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Chen FD, Sharma A, Roszko DA, Xue T, Mu X, Luo X, Chua H, Lo PGQ, Sacher WD, Poon JKS. Development of wafer-scale multifunctional nanophotonic neural probes for brain activity mapping. Lab Chip 2024; 24:2397-2417. [PMID: 38623840 DOI: 10.1039/d3lc00931a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/17/2024]
Abstract
Optical techniques, such as optogenetic stimulation and functional fluorescence imaging, have been revolutionary for neuroscience by enabling neural circuit analysis with cell-type specificity. To probe deep brain regions, implantable light sources are crucial. Silicon photonics, commonly used for data communications, shows great promise in creating implantable devices with complex optical systems in a compact form factor compatible with high volume manufacturing practices. This article reviews recent developments of wafer-scale multifunctional nanophotonic neural probes. The probes can be realized on 200 or 300 mm wafers in commercial foundries and integrate light emitters for photostimulation, microelectrodes for electrophysiological recording, and microfluidic channels for chemical delivery and sampling. By integrating active optical devices to the probes, denser emitter arrays, enhanced on-chip biosensing, and increased ease of use may be realized. Silicon photonics technology makes possible highly versatile implantable neural probes that can transform neuroscience experiments.
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Affiliation(s)
- Fu Der Chen
- Max Planck Institute of Microstructure Physics, Weinberg 2, 06120 Halle, Germany.
- Department of Electrical and Computer Engineering, University of Toronto, 10 King's College Road, Toronto, Ontario M5S 3G4, Canada
| | - Ankita Sharma
- Max Planck Institute of Microstructure Physics, Weinberg 2, 06120 Halle, Germany.
- Department of Electrical and Computer Engineering, University of Toronto, 10 King's College Road, Toronto, Ontario M5S 3G4, Canada
| | - David A Roszko
- Max Planck Institute of Microstructure Physics, Weinberg 2, 06120 Halle, Germany.
- Department of Electrical and Computer Engineering, University of Toronto, 10 King's College Road, Toronto, Ontario M5S 3G4, Canada
| | - Tianyuan Xue
- Max Planck Institute of Microstructure Physics, Weinberg 2, 06120 Halle, Germany.
- Department of Electrical and Computer Engineering, University of Toronto, 10 King's College Road, Toronto, Ontario M5S 3G4, Canada
| | - Xin Mu
- Max Planck Institute of Microstructure Physics, Weinberg 2, 06120 Halle, Germany.
- Department of Electrical and Computer Engineering, University of Toronto, 10 King's College Road, Toronto, Ontario M5S 3G4, Canada
| | - Xianshu Luo
- Advanced Micro Foundry Pte Ltd, 11 Science Park Road, Singapore Science Park II, 117685, Singapore
| | - Hongyao Chua
- Advanced Micro Foundry Pte Ltd, 11 Science Park Road, Singapore Science Park II, 117685, Singapore
| | - Patrick Guo-Qiang Lo
- Advanced Micro Foundry Pte Ltd, 11 Science Park Road, Singapore Science Park II, 117685, Singapore
| | - Wesley D Sacher
- Max Planck Institute of Microstructure Physics, Weinberg 2, 06120 Halle, Germany.
| | - Joyce K S Poon
- Max Planck Institute of Microstructure Physics, Weinberg 2, 06120 Halle, Germany.
- Department of Electrical and Computer Engineering, University of Toronto, 10 King's College Road, Toronto, Ontario M5S 3G4, Canada
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Altan E, Solla SA, Miller LE, Perreault EJ. Estimating the dimensionality of the manifold underlying multi-electrode neural recordings. PLoS Comput Biol 2021; 17:e1008591. [PMID: 34843461 PMCID: PMC8659648 DOI: 10.1371/journal.pcbi.1008591] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2020] [Revised: 12/09/2021] [Accepted: 11/11/2021] [Indexed: 01/07/2023] Open
Abstract
It is generally accepted that the number of neurons in a given brain area far exceeds the number of neurons needed to carry any specific function controlled by that area. For example, motor areas of the human brain contain tens of millions of neurons that control the activation of tens or at most hundreds of muscles. This massive redundancy implies the covariation of many neurons, which constrains the population activity to a low-dimensional manifold within the space of all possible patterns of neural activity. To gain a conceptual understanding of the complexity of the neural activity within a manifold, it is useful to estimate its dimensionality, which quantifies the number of degrees of freedom required to describe the observed population activity without significant information loss. While there are many algorithms for dimensionality estimation, we do not know which are well suited for analyzing neural activity. The objective of this study was to evaluate the efficacy of several representative algorithms for estimating the dimensionality of linearly and nonlinearly embedded data. We generated synthetic neural recordings with known intrinsic dimensionality and used them to test the algorithms' accuracy and robustness. We emulated some of the important challenges associated with experimental data by adding noise, altering the nature of the embedding of the low-dimensional manifold within the high-dimensional recordings, varying the dimensionality of the manifold, and limiting the amount of available data. We demonstrated that linear algorithms overestimate the dimensionality of nonlinear, noise-free data. In cases of high noise, most algorithms overestimated the dimensionality. We thus developed a denoising algorithm based on deep learning, the "Joint Autoencoder", which significantly improved subsequent dimensionality estimation. Critically, we found that all algorithms failed when the intrinsic dimensionality was high (above 20) or when the amount of data used for estimation was low. Based on the challenges we observed, we formulated a pipeline for estimating the dimensionality of experimental neural data.
