emma Acerbo
- Institut de Neurosciences des Systèmes (INS), INSERM, UMR_1106, Aix-Marseille Université, Marseille, France
| | - Donghak Byun
- Laboratory of Organic Electronics, Campus Norrköping, Linköping University, Norrköping, Sweden
| | - Romain Carron
- Institut de Neurosciences des Systèmes (INS), INSERM, UMR_1106, Aix-Marseille Université, Marseille, France
| | - Antonino M Cassarà
- Foundation for Research on Information Technologies in Society (IT'IS), Zeughaustrasse 43, Zurich, 8004, Switzerland
| | - Esra Neufeld
- Foundation for Research on Information Technologies in Society (IT'IS), Zeughaustrasse 43, Zurich, 8004, Switzerland
| | - Viktor Jirsa
- Institut de Neurosciences des Systèmes (INS), INSERM, UMR_1106, Aix-Marseille Université, Marseille, France
| | - Peder S Olofsson
- Laboratory of Immunobiology, Center for Bioelectronic Medicine, Department of Medicine, Solna, Karolinska Institutet, Stockholm, Sweden.,EMUNE AB, Nanna Svartz väg 6A, Solna, 171 65, Sweden
| | - Eric Daniel Głowacki
- Bioelectronics Materials and Devices Lab, Central European Institute of Technology, Brno University of Technology, Purkyňova 123, Brno, 61200, Czech Republic
| | - Adam Williamson
- Institut de Neurosciences des Systèmes (INS), INSERM, UMR_1106, Aix-Marseille Université, Marseille, France.,Laboratory of Immunobiology, Center for Bioelectronic Medicine, Department of Medicine, Solna, Karolinska Institutet, Stockholm, Sweden
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37
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Stoupis D, Samaras T. Non-invasive stimulation with Temporal Interference: Optimization of the electric field deep in the brain with the use of a genetic algorithm. J Neural Eng 2022; 19. [PMID: 35970146 DOI: 10.1088/1741-2552/ac89b3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2022] [Accepted: 08/15/2022] [Indexed: 11/12/2022]
Abstract
OBJECTIVE Since the introduction of transcranial temporal interference stimulation (tTIS), there has been an ever-growing interest in this novel method, as it theoretically allows non-invasive stimulation of deep brain target regions. To date, attempts have been made to optimize the electrode montages and injected current to achieve personalized area targeting using two electrode pairs. Most of these methods use exhaustive search to find the best match, but faster and, at the same time, reliable solutions are required. In this study, the electrode combinations as well as the injected current for a two-electrode pair stimulation were optimized using a genetic algorithm, considering the right hippocampus as the region of interest (ROI). METHODS Simulations were performed on head models from the Population Head Model (PHM) repository. First, each model was fitted with an electrode array based on the 10-10 international EEG electrode placement system. Following electrode placement, the models were meshed and solved for all single-pair electrode combinations, using an electrode on the left mastoid as a reference (ground). At the optimization stage, different electrode pairs and injection currents were tested using a genetic algorithm to obtain the optimal combination for each model, by setting three different maximum electric field thresholds (0.2, 0.5, and 0.8 V/m) in the ROI. The combinations below the set threshold were given a high penalty. RESULTS Greater focality was achieved with our optimization, specifically in the ROI, with a significant decrease in the surrounding electric field intensity. In the non-optimized case, the mean brain volumes stimulated above 0.2 V/m were 99.9% in the ROI, and 76.4% in the rest of the gray matter. In contrast, the stimulated mean volumes were 91.4% and 29.6%, respectively, for the best optimization case with a threshold of 0.8 V/m. Additionally, the maximum electric field intensity inside the ROI was consistently higher than that outside of the ROI for all optimized cases. SIGNIFICANCE Given that the accomplishment of a globally optimal solution requires a brute-force approach, the use of a genetic algorithm can significantly decrease the optimization time, while achieving personalized deep brain stimulation. The results of this work can be used to facilitate further studies that are more clinically oriented; thus, enabling faster and at the same time accurate treatment planning for the stimulation sessions.
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Affiliation(s)
- D Stoupis
- Department of Physics, Aristotle University of Thessaloniki, University Campus, Thessaloniki, Central Macedonia, 54124, GREECE
| | - T Samaras
- Department of Physics, Aristotle University of Thessaloniki, University Campus, Thessaloniki, 54124, GREECE
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Radyte E, Wendt K, Sorkhabi MM, O'Shea J, Denison T. Relative Comparison of Non-Invasive Brain Stimulation Methods for Modulating Deep Brain Targets. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2022; 2022:1715-1718. [PMID: 36085882 DOI: 10.1109/embc48229.2022.9871476] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
This study models and investigates whether temporally interfering electric fields (TI EFs) could function as an effective non-invasive brain stimulation (NIBS) method for deep brain structure targeting in humans, relevant for psychiatric applications. Here, electric fields off- and on-target are modelled and compared with other common NIBS modalities (tACS, TMS). Additionally, local effects of the field strength are modelled on single-compartment neuronal models. While TI EFs are able to effectively reach deep brain targets, the ratio of off- to on-target stimulation remains high and comparable to other NIBS and may result in off-target neural blocks. Clinical Relevance- This study builds on earlier work and demonstrates some of the challenges -such as off-target conduction blocks- of applying TI EFs for targeting deep brain structures important in understanding the potential of treating neuropsychiatric conditions in the future.