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Affiliation(s)
- Ege Altan
- Department of Neuroscience, Northwestern University, Chicago, Illinois, United States of America
- Department of Biomedical Engineering, Northwestern University, Evanston, Illinois, United States of America
| | - Sara A. Solla
- Department of Neuroscience, Northwestern University, Chicago, Illinois, United States of America
- Department of Physics and Astronomy, Northwestern University, Evanston, Illinois, United States of America
| | - Lee E. Miller
- Department of Neuroscience, Northwestern University, Chicago, Illinois, United States of America
- Department of Biomedical Engineering, Northwestern University, Evanston, Illinois, United States of America
- Department of Physical Medicine and Rehabilitation, Northwestern University, Chicago, Illinois, United States of America
- Shirley Ryan AbilityLab, Chicago, Illinois, United States of America
| | - Eric J. Perreault
- Department of Biomedical Engineering, Northwestern University, Evanston, Illinois, United States of America
- Department of Physical Medicine and Rehabilitation, Northwestern University, Chicago, Illinois, United States of America
- Shirley Ryan AbilityLab, Chicago, Illinois, United States of America
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Hansen BC, Greene MR, Field DJ. Dynamic Electrode-to-Image (DETI) mapping reveals the human brain's spatiotemporal code of visual information. PLoS Comput Biol 2021; 17:e1009456. [PMID: 34570753 PMCID: PMC8496831 DOI: 10.1371/journal.pcbi.1009456] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2021] [Revised: 10/07/2021] [Accepted: 09/16/2021] [Indexed: 11/18/2022] Open
Abstract
A number of neuroimaging techniques have been employed to understand how visual information is transformed along the visual pathway. Although each technique has spatial and temporal limitations, they can each provide important insights into the visual code. While the BOLD signal of fMRI can be quite informative, the visual code is not static and this can be obscured by fMRI’s poor temporal resolution. In this study, we leveraged the high temporal resolution of EEG to develop an encoding technique based on the distribution of responses generated by a population of real-world scenes. This approach maps neural signals to each pixel within a given image and reveals location-specific transformations of the visual code, providing a spatiotemporal signature for the image at each electrode. Our analyses of the mapping results revealed that scenes undergo a series of nonuniform transformations that prioritize different spatial frequencies at different regions of scenes over time. This mapping technique offers a potential avenue for future studies to explore how dynamic feedforward and recurrent processes inform and refine high-level representations of our visual world. The visual information that we sample from our environment undergoes a series of neural modifications, with each modification state (or visual code) consisting of a unique distribution of responses across neurons along the visual pathway. However, current noninvasive neuroimaging techniques provide an account of that code that is coarse with respect to time or space. Here, we present dynamic electrode-to-image (DETI) mapping, an analysis technique that capitalizes on the high temporal resolution of EEG to map neural signals to each pixel within a given image to reveal location-specific modifications of the visual code. The DETI technique reveals maps of features that are associated with the neural signal at each pixel and at each time point. DETI mapping shows that real-world scenes undergo a series of nonuniform modifications over both space and time. Specifically, we find that the visual code varies in a location-specific manner, likely reflecting that neural processing prioritizes different features at different image locations over time. DETI mapping therefore offers a potential avenue for future studies to explore how each modification state informs and refines the conceptual meaning of our visual world.
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Affiliation(s)
- Bruce C. Hansen
- Colgate University, Department of Psychological & Brain Sciences, Neuroscience Program, Hamilton New York, United States of America
- * E-mail:
| | - Michelle R. Greene
- Bates College, Neuroscience Program, Lewiston, Maine, United States of America
| | - David J. Field
- Cornell University, Department of Psychology, Ithaca, New York, United States of America
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McKnight JC, Ruesch A, Bennett K, Bronkhorst M, Balfour S, Moss SEW, Milne R, Tyack PL, Kainerstorfer JM, Hastie GD. Shining new light on sensory brain activation and physiological measurement in seals using wearable optical technology. Philos Trans R Soc Lond B Biol Sci 2021; 376:20200224. [PMID: 34121458 PMCID: PMC8200653 DOI: 10.1098/rstb.2020.0224] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/23/2020] [Indexed: 12/19/2022] Open
Abstract
Sensory ecology and physiology of free-ranging animals is challenging to study but underpins our understanding of decision-making in the wild. Existing non-invasive human biomedical technology offers tools that could be harnessed to address these challenges. Functional near-infrared spectroscopy (fNIRS), a wearable, non-invasive biomedical imaging technique measures oxy- and deoxyhaemoglobin concentration changes that can be used to detect localized neural activation in the brain. We tested the efficacy of fNIRS to detect cortical activation in grey seals (Halichoerus grypus) and identify regions of the cortex associated with different senses (vision, hearing and touch). The activation of specific cerebral areas in seals was detected by fNIRS in responses to light (vision), sound (hearing) and whisker stimulation (touch). Physiological parameters, including heart and breathing rate, were also extracted from the fNIRS signal, which allowed neural and physiological responses to be monitored simultaneously. This is, to our knowledge, the first time fNIRS has been used to detect cortical activation in a non-domesticated or laboratory animal. Because fNIRS is non-invasive and wearable, this study demonstrates its potential as a tool to quantitatively investigate sensory perception and brain function while simultaneously recording heart rate, tissue and arterial oxygen saturation of haemoglobin, perfusion changes and breathing rate in free-ranging animals. This article is part of the theme issue 'Measuring physiology in free-living animals (Part I)'.
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Affiliation(s)
- J. Chris McKnight
- Sea Mammal Research Unit, Scottish Oceans Institute, University of St Andrews, St Andrews, UK
| | - Alexander Ruesch
- Department of Biomedical Engineering, Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh, PA 15213, USA
| | - Kimberley Bennett
- Division of Science, School of Engineering and Technology, Abertay University, Dundee, UK
| | - Mathijs Bronkhorst
- Artinis Medical Systems BV, Einsteinweg 17, 6662 PW Elst, The Netherlands
| | - Steve Balfour
- Sea Mammal Research Unit Instrumentation Group, Scottish Oceans Institute, University of St Andrews, St Andrews, UK
| | - Simon E. W. Moss
- Sea Mammal Research Unit, Scottish Oceans Institute, University of St Andrews, St Andrews, UK
| | - Ryan Milne
- Sea Mammal Research Unit, Scottish Oceans Institute, University of St Andrews, St Andrews, UK
| | - Peter L. Tyack
- Sea Mammal Research Unit, Scottish Oceans Institute, University of St Andrews, St Andrews, UK
| | - Jana M. Kainerstorfer
- Department of Biomedical Engineering, Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh, PA 15213, USA
- Department of Biomedical Engineering, Carnegie Mellon University, 5000 Forbes Ave., Pittsburgh, PA 15213, USA
| | - Gordon D. Hastie
- Sea Mammal Research Unit, Scottish Oceans Institute, University of St Andrews, St Andrews, UK
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Liu P, Chrysidou A, Doehler J, Hebart MN, Wolbers T, Kuehn E. The organizational principles of de-differentiated topographic maps in somatosensory cortex. eLife 2021; 10:e60090. [PMID: 34003108 PMCID: PMC8186903 DOI: 10.7554/elife.60090] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Accepted: 05/17/2021] [Indexed: 01/09/2023] Open
Abstract
Topographic maps are a fundamental feature of cortex architecture in the mammalian brain. One common theory is that the de-differentiation of topographic maps links to impairments in everyday behavior due to less precise functional map readouts. Here, we tested this theory by characterizing de-differentiated topographic maps in primary somatosensory cortex (SI) of younger and older adults by means of ultra-high resolution functional magnetic resonance imaging together with perceptual finger individuation and hand motor performance. Older adults' SI maps showed similar amplitude and size to younger adults' maps, but presented with less representational similarity between distant fingers. Larger population receptive field sizes in older adults' maps did not correlate with behavior, whereas reduced cortical distances between D2 and D3 related to worse finger individuation but better motor performance. Our data uncover the drawbacks of a simple de-differentiation model of topographic map function, and motivate the introduction of feature-based models of cortical reorganization.
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Affiliation(s)
- Peng Liu
- Institute for Cognitive Neurology and Dementia Research (IKND), Otto-von-Guericke University MagdeburgMagdeburgGermany
- German Center for Neurodegenerative Diseases (DZNE)MagdeburgGermany
| | - Anastasia Chrysidou
- Institute for Cognitive Neurology and Dementia Research (IKND), Otto-von-Guericke University MagdeburgMagdeburgGermany
- German Center for Neurodegenerative Diseases (DZNE)MagdeburgGermany
| | - Juliane Doehler
- Institute for Cognitive Neurology and Dementia Research (IKND), Otto-von-Guericke University MagdeburgMagdeburgGermany
- German Center for Neurodegenerative Diseases (DZNE)MagdeburgGermany
| | - Martin N Hebart
- Vision and Computational Cognition Group, Max Planck Institute for Human Cognitive and Brain SciencesLeipzigGermany
| | - Thomas Wolbers
- German Center for Neurodegenerative Diseases (DZNE)MagdeburgGermany
- Center for Behavioral Brain Sciences (CBBS) MagdeburgMagdeburgGermany
| | - Esther Kuehn
- Institute for Cognitive Neurology and Dementia Research (IKND), Otto-von-Guericke University MagdeburgMagdeburgGermany
- German Center for Neurodegenerative Diseases (DZNE)MagdeburgGermany
- Center for Behavioral Brain Sciences (CBBS) MagdeburgMagdeburgGermany
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Koush Y, de Graaf RA, Kupers R, Dricot L, Ptito M, Behar KL, Rothman DL, Hyder F. Metabolic underpinnings of activated and deactivated cortical areas in human brain. J Cereb Blood Flow Metab 2021; 41:986-1000. [PMID: 33472521 PMCID: PMC8054719 DOI: 10.1177/0271678x21989186] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/22/2020] [Revised: 11/04/2020] [Accepted: 12/11/2020] [Indexed: 11/16/2022]
Abstract
Neuroimaging with functional MRI (fMRI) identifies activated and deactivated brain regions in task-based paradigms. These patterns of (de)activation are altered in diseases, motivating research to understand their underlying biochemical/biophysical mechanisms. Essentially, it remains unknown how aerobic metabolism of glucose to lactate (aerobic glycolysis) and excitatory-inhibitory balance of glutamatergic and GABAergic neuronal activities vary in these areas. In healthy volunteers, we investigated metabolic distinctions of activating visual cortex (VC, a task-positive area) using a visual task and deactivating posterior cingulate cortex (PCC, a task-negative area) using a cognitive task. We used fMRI-guided J-edited functional MRS (fMRS) to measure lactate, glutamate plus glutamine (Glx) and γ-aminobutyric acid (GABA), as indicators of aerobic glycolysis and excitatory-inhibitory balance, respectively. Both lactate and Glx increased upon activating VC, but did not change upon deactivating PCC. Basal GABA was negatively correlated with BOLD responses in both brain areas, but during functional tasks GABA decreased in VC upon activation and GABA increased in PCC upon deactivation, suggesting BOLD responses in relation to baseline are impacted oppositely by task-induced inhibition. In summary, opposite relations between BOLD response and GABAergic inhibition, and increases in aerobic glycolysis and glutamatergic activity distinguish the BOLD response in (de)activated areas.
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Affiliation(s)
- Yury Koush
- Magnetic Resonance Research Center, Department of Radiology & Biomedical Imaging, Yale University, New Haven, CT, USA
| | - Robin A de Graaf
- Magnetic Resonance Research Center, Department of Radiology & Biomedical Imaging, Yale University, New Haven, CT, USA
- Department of Biomedical Engineering, Yale University, New Haven, CT, USA
| | - Ron Kupers
- BRAINlab, Department of Neuroscience, Panum Institute, University of Copenhagen, Copenhagen, Denmark
| | - Laurence Dricot
- Institute of NeuroScience (IoNS), Université catholique de Louvain (UCLouvain), Belgium
| | - Maurice Ptito
- School of Optometry, Université de Montreal, Montreal, Canada
| | - Kevin L Behar
- Magnetic Resonance Research Center, Department of Radiology & Biomedical Imaging, Yale University, New Haven, CT, USA
- Department of Psychiatry, Yale University, New Haven, CT, USA
| | - Douglas L Rothman
- Magnetic Resonance Research Center, Department of Radiology & Biomedical Imaging, Yale University, New Haven, CT, USA
- Department of Biomedical Engineering, Yale University, New Haven, CT, USA
| | - Fahmeed Hyder
- Magnetic Resonance Research Center, Department of Radiology & Biomedical Imaging, Yale University, New Haven, CT, USA
- Department of Biomedical Engineering, Yale University, New Haven, CT, USA
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7
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Fallegger F, Schiavone G, Pirondini E, Wagner FB, Vachicouras N, Serex L, Zegarek G, May A, Constanthin P, Palma M, Khoshnevis M, Van Roost D, Yvert B, Courtine G, Schaller K, Bloch J, Lacour SP. MRI-Compatible and Conformal Electrocorticography Grids for Translational Research. Adv Sci (Weinh) 2021; 8:2003761. [PMID: 33977054 PMCID: PMC8097365 DOI: 10.1002/advs.202003761] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2020] [Revised: 12/23/2020] [Indexed: 05/23/2023]
Abstract
Intraoperative electrocorticography (ECoG) captures neural information from the surface of the cerebral cortex during surgeries such as resections for intractable epilepsy and tumors. Current clinical ECoG grids come in evenly spaced, millimeter-sized electrodes embedded in silicone rubber. Their mechanical rigidity and fixed electrode spatial resolution are common shortcomings reported by the surgical teams. Here, advances in soft neurotechnology are leveraged to manufacture conformable subdural, thin-film ECoG grids, and evaluate their suitability for translational research. Soft grids with 0.2 to 10 mm electrode pitch and diameter are embedded in 150 µm silicone membranes. The soft grids are compatible with surgical handling and can be folded to safely interface hidden cerebral surface such as the Sylvian fold in human cadaveric models. It is found that the thin-film conductor grids do not generate diagnostic-impeding imaging artefacts (<1 mm) nor adverse local heating within a standard 3T clinical magnetic resonance imaging scanner. Next, the ability of the soft grids to record subdural neural activity in minipigs acutely and two weeks postimplantation is validated. Taken together, these results suggest a promising future alternative to current stiff electrodes and may enable the future adoption of soft ECoG grids in translational research and ultimately in clinical settings.