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Jabban L, Ribeiro M, Andreis FR, Dos Santos Nielsen TGN, Metcalfe BW. Pig Ulnar Nerve Recording with Sinusoidal and Temporal Interference Stimulation. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2022; 2022:5084-5088. [PMID: 36086016 DOI: 10.1109/embc48229.2022.9871603] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Temporal interference stimulation has been suggested as a method to reach deep targets during transcutaneous electrical stimulation. Despite its growing use in transcutaneous stimulation therapies, the mechanism of its operation is not fully understood. Recent efforts to fill that gap have focused on computational modelling, in vitro and in vivo experiments relying on physical observations - e.g., sensation or movement. This paper expands the current range of experimental methods by demonstrating in vivo extraneural recordings from the ulnar nerve of a pig while applying temporal interference stimulation at a location targeting a distal part of the nerve. The main aim of the experiment was to compare neural activation using sinusoidal stimulation (100 Hz, 2 kHz, 4 kHz) and temporal interference stimulation (2 kHz and 4 kHz). The recordings showed a significant increase in the magnitude of stimulation artefacts at higher frequencies. While those artefacts could be removed and provided an indication of the depth of modulation, they resulted in the saturation of the amplifiers, limiting the stimulation currents and amplifier gains used. The results of the 100 Hz sine wave stimulation showed clear neural activity correlated to the stimulation waveform. However, this was not observed with temporal interference stimulation. The results suggest that, despite its greater penetration, higher currents might be required to observe a neural response with temporal interference stimulation, and more complex artefact rejection techniques may be required to validate the method.
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40
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Nasr K, Haslacher D, Dayan E, Censor N, Cohen LG, Soekadar SR. Breaking the boundaries of interacting with the human brain using adaptive closed-loop stimulation. Prog Neurobiol 2022; 216:102311. [PMID: 35750290 DOI: 10.1016/j.pneurobio.2022.102311] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2022] [Accepted: 06/20/2022] [Indexed: 11/18/2022]
Abstract
The human brain is arguably one of the most complex systems in nature. To understand how it operates, it is essential to understand the link between neural activity and behavior. Experimental investigation of that link requires tools to interact with neural activity during behavior. Human neuroscience, however, has been severely bottlenecked by the limitations of these tools. While invasive methods can support highly specific interaction with brain activity during behavior, their applicability in human neuroscience is limited. Despite extensive development in the last decades, noninvasive alternatives have lacked spatial specificity and yielded results that are commonly fraught with variability and replicability issues, along with relatively limited understanding of the neural mechanisms involved. Here we provide a comprehensive review of the state-of-the-art in interacting with human brain activity and highlight current limitations and recent efforts to overcome these limitations. Beyond crucial technical and scientific advancements in electromagnetic brain stimulation, new frontiers in interacting with human brain activity such as task-irrelevant sensory stimulation and focal ultrasound stimulation are introduced. Finally, we argue that, along with technological improvements and breakthroughs in noninvasive methods, a paradigm shift towards adaptive closed-loop stimulation will be a critical step for advancing human neuroscience.
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Affiliation(s)
- Khaled Nasr
- Clinical Neurotechnology Laboratory & Center for Translational Neuromodulation, Department of Psychiatry and Neurosciences, Charité Campus Mitte (CCM), Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - David Haslacher
- Clinical Neurotechnology Laboratory & Center for Translational Neuromodulation, Department of Psychiatry and Neurosciences, Charité Campus Mitte (CCM), Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Eran Dayan
- Department of Radiology and Biomedical Research Imaging Center, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Nitzan Censor
- School of Psychological Sciences and Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, Israel
| | - Leonardo G Cohen
- Human Cortical Physiology and Neurorehabilitation Section, National Institutes of Neurological Disorders and Stroke (NINDS), Bethesda, MD, USA
| | - Surjo R Soekadar
- Clinical Neurotechnology Laboratory & Center for Translational Neuromodulation, Department of Psychiatry and Neurosciences, Charité Campus Mitte (CCM), Charité - Universitätsmedizin Berlin, Berlin, Germany.