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Affiliation(s)
- Florian Fallegger
- Bertarelli Foundation Chair in Neuroprosthetic TechnologyLaboratory for Soft Bioelectronic InterfacesInstitute of MicroengineeringInstitute of BioengineeringCenter for NeuroprostheticsEcole Polytechnique Fédérale de Lausanne (EPFL)Geneva1202Switzerland
| | - Giuseppe Schiavone
- Bertarelli Foundation Chair in Neuroprosthetic TechnologyLaboratory for Soft Bioelectronic InterfacesInstitute of MicroengineeringInstitute of BioengineeringCenter for NeuroprostheticsEcole Polytechnique Fédérale de Lausanne (EPFL)Geneva1202Switzerland
| | - Elvira Pirondini
- Department of NeurosurgeryUniversity Hospital of Lausanne (CHUV) and University of Lausanne (UNIL)Lausanne1010Switzerland
- Defitech Center for Interventional Neurotherapies (NeuroRestore)Department of NeurosurgeryUniversity Hospital of Lausanne (CHUV)University of Lausanne (UNIL)Lausanne1015Switzerland
| | - Fabien B. Wagner
- Defitech Center for Interventional Neurotherapies (NeuroRestore)Department of NeurosurgeryUniversity Hospital of Lausanne (CHUV)University of Lausanne (UNIL)Lausanne1015Switzerland
- UPCourtineCenter for Neuroprosthetics and Brain Mind InstituteSchool of Life SciencesEcole Polytechnique Fédérale de Lausanne (EPFL)Geneva1202Switzerland
- Present address:
Institut des Maladies Neurodégénératives – CNRS UMR 5293Université de BordeauxCentre Broca Nouvelle‐Aquitaine146 rue Léo Saignat – CS 61292 – Case 28, Bordeaux cedexBordeaux33076France
| | - Nicolas Vachicouras
- Bertarelli Foundation Chair in Neuroprosthetic TechnologyLaboratory for Soft Bioelectronic InterfacesInstitute of MicroengineeringInstitute of BioengineeringCenter for NeuroprostheticsEcole Polytechnique Fédérale de Lausanne (EPFL)Geneva1202Switzerland
| | - Ludovic Serex
- Bertarelli Foundation Chair in Neuroprosthetic TechnologyLaboratory for Soft Bioelectronic InterfacesInstitute of MicroengineeringInstitute of BioengineeringCenter for NeuroprostheticsEcole Polytechnique Fédérale de Lausanne (EPFL)Geneva1202Switzerland
| | - Gregory Zegarek
- Department of NeurosurgeryHôpital Universitaire de Genève (HUG)Geneva1205Switzerland
| | - Adrien May
- Department of NeurosurgeryHôpital Universitaire de Genève (HUG)Geneva1205Switzerland
| | - Paul Constanthin
- Department of NeurosurgeryHôpital Universitaire de Genève (HUG)Geneva1205Switzerland
| | - Marie Palma
- BrainTech LaboratoryInsermUniv Grenoble AlpesGrenoble38400France
| | | | - Dirk Van Roost
- Department of NeurosurgeryHôpital Universitaire de Genève (HUG)Geneva1205Switzerland
- Department of NeurosurgeryGhent UniversityGhent9000Belgium
| | - Blaise Yvert
- BrainTech LaboratoryInsermUniv Grenoble AlpesGrenoble38400France
| | - Grégoire Courtine
- Defitech Center for Interventional Neurotherapies (NeuroRestore)Department of NeurosurgeryUniversity Hospital of Lausanne (CHUV)University of Lausanne (UNIL)Lausanne1015Switzerland
- UPCourtineCenter for Neuroprosthetics and Brain Mind InstituteSchool of Life SciencesEcole Polytechnique Fédérale de Lausanne (EPFL)Geneva1202Switzerland
| | - Karl Schaller
- Department of NeurosurgeryHôpital Universitaire de Genève (HUG)Geneva1205Switzerland
| | - Jocelyne Bloch
- Department of NeurosurgeryUniversity Hospital of Lausanne (CHUV) and University of Lausanne (UNIL)Lausanne1010Switzerland
- Defitech Center for Interventional Neurotherapies (NeuroRestore)Department of NeurosurgeryUniversity Hospital of Lausanne (CHUV)University of Lausanne (UNIL)Lausanne1015Switzerland
| | - Stéphanie P. Lacour
- Bertarelli Foundation Chair in Neuroprosthetic TechnologyLaboratory for Soft Bioelectronic InterfacesInstitute of MicroengineeringInstitute of BioengineeringCenter for NeuroprostheticsEcole Polytechnique Fédérale de Lausanne (EPFL)Geneva1202Switzerland
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8
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Koyano KW, Jones AP, McMahon DBT, Waidmann EN, Russ BE, Leopold DA. Dynamic Suppression of Average Facial Structure Shapes Neural Tuning in Three Macaque Face Patches. Curr Biol 2021; 31:1-12.e5. [PMID: 33065012 PMCID: PMC7855058 DOI: 10.1016/j.cub.2020.09.070] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2020] [Revised: 08/14/2020] [Accepted: 09/22/2020] [Indexed: 11/29/2022]
Abstract
The visual perception of identity in humans and other primates is thought to draw upon cortical areas specialized for the analysis of facial structure. A prominent theory of face recognition holds that the brain computes and stores average facial structure, which it then uses to efficiently determine individual identity, though the neural mechanisms underlying this process are controversial. Here, we demonstrate that the dynamic suppression of average facial structure plays a prominent role in the responses of neurons in three fMRI-defined face patches of the macaque. Using photorealistic face stimuli that systematically varied in identity level according to a psychophysically based face space, we found that single units in the AF, AM, and ML face patches exhibited robust tuning around average facial structure. This tuning emerged after the initial excitatory response to the face and was expressed as the selective suppression of sustained responses to low-identity faces. The coincidence of this suppression with increased spike timing synchrony across the population suggests a mechanism of active inhibition underlying this effect. Control experiments confirmed that the diminished responses to low-identity faces were not due to short-term adaptation processes. We propose that the brain's neural suppression of average facial structure facilitates recognition by promoting the extraction of distinctive facial characteristics and suppressing redundant or irrelevant responses across the population.