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Ahsan F, Chi T, Cho R, Sheth SA, Goodman W, Aazhang B. EMvelop stimulation: minimally invasive deep brain stimulation using temporally interfering electromagnetic waves. J Neural Eng 2022; 19. [PMID: 35700717 DOI: 10.1088/1741-2552/ac7894] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2022] [Accepted: 06/14/2022] [Indexed: 11/12/2022]
Abstract
OBJECTIVE Recently, the temporal interference stimulation (TIS) technique for focal noninvasive deep brain stimulation (DBS) was reported. However, subsequent computational modeling studies on the human brain have shown that while TIS achieves higher focality of electric fields than state-of-the-art methods, further work is needed to improve the stimulation strength. Here, we investigate the idea of EMvelop stimulation, a minimally invasive DBS setup using temporally interfering gigahertz (GHz) electromagnetic (EM) waves. At GHz frequencies, we can create antenna arrays at the scale of a few centimeters or less that can be endocranially implanted to enable longitudinal stimulation and circumvent signal attenuation due to the scalp and skull. Furthermore, owing to the small wavelength of GHz EM waves, we can optimize both amplitudes and phases of the EM waves to achieve high intensity and focal stimulation at targeted regions within the safety limit for exposure to EM waves. APPROACH We develop a simulation framework investigating the propagation of GHz EM waves generated by line current antenna elements and the corresponding heat generated in the brain tissue. We propose two optimization flows to identify antenna current amplitudes and phases for either maximal intensity or maximal focality transmission of the interfering electric fields with EM waves safety constraint. MAIN RESULTS A representative result of our study is that with two endocranially implanted arrays of size 4.2 cm × 4.7 cm each, we can achieve an intensity of 12 V/m with a focality of 3.6 cm at a target deep in the brain tissue. SIGNIFICANCE In this proof-of-principle study, we show that the idea of EMvelop stimulation merits further investigation as it can be a minimally invasive way of stimulating deep brain targets and offers benefits not shared by prior methodologies of electrical or magnetic stimulation.
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Affiliation(s)
- Fatima Ahsan
- Electrical and computer engineering, Rice University, 6100 Main Street, Houston, Texas, 77005, UNITED STATES
| | - Taiyun Chi
- Department of Electrical and Computer Engineering and Neuroengineering Initiative, Rice University, 6100 Main Street, Houston, Texas, 77005-1892, UNITED STATES
| | - Raymond Cho
- Menninger Department of Psychiatry and Behavioral Sciences, Baylor College of Medicine, 1 Baylor Plaza, Houston, TX 77030, Houston, Texas, 77030-3411, UNITED STATES
| | - Sameer A Sheth
- Neurosurgery, Baylor College of Medicine, Baylor College of Medicine, Neurosurgery Houston, TX, USA, Houston, Texas, 77030, UNITED STATES
| | - Wayne Goodman
- Psychiatry, Baylor College of Medicine, Baylor College of Medicine, Psychiatry Houston, TX, USA, Houston, Texas, 77030, UNITED STATES
| | - Behnaam Aazhang
- Department of Electrical and Computer Engineering, Rice University, George R. Brown School of Engineering, 6100 Main Street, Houston, TX 77005, USA, Houston, 77005, UNITED STATES
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Zeng Z, Koponen LM, Hamdan R, Li Z, Goetz SM, Peterchev AV. Modular multilevel TMS device with wide output range and ultrabrief pulse capability for sound reduction. J Neural Eng 2022; 19:10.1088/1741-2552/ac572c. [PMID: 35189604 PMCID: PMC9425059 DOI: 10.1088/1741-2552/ac572c] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2021] [Accepted: 02/21/2022] [Indexed: 11/12/2022]
Abstract
Objective.This article presents a novel transcranial magnetic stimulation (TMS) pulse generator with a wide range of pulse shape, amplitude, and width.Approach.Based on a modular multilevel TMS (MM-TMS) topology we had proposed previously, we realized the first such device operating at full TMS energy levels. It consists of ten cascaded H-bridge modules, each implemented with insulated-gate bipolar transistors, enabling both novel high-amplitude ultrabrief pulses as well as pulses with conventional amplitude and duration. The MM-TMS device can output pulses including up to 21 voltage levels with a step size of up to 1100 V, allowing relatively flexible generation of various pulse waveforms and sequences. The circuit further allows charging the energy storage capacitor on each of the ten cascaded modules with a conventional TMS power supply.Main results. The MM-TMS device can output peak coil voltages and currents of 11 kV and 10 kA, respectively, enabling suprathreshold ultrabrief pulses (>8.25μs active electric field phase). Further, the MM-TMS device can generate a wide range of near-rectangular monophasic and biphasic pulses, as well as more complex staircase-approximated sinusoidal, polyphasic, and amplitude-modulated pulses. At matched estimated stimulation strength, briefer pulses emit less sound, which could enable quieter TMS. Finally, the MM-TMS device can instantaneously increase or decrease the amplitude from one pulse to the next in discrete steps by adding or removing modules in series, which enables rapid pulse sequences and paired-pulse protocols with variable pulse shapes and amplitudes.Significance.The MM-TMS device allows unprecedented control of the pulse characteristics which could enable novel protocols and quieter pulses.