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Affiliation(s)
- Kenji W Koyano
- Section on Cognitive Neurophysiology and Imaging, National Institute of Mental Health, 49 Convent Dr., Bethesda, MD 20892, USA.
| | - Adam P Jones
- Section on Cognitive Neurophysiology and Imaging, National Institute of Mental Health, 49 Convent Dr., Bethesda, MD 20892, USA
| | - David B T McMahon
- Section on Cognitive Neurophysiology and Imaging, National Institute of Mental Health, 49 Convent Dr., Bethesda, MD 20892, USA; Neuronal Networks Section, National Eye Institute, 49 Convent Dr., Bethesda, MD 20892, USA
| | - Elena N Waidmann
- Section on Cognitive Neurophysiology and Imaging, National Institute of Mental Health, 49 Convent Dr., Bethesda, MD 20892, USA
| | - Brian E Russ
- Section on Cognitive Neurophysiology and Imaging, National Institute of Mental Health, 49 Convent Dr., Bethesda, MD 20892, USA; Center for Biomedical Imaging and Neuromodulation, Nathan S. Kline Institute for Psychiatric Research, 140 Old Orangeburg Road, Orangeburg, NY 10962, USA
| | - David A Leopold
- Section on Cognitive Neurophysiology and Imaging, National Institute of Mental Health, 49 Convent Dr., Bethesda, MD 20892, USA; Neurophysiology Imaging Facility, National Institute of Mental Health, National Institute of Neurological Disorders and Stroke, National Eye Institute, 49 Convent Dr., Bethesda, MD 20892, USA.
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9
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Abstract
Measurements on physical systems result from the systems' activity being converted into sensor measurements by a forward model. In a number of cases, inversion of the forward model is extremely sensitive to perturbations such as sensor noise or numerical errors in the forward model. Regularization is then required, which introduces bias in the reconstruction of the systems' activity. One domain in which this is particularly problematic is the reconstruction of interactions in spatially-extended complex systems such as the human brain. Brain interactions can be reconstructed from non-invasive measurements such as electroencephalography (EEG) or magnetoencephalography (MEG), whose forward models are linear and instantaneous, but have large null-spaces and high condition numbers. This leads to incomplete unmixing of the forward models and hence to spurious interactions. This motivated the development of interaction measures that are exclusively sensitive to lagged, i.e. delayed interactions. The drawback of such measures is that they only detect interactions that have sufficiently large lags and this introduces bias in reconstructed brain networks. We introduce three estimators for linear interactions in spatially-extended systems that are uniformly sensitive to all lags. We derive some basic properties of and relationships between the estimators and evaluate their performance using numerical simulations from a simple benchmark model.
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Affiliation(s)
- Rikkert Hindriks
- Department of Mathematics, VU University Amsterdam, Amsterdam, The Netherlands
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10
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Unruh-Pinheiro A, Hill MR, Weber B, Boström J, Elger CE, Mormann F. Single-Neuron Correlates of Decision Confidence in the Human Medial Temporal Lobe. Curr Biol 2020; 30:4722-4732.e5. [PMID: 33035483 DOI: 10.1016/j.cub.2020.09.021] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Revised: 07/17/2020] [Accepted: 09/07/2020] [Indexed: 12/26/2022]
Abstract
The human medial temporal lobe (MTL) has been suggested to play a role in valuation. However, little is known about its role in binary decisions and metacognition. We performed two decision-making tasks while recording from neurons in the human MTL. During a break, subjects consumed their preferred food item to satiation and subsequently repeated both tasks. We identified both a persistent and a transient modulation of the neural activity. Two independent subpopulations of neurons showed a persistent correlation of their firing rates with either decision confidence or reaction times. Importantly, the changes in confidence and reaction time between experimental sets were accompanied by a correlated change in the neural activity, and this correlation lasted as long as it was relevant for the behavioral task. Previous studies have suggested a transient modulation of the neural activity in the human MTL correlated with subjective value. However, in our study, neither subjective value nor unsigned value could explain this transient activity better than the nutritional features of the stimuli, calling into question the role of the human MTL in valuation.
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Affiliation(s)
- Alexander Unruh-Pinheiro
- Department of Epileptology, University of Bonn Medical Center, Venusberg-Campus 1, 53127 Bonn, Germany
| | - Michael R Hill
- Department of Epileptology, University of Bonn Medical Center, Venusberg-Campus 1, 53127 Bonn, Germany
| | - Bernd Weber
- Department of Epileptology, University of Bonn Medical Center, Venusberg-Campus 1, 53127 Bonn, Germany; Center for Economics and Neuroscience, University of Bonn, Venusberg-Campus 1, 53127 Bonn, Germany
| | - Jan Boström
- Department of Neurosurgery, University of Bonn Medical Center, Venusberg-Campus 1, 53127 Bonn, Germany
| | - Christian E Elger
- Department of Epileptology, University of Bonn Medical Center, Venusberg-Campus 1, 53127 Bonn, Germany
| | - Florian Mormann
- Department of Epileptology, University of Bonn Medical Center, Venusberg-Campus 1, 53127 Bonn, Germany.