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Affiliation(s)
- Zhiyong Zeng
- Department of Psychiatry and Behavioral Sciences, Duke University, Durham, NC, 27710, United States of America
| | - Lari M Koponen
- Department of Psychiatry and Behavioral Sciences, Duke University, Durham, NC, 27710, United States of America
| | - Rena Hamdan
- Department of Psychiatry and Behavioral Sciences, Duke University, Durham, NC, 27710, United States of America
| | - Zhongxi Li
- Department of Electrical and Computer Engineering, Duke University, Durham, NC, 27708, United States of America
| | - Stefan M Goetz
- Department of Psychiatry and Behavioral Sciences, Duke University, Durham, NC, 27710, United States of America.,Department of Electrical and Computer Engineering, Duke University, Durham, NC, 27708, United States of America.,Duke Institute for Brain Sciences, Duke University, Durham, NC, 27708, United States of America.,Department of Neurosurgery, Duke University, Durham, NC, 27710, United States of America
| | - Angel V Peterchev
- Department of Psychiatry and Behavioral Sciences, Duke University, Durham, NC, 27710, United States of America.,Department of Electrical and Computer Engineering, Duke University, Durham, NC, 27708, United States of America.,Duke Institute for Brain Sciences, Duke University, Durham, NC, 27708, United States of America.,Department of Neurosurgery, Duke University, Durham, NC, 27710, United States of America.,Department of Biomedical Engineering, Duke University, Durham, NC, 27708, United States of America
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Ma R, Xia X, Zhang W, Lu Z, Wu Q, Cui J, Song H, Fan C, Chen X, Zha R, Wei J, Ji GJ, Wang X, Qiu B, Zhang X. High Gamma and Beta Temporal Interference Stimulation in the Human Motor Cortex Improves Motor Functions. Front Neurosci 2022; 15:800436. [PMID: 35046771 PMCID: PMC8761631 DOI: 10.3389/fnins.2021.800436] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2021] [Accepted: 11/29/2021] [Indexed: 12/14/2022] Open
Abstract
Background: Temporal interference (TI) stimulation is a new technique of non-invasive brain stimulation. Envelope-modulated waveforms with two high-frequency carriers can activate neurons in target brain regions without stimulating the overlying cortex, which has been validated in mouse brains. However, whether TI stimulation can work on the human brain has not been elucidated. Objective: To assess the effectiveness of the envelope-modulated waveform of TI stimulation on the human primary motor cortex (M1). Methods: Participants attended three sessions of 30-min TI stimulation during a random reaction time task (RRTT) or a serial reaction time task (SRTT). Motor cortex excitability was measured before and after TI stimulation. Results: In the RRTT experiment, only 70 Hz TI stimulation had a promoting effect on the reaction time (RT) performance and excitability of the motor cortex compared to sham stimulation. Meanwhile, compared with the sham condition, only 20 Hz TI stimulation significantly facilitated motor learning in the SRTT experiment, which was significantly positively correlated with the increase in motor evoked potential. Conclusion: These results indicate that the envelope-modulated waveform of TI stimulation has a significant promoting effect on human motor functions, experimentally suggesting the effectiveness of TI stimulation in humans for the first time and paving the way for further explorations.
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Affiliation(s)
- Ru Ma
- Hefei National Laboratory for Physical Sciences at the Microscale, Division of Life Science and Medicine, Department of Radiology, The First Affiliated Hospital of USTC, School of Life Science, University of Science and Technology of China, Hefei, China
| | - Xinzhao Xia
- Centers for Biomedical Engineering, School of Information Science and Technology, University of Science and Technology of China, Hefei, China
| | - Wei Zhang
- Hefei National Laboratory for Physical Sciences at the Microscale, Division of Life Science and Medicine, Department of Radiology, The First Affiliated Hospital of USTC, School of Life Science, University of Science and Technology of China, Hefei, China
| | - Zhuo Lu
- Centers for Biomedical Engineering, School of Information Science and Technology, University of Science and Technology of China, Hefei, China
| | - Qianying Wu
- Hefei National Laboratory for Physical Sciences at the Microscale, Division of Life Science and Medicine, Department of Radiology, The First Affiliated Hospital of USTC, School of Life Science, University of Science and Technology of China, Hefei, China.,Division of the Humanities and Social Sciences, California Institute of Technology, Pasadena, CA, United States
| | - Jiangtian Cui
- Centers for Biomedical Engineering, School of Information Science and Technology, University of Science and Technology of China, Hefei, China.,School of Optometry and Vision Sciences, Cardiff University, Cardiff, United Kingdom
| | - Hongwen Song
- Hefei National Laboratory for Physical Sciences at the Microscale, Division of Life Science and Medicine, Department of Radiology, The First Affiliated Hospital of USTC, School of Life Science, University of Science and Technology of China, Hefei, China
| | - Chuan Fan
- Centers for Biomedical Engineering, School of Information Science and Technology, University of Science and Technology of China, Hefei, China
| | - Xueli Chen
- Hefei National Laboratory for Physical Sciences at the Microscale, Division of Life Science and Medicine, Department of Radiology, The First Affiliated Hospital of USTC, School of Life Science, University of Science and Technology of China, Hefei, China
| | - Rujing Zha
- Hefei National Laboratory for Physical Sciences at the Microscale, Division of Life Science and Medicine, Department of Radiology, The First Affiliated Hospital of USTC, School of Life Science, University of Science and Technology of China, Hefei, China
| | - Junjie Wei
- Department of Neurology, The First Affiliated Hospital of Anhui Medical University, Hefei, China
| | - Gong-Jun Ji
- Department of Neurology, The First Affiliated Hospital of Anhui Medical University, Hefei, China
| | - Xiaoxiao Wang
- Centers for Biomedical Engineering, School of Information Science and Technology, University of Science and Technology of China, Hefei, China
| | - Bensheng Qiu
- Centers for Biomedical Engineering, School of Information Science and Technology, University of Science and Technology of China, Hefei, China
| | - Xiaochu Zhang
- Hefei National Laboratory for Physical Sciences at the Microscale, Division of Life Science and Medicine, Department of Radiology, The First Affiliated Hospital of USTC, School of Life Science, University of Science and Technology of China, Hefei, China.,Centers for Biomedical Engineering, School of Information Science and Technology, University of Science and Technology of China, Hefei, China.,Department of Psychology, School of Humanities and Social Science, University of Science and Technology of China, Hefei, China.,Biomedical Sciences and Health Laboratory of Anhui Province, University of Science and Technology of China, Hefei, China
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44
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Liu X, Qiu F, Hou L, Wang X. Review of Noninvasive or Minimally Invasive Deep Brain Stimulation. Front Behav Neurosci 2022; 15:820017. [PMID: 35145384 PMCID: PMC8823253 DOI: 10.3389/fnbeh.2021.820017] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2021] [Accepted: 12/27/2021] [Indexed: 12/11/2022] Open
Abstract
Brain stimulation is a critical technique in neuroscience research and clinical application. Traditional transcranial brain stimulation techniques, such as transcranial magnetic stimulation (TMS), transcranial direct current stimulation (tDCS), and deep brain stimulation (DBS) have been widely investigated in neuroscience for decades. However, TMS and tDCS have poor spatial resolution and penetration depth, and DBS requires electrode implantation in deep brain structures. These disadvantages have limited the clinical applications of these techniques. Owing to developments in science and technology, substantial advances in noninvasive and precise deep stimulation have been achieved by neuromodulation studies. Second-generation brain stimulation techniques that mainly rely on acoustic, electronic, optical, and magnetic signals, such as focused ultrasound, temporal interference, near-infrared optogenetic, and nanomaterial-enabled magnetic stimulation, offer great prospects for neuromodulation. This review summarized the mechanisms, development, applications, and strengths of these techniques and the prospects and challenges in their development. We believe that these second-generation brain stimulation techniques pave the way for brain disorder therapy.
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Affiliation(s)
- Xiaodong Liu
- School of Kinesiology, Shanghai University of Sport, Shanghai, China
| | - Fang Qiu
- Department of Exercise Physiology, Beijing Sport University, Beijing, China
| | - Lijuan Hou
- College of Physical Education and Sports, Beijing Normal University, Beijing, China
- *Correspondence: Lijuan Hou Xiaohui Wang
| | - Xiaohui Wang
- School of Kinesiology, Shanghai University of Sport, Shanghai, China
- *Correspondence: Lijuan Hou Xiaohui Wang
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45
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Tarnaud T, Joseph W, Schoeters R, Martens L, Tanghe E. Improved alpha-beta power reduction via combined electrical and ultrasonic stimulation in a parkinsonian cortex-basal ganglia-thalamus computational model. J Neural Eng 2021; 18. [PMID: 34874304 DOI: 10.1088/1741-2552/ac3f6d] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2021] [Accepted: 12/02/2021] [Indexed: 11/11/2022]
Abstract
Objective. To investigate computationally the interaction of combined electrical and ultrasonic modulation of isolated neurons and of the parkinsonian cortex-basal ganglia-thalamus loop.Approach. Continuous-wave or pulsed electrical and ultrasonic neuromodulation is applied to isolated Otsuka plateau-potential generating subthalamic nucleus (STN) and Pospischil regular, fast and low-threshold spiking cortical cells in a temporally alternating or simultaneous manner. Similar combinations of electrical/ultrasonic waveforms are applied to a parkinsonian biophysical cortex-basal ganglia-thalamus neuronal network. Ultrasound-neuron interaction is modelled respectively for isolated neurons and the neuronal network with the NICE and SONIC implementations of the bilayer sonophore underlying mechanism. Reduction inα-βspectral energy is used as a proxy to express improvement in Parkinson's disease by insonication and electrostimulation.Main results. Simultaneous electro-acoustic stimulation achieves a given level of neuronal activity at lower intensities compared to the separate stimulation modalities. Conversely, temporally alternating stimulation with50 Hzelectrical and ultrasound pulses is capable of eliciting100 HzSTN firing rates. Furthermore, combination of ultrasound with hyperpolarizing currents can alter cortical cell relative spiking regimes. In the parkinsonian neuronal network, continuous-wave and pulsed ultrasound reduce pathological oscillations by different mechanisms. High-frequency pulsed separated electrical and ultrasonic deep brain stimulation (DBS) reduce pathologicalα-βpower by entraining STN-neurons. In contrast, continuous-wave ultrasound reduces pathological oscillations by silencing the STN. Compared to the separated stimulation modalities, temporally simultaneous or alternating electro-acoustic stimulation can achieve higher reductions inα-βpower for the same safety contraints on electrical/ultrasonic intensity.Significance. Focused ultrasound has the potential of becoming a non-invasive alternative of conventional DBS for the treatment of Parkinson's disease. Here, we elaborate on proposed benefits of combined electro-acoustic stimulation in terms of improved dynamic range, efficiency, spatial resolution, and neuronal selectivity.