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11
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Zhou J, Cheng S, Yang H, Lan L, Chen Y, Xu G, Yin Z, Li Z, Liu M. The brain structure and function alterations in tension-type headache: A protocol for systematic review and meta analysis. Medicine (Baltimore) 2020; 99:e20411. [PMID: 32541463 PMCID: PMC7302660 DOI: 10.1097/md.0000000000020411] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/22/2020] [Accepted: 04/24/2020] [Indexed: 11/26/2022] Open
Abstract
OBJECTIVE The aim of this systematic review and meta-analysis is to improve the understanding of the pathophysiology of tension-type headache (TTH), as well as propose avenues for future neuroimaging studies of TTH. METHODS From the inception dates to May 1, 2020, a systematic literature will search in Medline (Ovid SP), Embase (Ovid SP), Cochrane Central Register of Controlled Trials, Web of Science, and 4 Chinese databases without limitation on language or publication. Additionally, International Clinical Trials Registry Platform , reference lists, and relevant gray literatures will be searched. After screening of eligible references, included studies will be determined according to included criteria, and then data extraction and a methodological quality assessment with a customized checklist will be conducted. Each process will be independently implemented by 2 reviewers, any disagreement will be resolved by consensus to the third researcher. If the extracted data is feasible, anisotropic effect-size version of signed differential mapping will be conducted to perform the meta-analysis of the structural and functional brain alterations in TTH patients.
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Affiliation(s)
- Jun Zhou
- The Acupuncture and Tuina College, the 3rd Teaching Hospital, Chengdu University of Traditional Chinese Medicine, Chengdu, Sichuan
| | - Shirui Cheng
- The Acupuncture and Tuina College, the 3rd Teaching Hospital, Chengdu University of Traditional Chinese Medicine, Chengdu, Sichuan
| | - Han Yang
- The Acupuncture and Tuina College, the 3rd Teaching Hospital, Chengdu University of Traditional Chinese Medicine, Chengdu, Sichuan
| | - Lei Lan
- The Acupuncture and Tuina College, the 3rd Teaching Hospital, Chengdu University of Traditional Chinese Medicine, Chengdu, Sichuan
| | - Yijia Chen
- The School of Basic Medicine of Air Force Medical University, Xi’an
| | - Guixing Xu
- The Acupuncture and Tuina College, the 3rd Teaching Hospital, Chengdu University of Traditional Chinese Medicine, Chengdu, Sichuan
| | - Zihan Yin
- The Acupuncture and Tuina College, the 3rd Teaching Hospital, Chengdu University of Traditional Chinese Medicine, Chengdu, Sichuan
| | - Zhengjie Li
- The Acupuncture and Tuina College, the 3rd Teaching Hospital, Chengdu University of Traditional Chinese Medicine, Chengdu, Sichuan
- Acupuncture-Brain Research Center, Chengdu University of Traditional Chinese Medicine, Chengdu, Sichuan, China
| | - Mailan Liu
- College of Acupuncture & Moxibustion and Tuina, Hunan University of Chinese Medicine, Hunan
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12
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Pfeiffer C, Ruffieux S, Andersen LM, Kalabukhov A, Winkler D, Oostenveld R, Lundqvist D, Schneiderman JF. On-scalp MEG sensor localization using magnetic dipole-like coils: A method for highly accurate co-registration. Neuroimage 2020; 212:116686. [PMID: 32119981 DOI: 10.1016/j.neuroimage.2020.116686] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2019] [Revised: 02/13/2020] [Accepted: 02/24/2020] [Indexed: 11/17/2022] Open
Abstract
Source modelling in magnetoencephalography (MEG) requires precise co-registration of the sensor array and the anatomical structure of the measured individual's head. In conventional MEG, the positions and orientations of the sensors relative to each other are fixed and known beforehand, requiring only localization of the head relative to the sensor array. Since the sensors in on-scalp MEG are positioned on the scalp, locations of the individual sensors depend on the subject's head shape and size. The positions and orientations of on-scalp sensors must therefore be measured at every recording. This can be achieved by inverting conventional head localization, localizing the sensors relative to the head - rather than the other way around. In this study we present a practical method for localizing sensors using magnetic dipole-like coils attached to the subject's head. We implement and evaluate the method in a set of on-scalp MEG recordings using a 7-channel on-scalp MEG system based on high critical temperature superconducting quantum interference devices (high-Tc SQUIDs). The method allows individually localizing the sensor positions, orientations, and responsivities with high accuracy using only a short averaging time (≤ 2 mm, < 3° and < 3%, respectively, with 1-s averaging), enabling continuous sensor localization. Calibrating and jointly localizing the sensor array can further improve the accuracy of position and orientation (< 1 mm and < 1°, respectively, with 1-s coil recordings). We demonstrate source localization of on-scalp recorded somatosensory evoked activity based on co-registration with our method. Equivalent current dipole fits of the evoked responses corresponded well (within 4.2 mm) with those based on a commercial, whole-head MEG system.