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Affiliation(s)
- Thomas Tarnaud
- Department of Information Technology (INTEC-WAVES/IMEC), Ghent University/IMEC, Technologiepark 126Zwijnaarde, 9052, Belgium
| | - Wout Joseph
- Department of Information Technology (INTEC-WAVES/IMEC), Ghent University/IMEC, Technologiepark 126Zwijnaarde, 9052, Belgium
| | - Ruben Schoeters
- Department of Information Technology (INTEC-WAVES/IMEC), Ghent University/IMEC, Technologiepark 126Zwijnaarde, 9052, Belgium
| | - Luc Martens
- Department of Information Technology (INTEC-WAVES/IMEC), Ghent University/IMEC, Technologiepark 126Zwijnaarde, 9052, Belgium
| | - Emmeric Tanghe
- Department of Information Technology (INTEC-WAVES/IMEC), Ghent University/IMEC, Technologiepark 126Zwijnaarde, 9052, Belgium
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46
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Verma N, Graham RD, Mudge J, Trevathan JK, Franke M, Shoffstall AJ, Williams J, Dalrymple AN, Fisher LE, Weber DJ, Lempka SF, Ludwig KA. Augmented Transcutaneous Stimulation Using an Injectable Electrode: A Computational Study. Front Bioeng Biotechnol 2021; 9:796042. [PMID: 34988068 PMCID: PMC8722711 DOI: 10.3389/fbioe.2021.796042] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2021] [Accepted: 11/25/2021] [Indexed: 11/13/2022] Open
Abstract
Minimally invasive neuromodulation technologies seek to marry the neural selectivity of implantable devices with the low-cost and non-invasive nature of transcutaneous electrical stimulation (TES). The Injectrode® is a needle-delivered electrode that is injected onto neural structures under image guidance. Power is then transcutaneously delivered to the Injectrode using surface electrodes. The Injectrode serves as a low-impedance conduit to guide current to the deep on-target nerve, reducing activation thresholds by an order of magnitude compared to using only surface stimulation electrodes. To minimize off-target recruitment of cutaneous fibers, the energy transfer efficiency from the surface electrodes to the Injectrode must be optimized. TES energy is transferred to the Injectrode through both capacitive and resistive mechanisms. Electrostatic finite element models generally used in TES research consider only the resistive means of energy transfer by defining tissue conductivities. Here, we present an electroquasistatic model, taking into consideration both the conductivity and permittivity of tissue, to understand transcutaneous power delivery to the Injectrode. The model was validated with measurements taken from (n = 4) swine cadavers. We used the validated model to investigate system and anatomic parameters that influence the coupling efficiency of the Injectrode energy delivery system. Our work suggests the relevance of electroquasistatic models to account for capacitive charge transfer mechanisms when studying TES, particularly when high-frequency voltage components are present, such as those used for voltage-controlled pulses and sinusoidal nerve blocks.
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Affiliation(s)
- Nishant Verma
- Department of Biomedical Engineering, University of Wisconsin–Madison, Madison, WI, United States
- Wisconsin Institute for Translational Neuroengineering (WITNe)–Madison, Madison, WI, United States
| | - Robert D. Graham
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, United States
- Biointerfaces Institute, University of Michigan, Ann Arbor, MI, United States
| | - Jonah Mudge
- Department of Biomedical Engineering, University of Wisconsin–Madison, Madison, WI, United States
- Wisconsin Institute for Translational Neuroengineering (WITNe)–Madison, Madison, WI, United States
| | - James K. Trevathan
- Department of Biomedical Engineering, University of Wisconsin–Madison, Madison, WI, United States
- Wisconsin Institute for Translational Neuroengineering (WITNe)–Madison, Madison, WI, United States
| | | | - Andrew J Shoffstall
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, United States
| | - Justin Williams
- Department of Biomedical Engineering, University of Wisconsin–Madison, Madison, WI, United States
- Wisconsin Institute for Translational Neuroengineering (WITNe)–Madison, Madison, WI, United States
| | - Ashley N. Dalrymple
- Department of Mechanical Engineering, Carnegie Mellon University, Pittsburgh, PA, United States
- Rehab Neural Engineering Labs (RNEL), Department of Physical Medicine and Rehabilitation, University of Pittsburgh, Pittsburgh, PA, United States
| | - Lee E. Fisher
- Rehab Neural Engineering Labs (RNEL), Department of Physical Medicine and Rehabilitation, University of Pittsburgh, Pittsburgh, PA, United States
| | - Douglas J. Weber
- Department of Mechanical Engineering, Carnegie Mellon University, Pittsburgh, PA, United States
- Rehab Neural Engineering Labs (RNEL), Department of Physical Medicine and Rehabilitation, University of Pittsburgh, Pittsburgh, PA, United States
| | - Scott F. Lempka
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, United States
- Biointerfaces Institute, University of Michigan, Ann Arbor, MI, United States
- Department of Anesthesiology, University of Michigan, Ann Arbor, MI, United States
| | - Kip A. Ludwig
- Department of Biomedical Engineering, University of Wisconsin–Madison, Madison, WI, United States
- Wisconsin Institute for Translational Neuroengineering (WITNe)–Madison, Madison, WI, United States
- Department of Neurosurgery, University of Wisconsin–Madison, Madison, WI, United States
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47
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Xin Z, Kuwahata A, Liu S, Sekino M. Magnetically Induced Temporal Interference for Focal and Deep-Brain Stimulation. Front Hum Neurosci 2021; 15:693207. [PMID: 34646125 PMCID: PMC8502936 DOI: 10.3389/fnhum.2021.693207] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2021] [Accepted: 08/18/2021] [Indexed: 11/13/2022] Open
Abstract
Transcranial magnetic stimulation (TMS) is a non-invasive brain stimulation technique that has been clinically applied for neural modulation. Conventional TMS systems are restricted by the trade-off between depth penetration and the focality of the induced electric field. In this study, we integrated the concept of temporal interference (TI) stimulation, which has been demonstrated as a non-invasive deep-brain stimulation method, with magnetic stimulation in a four-coil configuration. The attenuation depth and spread of the electric field were obtained by performing numerical simulation. Consequently, the proposed temporally interfered magnetic stimulation scheme was demonstrated to be capable of stimulating deeper regions of the brain model while maintaining a relatively narrow spread of the electric field, in comparison to conventional TMS systems. These results demonstrate that TI magnetic stimulation could be a potential candidate to recruit brain regions underneath the cortex. Additionally, by controlling the geometry of the coil array, an analogous relationship between the field depth and focality was observed, in the case of the newly proposed method. The major limitations of the methods, however, would be the considerable intensity and frequency of the input current, followed by the frustration in the thermal management of the hardware.
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Affiliation(s)
- Zonghao Xin
- Laboratory Sekino, Department of Bioengineering, School of Engineering, The University of Tokyo, Tokyo, Japan
| | - Akihiro Kuwahata
- Laboratory Sekino, Department of Electrical Engineering and Information Systems, Graduate School of Engineering, The University of Tokyo, Tokyo, Japan
| | - Shuang Liu
- Laboratory Sekino, Department of Electrical Engineering and Information Systems, Graduate School of Engineering, The University of Tokyo, Tokyo, Japan
| | - Masaki Sekino
- Laboratory Sekino, Department of Bioengineering, School of Engineering, The University of Tokyo, Tokyo, Japan
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48
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von Conta J, Kasten FH, Ćurčić-Blake B, Aleman A, Thielscher A, Herrmann CS. Interindividual variability of electric fields during transcranial temporal interference stimulation (tTIS). Sci Rep 2021; 11:20357. [PMID: 34645895 PMCID: PMC8514596 DOI: 10.1038/s41598-021-99749-0] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Accepted: 09/27/2021] [Indexed: 12/12/2022] Open
Abstract
Transcranial temporal interference stimulation (tTIS) is a novel non-invasive brain stimulation technique for electrical stimulation of neurons at depth. Deep brain regions are generally small in size, making precise targeting a necessity. The variability of electric fields across individual subjects resulting from the same tTIS montages is unknown so far and may be of major concern for precise tTIS targeting. Therefore, the aim of the current study is to investigate the variability of the electric fields due to tTIS across 25 subjects. To this end, the electric fields of different electrode montages consisting of two electrode pairs with different center frequencies were simulated in order to target selected regions-of-interest (ROIs) with tTIS. Moreover, we set out to compare the electric fields of tTIS with the electric fields of conventional tACS. The latter were also based on two electrode pairs, which, however, were driven in phase at a common frequency. Our results showed that the electric field strengths inside the ROIs (left hippocampus, left motor area and thalamus) during tTIS are variable on single subject level. In addition, tTIS stimulates more focally as compared to tACS with much weaker co-stimulation of cortical areas close to the stimulation electrodes. Electric fields inside the ROI were, however, comparable for both methods. Overall, our results emphasize the potential benefits of tTIS for the stimulation of deep targets, over conventional tACS. However, they also indicate a need for individualized stimulation montages to leverage the method to its fullest potential.
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Affiliation(s)
- Jill von Conta
- Experimental Psychology Lab, Department of Psychology, European Medical School, Cluster of Excellence "Hearing4All", Carl Von Ossietzky University, Ammerländer Heerstr. 114-118, 26129, Oldenburg, Germany
| | - Florian H Kasten
- Experimental Psychology Lab, Department of Psychology, European Medical School, Cluster of Excellence "Hearing4All", Carl Von Ossietzky University, Ammerländer Heerstr. 114-118, 26129, Oldenburg, Germany.,Neuroimaging Unit, European Medical School, Carl Von Ossietzky University, Oldenburg, Germany
| | - Branislava Ćurčić-Blake
- Department of Biomedical Sciences of Cells and Systems, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - André Aleman
- Department of Biomedical Sciences of Cells and Systems, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Axel Thielscher
- Danish Research Centre for Magnetic Resonance, Center for Functional and Diagnostic Imaging and Research, Copenhagen University Hospital Amager and Hvidovre, Copenhagen, Denmark.,Center for Magnetic Resonance, DTU Health Tech, Technical University of Denmark, Kgs Lyngby, Denmark
| | - Christoph S Herrmann
- Experimental Psychology Lab, Department of Psychology, European Medical School, Cluster of Excellence "Hearing4All", Carl Von Ossietzky University, Ammerländer Heerstr. 114-118, 26129, Oldenburg, Germany. .,Neuroimaging Unit, European Medical School, Carl Von Ossietzky University, Oldenburg, Germany. .,Research Center Neurosensory Science, Carl Von Ossietzky University, Oldenburg, Germany.