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Affiliation(s)
- Christoph Pfeiffer
- Department of Microtechnology and Nanoscience - MC2, Chalmers University of Technology, Gothenburg, Sweden.
| | - Silvia Ruffieux
- Department of Microtechnology and Nanoscience - MC2, Chalmers University of Technology, Gothenburg, Sweden
| | - Lau M Andersen
- NatMEG, Department of Clinical Neuroscience, The Karolinska Institute, Stockholm, Sweden
| | - Alexei Kalabukhov
- Department of Microtechnology and Nanoscience - MC2, Chalmers University of Technology, Gothenburg, Sweden
| | - Dag Winkler
- Department of Microtechnology and Nanoscience - MC2, Chalmers University of Technology, Gothenburg, Sweden
| | - Robert Oostenveld
- Donders Institute for Brain, Cognition and Behaviour, Radboud University, Nijmegen, Netherlands
| | - Daniel Lundqvist
- NatMEG, Department of Clinical Neuroscience, The Karolinska Institute, Stockholm, Sweden
| | - Justin F Schneiderman
- MedTech West and the Insitute of Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
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13
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Borna A, Carter TR, Colombo AP, Jau YY, McKay J, Weisend M, Taulu S, Stephen JM, Schwindt PDD. Non-Invasive Functional-Brain-Imaging with an OPM-based Magnetoencephalography System. PLoS One 2020; 15:e0227684. [PMID: 31978102 PMCID: PMC6980641 DOI: 10.1371/journal.pone.0227684] [Citation(s) in RCA: 57] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2019] [Accepted: 12/25/2019] [Indexed: 12/14/2022] Open
Abstract
A non-invasive functional-brain-imaging system based on optically-pumped-magnetometers (OPM) is presented. The OPM-based magnetoencephalography (MEG) system features 20 OPM channels conforming to the subject's scalp. We have conducted two MEG experiments on three subjects: assessment of somatosensory evoked magnetic field (SEF) and auditory evoked magnetic field (AEF) using our OPM-based MEG system and a commercial MEG system based on superconducting quantum interference devices (SQUIDs). We cross validated the robustness of our system by calculating the distance between the location of the equivalent current dipole (ECD) yielded by our OPM-based MEG system and the ECD location calculated by the commercial SQUID-based MEG system. We achieved sub-centimeter accuracy for both SEF and AEF responses in all three subjects. Due to the proximity (12 mm) of the OPM channels to the scalp, it is anticipated that future OPM-based MEG systems will offer enhanced spatial resolution as they will capture finer spatial features compared to traditional MEG systems employing SQUIDs.
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Affiliation(s)
- Amir Borna
- Sandia National Laboratories, Albuquerque, NM, United States of America
- * E-mail:
| | - Tony R. Carter
- Sandia National Laboratories, Albuquerque, NM, United States of America
| | | | - Yuan-Yu Jau
- Sandia National Laboratories, Albuquerque, NM, United States of America
| | - Jim McKay
- Candoo Systems Inc., Coquitlam, BC, Canada
| | | | - Samu Taulu
- University of Washington Seattle, Seattle, WA, United States of America
| | - Julia M. Stephen
- The Mind Research Network and Lovelace Biomedical and Environmental Research Institute, Albuquerque, NM, United States of America
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14
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Dodani SS, Lu CW, Aldridge JW, Chou KL, Patil PG. A Computerized Microelectrode Recording to Magnetic Resonance Imaging Mapping System for Subthalamic Nucleus Deep Brain Stimulation Surgery. Oper Neurosurg (Hagerstown) 2019; 14:661-667. [PMID: 28961898 DOI: 10.1093/ons/opx169] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2016] [Accepted: 07/11/2017] [Indexed: 11/15/2022] Open
Abstract
BACKGROUND Accurate electrode placement is critical to the success of deep brain stimulation (DBS) surgery. Suboptimal targeting may arise from poor initial target localization, frame-based targeting error, or intraoperative brain shift. These uncertainties can make DBS surgery challenging. OBJECTIVE To develop a computerized system to guide subthalamic nucleus (STN) DBS electrode localization and to estimate the trajectory of intraoperative microelectrode recording (MER) on magnetic resonance (MR) images algorithmically during DBS surgery. METHODS Our method is based upon the relationship between the high-frequency band (HFB; 500-2000 Hz) signal from MER and voxel intensity on MR images. The HFB profile along an MER trajectory recorded during surgery is compared to voxel intensity profiles along many potential trajectories in the region of the surgically planned trajectory. From these comparisons of HFB recordings and potential trajectories, an estimate of the MER trajectory is calculated. This calculated trajectory is then compared to actual trajectory, as estimated by postoperative high-resolution computed tomography. RESULTS We compared 20 planned, calculated, and actual trajectories in 13 patients who underwent STN DBS surgery. Targeting errors for our calculated trajectories (2.33 mm ± 0.2 mm) were significantly less than errors for surgically planned trajectories (2.83 mm ± 0.2 mm; P = .01), improving targeting prediction in 70% of individual cases (14/20). Moreover, in 4 of 4 initial MER trajectories that missed the STN, our method correctly indicated the required direction of targeting adjustment for the DBS lead to intersect the STN. CONCLUSION A computer-based algorithm simultaneously utilizing MER and MR information potentially eases electrode localization during STN DBS surgery.
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Affiliation(s)
- Sunjay S Dodani
- Surgical Therapies Improving Movement Program, University of Michigan, Ann Arbor, Michigan
- Department of Neurosurgery, University of Michigan, Ann Arbor, Michigan
- Department of Neurology, University of Michigan, Ann Arbor, Michigan
| | - Charles W Lu
- Surgical Therapies Improving Movement Program, University of Michigan, Ann Arbor, Michigan
- Department of Neurosurgery, University of Michigan, Ann Arbor, Michigan
- Department of Neurology, University of Michigan, Ann Arbor, Michigan
| | - J Wayne Aldridge
- Surgical Therapies Improving Movement Program, University of Michigan, Ann Arbor, Michigan
- Department of Neurosurgery, University of Michigan, Ann Arbor, Michigan
- Department of Psychology, University of Michigan, Ann Arbor, Michigan
| | - Kelvin L Chou
- Surgical Therapies Improving Movement Program, University of Michigan, Ann Arbor, Michigan
- Department of Neurosurgery, University of Michigan, Ann Arbor, Michigan
- Department of Neurology, University of Michigan, Ann Arbor, Michigan
| | - Parag G Patil
- Surgical Therapies Improving Movement Program, University of Michigan, Ann Arbor, Michigan
- Department of Neurosurgery, University of Michigan, Ann Arbor, Michigan
- Department of Neurology, University of Michigan, Ann Arbor, Michigan
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, Michigan
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15
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Abstract
PURPOSE Ultra-high field magnetic resonance imaging poses a number of challenges for robust radio frequency coil designs. A monopole antenna array can potentially overcome key limitations of birdcage coil designs and may provide a useful radio frequency coil for brain imaging. METHODS Four, 8 and 12 element monopole antenna arrays were simulated using 3 T and 7T magnetic resonance imaging frequencies. For comparison, 4, 8 and 12 element birdcage coils were also simulated. Coil performance was evaluated and compared and the impact of shielding was assessed. A 4 element monopole antenna array was fabricated and bench tested. RESULTS Comparison of the 4, 8 and 12 element designs suggest that the monopole antenna array leads to better field properties than the birdcage coil in all configurations studied: unloaded, loaded with saline and loaded using a head phantom. Improvements in field properties and homogeneity were evident at both field strengths, implying that the monopole antenna array has potential for head imaging. The monopole antenna array also appears to be more efficient than the comparable birdcage coil design. Additionally, the former is scalable via the addition of more elements whereas our results suggest that this is not the case for the latter. Bench testing results show that the monopole antenna array is well matched with the transmission line, and mutual coupling between elements is sufficiently low. CONCLUSION We found the monopole antenna array generated a larger field intensity than the birdcage coil design, whilst also producing a more useful magnetic resonance imaging field as measured by radio frequency field homogeneity. Our study suggests that magnetic resonance imaging of the brain can likely benefit from the use of radio frequency monopole antenna arrays.