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49
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Jones MG, Rogers ER, Harris JP, Sullivan A, Ackermann DM, Russo M, Lempka SF, McMahon SB. Neuromodulation using ultra low frequency current waveform reversibly blocks axonal conduction and chronic pain. Sci Transl Med 2021; 13:13/608/eabg9890. [PMID: 34433642 DOI: 10.1126/scitranslmed.abg9890] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2021] [Accepted: 06/22/2021] [Indexed: 01/02/2023]
Abstract
Chronic pain remains a leading cause of disability worldwide, and there is still a clinical reliance on opioids despite the medical side effects associated with their use and societal impacts associated with their abuse. An alternative approach is the use of electrical neuromodulation to produce analgesia. Direct current can block action potential propagation but leads to tissue damage if maintained. We have developed a form of ultra low frequency (ULF) biphasic current and studied its effects. In anesthetized rats, this waveform produced a rapidly developing and completely reversible conduction block in >85% of spinal sensory nerve fibers excited by peripheral stimulation. Sustained ULF currents at lower amplitudes led to a slower onset but reversible conduction block. Similar changes were seen in an animal model of neuropathic pain, where ULF waveforms blocked sensory neuron ectopic activity, known to be an important driver of clinical neuropathic pain. Using a computational model, we showed that prolonged ULF currents could induce accumulation of extracellular potassium, accounting for the slowly developing block observed in rats. Last, we tested the analgesic effects of epidural ULF currents in 20 subjects with chronic leg and back pain. Pain ratings improved by 90% after 2 weeks. One week after explanting the electrodes, pain ratings reverted to 72% of pretreatment screening value. We conclude that epidural spinal ULF neuromodulation represents a promising therapy for treating chronic pain.
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Affiliation(s)
- Martyn G Jones
- Zenith NeuroTech Ltd., King's College London, London SE1 1UL, UK.,Wolfson CARD, King's College London, London SE1 1UL, UK
| | - Evan R Rogers
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI 48109, USA.,Biointerfaces Institute, University of Michigan, Ann Arbor, MI 48109, USA
| | - James P Harris
- Presidio Medical Inc., Oyster Point Blvd., South San Francisco, CA 94080, USA
| | - Andrew Sullivan
- Presidio Medical Inc., Oyster Point Blvd., South San Francisco, CA 94080, USA
| | - D Michael Ackermann
- Presidio Medical Inc., Oyster Point Blvd., South San Francisco, CA 94080, USA
| | - Marc Russo
- Hunter Pain Clinic, Broadmeadow, New South Wales 2292, Australia
| | - Scott F Lempka
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI 48109, USA.,Biointerfaces Institute, University of Michigan, Ann Arbor, MI 48109, USA.,Department of Anesthesiology, University of Michigan, Ann Arbor, MI 48109, USA
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50
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Gomez-Tames J, Asai A, Hirata A. Multiscale Computational Model Reveals Nerve Response in a Mouse Model for Temporal Interference Brain Stimulation. Front Neurosci 2021; 15:684465. [PMID: 34276293 PMCID: PMC8277927 DOI: 10.3389/fnins.2021.684465] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2021] [Accepted: 06/08/2021] [Indexed: 12/24/2022] Open
Abstract
There has been a growing interest in the non-invasive stimulation of specific brain tissues, while reducing unintended stimulation in surrounding regions, for the medical treatment of brain disorders. Traditional methods for non-invasive brain stimulation, such as transcranial direct current stimulation (tDCS) or transcranial magnetic stimulation (TMS), can stimulate brain regions, but they also simultaneously stimulate the brain and non-brain regions that lie between the target and the stimulation site of the source. Temporal interference (TI) stimulation has been suggested to selectively stimulate brain regions by superposing two alternating currents with slightly different frequencies injected through electrodes attached to the scalp. Previous studies have reported promising results for TI applied to the motor area in mice, but the mechanisms are yet to be clarified. As computational techniques can help reveal different aspects of TI, in this study, we computationally investigated TI stimulation using a multiscale model that computes the generated interference current pattern effects in a neural cortical model of a mouse head. The results indicated that the threshold increased with the carrier frequency and that the beat frequency did not influence the threshold. It was also found that the intensity ratio between the alternating currents changed the location of the responding nerve, which is in agreement with previous experiments. Moreover, particular characteristics of the envelope were investigated to predict the stimulation region intuitively. It was found that regions with high modulation depth (| maximum| − | minimum| values of the envelope) and low minimum envelope (near zero) corresponded with the activation region obtained via neural computation.
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Affiliation(s)
- Jose Gomez-Tames
- Department of Electrical and Mechanical Engineering, Nagoya Institute of Technology, Nagoya, Japan.,Center of Biomedical Physics and Information Technology, Nagoya Institute of Technology, Nagoya, Japan
| | - Akihiro Asai
- Department of Electrical and Mechanical Engineering, Nagoya Institute of Technology, Nagoya, Japan
| | - Akimasa Hirata
- Department of Electrical and Mechanical Engineering, Nagoya Institute of Technology, Nagoya, Japan.,Center of Biomedical Physics and Information Technology, Nagoya Institute of Technology, Nagoya, Japan
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