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Affiliation(s)
- A. S. M. Zahid Kausar
- Centre for Advanced Imaging, University of Queensland, St Lucia, Brisbane, Australia
| | - David C. Reutens
- Centre for Advanced Imaging, University of Queensland, St Lucia, Brisbane, Australia
| | - Ewald Weber
- School of Information Technology and Electrical Engineering, University of Queensland, St Lucia, Brisbane, Australia
| | - Viktor Vegh
- Centre for Advanced Imaging, University of Queensland, St Lucia, Brisbane, Australia
- * E-mail:
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16
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Masvidal-Codina E, Illa X, Dasilva M, Calia AB, Dragojević T, Vidal-Rosas EE, Prats-Alfonso E, Martínez-Aguilar J, De la Cruz JM, Garcia-Cortadella R, Godignon P, Rius G, Camassa A, Del Corro E, Bousquet J, Hébert C, Durduran T, Villa R, Sanchez-Vives MV, Garrido JA, Guimerà-Brunet A. High-resolution mapping of infraslow cortical brain activity enabled by graphene microtransistors. Nat Mater 2019; 18:280-288. [PMID: 30598536 DOI: 10.1038/s41563-018-0249-4] [Citation(s) in RCA: 74] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/21/2018] [Accepted: 11/14/2018] [Indexed: 05/24/2023]
Abstract
Recording infraslow brain signals (<0.1 Hz) with microelectrodes is severely hampered by current microelectrode materials, primarily due to limitations resulting from voltage drift and high electrode impedance. Hence, most recording systems include high-pass filters that solve saturation issues but come hand in hand with loss of physiological and pathological information. In this work, we use flexible epicortical and intracortical arrays of graphene solution-gated field-effect transistors (gSGFETs) to map cortical spreading depression in rats and demonstrate that gSGFETs are able to record, with high fidelity, infraslow signals together with signals in the typical local field potential bandwidth. The wide recording bandwidth results from the direct field-effect coupling of the active transistor, in contrast to standard passive electrodes, as well as from the electrochemical inertness of graphene. Taking advantage of such functionality, we envision broad applications of gSGFET technology for monitoring infraslow brain activity both in research and in the clinic.
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Affiliation(s)
- Eduard Masvidal-Codina
- Institut de Microelectrònica de Barcelona, IMB-CNM (CSIC), Esfera UAB, Bellaterra, Spain
| | - Xavi Illa
- Institut de Microelectrònica de Barcelona, IMB-CNM (CSIC), Esfera UAB, Bellaterra, Spain
- Centro de Investigación Biomédica en Red en Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN), Madrid, Spain
| | - Miguel Dasilva
- Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain
| | - Andrea Bonaccini Calia
- Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and The Barcelona Institute of Science and Technology (BIST), Campus UAB, Bellaterra, Barcelona, Spain
| | - Tanja Dragojević
- ICFO-Institut de Ciéncies Fotòniques, The Barcelona Institute of Science and Technology, Castelldefels, Barcelona, Spain
| | - Ernesto E Vidal-Rosas
- ICFO-Institut de Ciéncies Fotòniques, The Barcelona Institute of Science and Technology, Castelldefels, Barcelona, Spain
| | - Elisabet Prats-Alfonso
- Institut de Microelectrònica de Barcelona, IMB-CNM (CSIC), Esfera UAB, Bellaterra, Spain
- Centro de Investigación Biomédica en Red en Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN), Madrid, Spain
| | - Javier Martínez-Aguilar
- Institut de Microelectrònica de Barcelona, IMB-CNM (CSIC), Esfera UAB, Bellaterra, Spain
- Centro de Investigación Biomédica en Red en Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN), Madrid, Spain
| | - Jose M De la Cruz
- Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and The Barcelona Institute of Science and Technology (BIST), Campus UAB, Bellaterra, Barcelona, Spain
| | - Ramon Garcia-Cortadella
- Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and The Barcelona Institute of Science and Technology (BIST), Campus UAB, Bellaterra, Barcelona, Spain
| | - Philippe Godignon
- Institut de Microelectrònica de Barcelona, IMB-CNM (CSIC), Esfera UAB, Bellaterra, Spain
| | - Gemma Rius
- Institut de Microelectrònica de Barcelona, IMB-CNM (CSIC), Esfera UAB, Bellaterra, Spain
| | - Alessandra Camassa
- Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain
| | - Elena Del Corro
- Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and The Barcelona Institute of Science and Technology (BIST), Campus UAB, Bellaterra, Barcelona, Spain
| | - Jessica Bousquet
- Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and The Barcelona Institute of Science and Technology (BIST), Campus UAB, Bellaterra, Barcelona, Spain
| | - Clement Hébert
- Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and The Barcelona Institute of Science and Technology (BIST), Campus UAB, Bellaterra, Barcelona, Spain
| | - Turgut Durduran
- ICFO-Institut de Ciéncies Fotòniques, The Barcelona Institute of Science and Technology, Castelldefels, Barcelona, Spain
- Institució Catalana de Recerca i Estudis Avançats (ICREA), Barcelona, Spain
| | - Rosa Villa
- Institut de Microelectrònica de Barcelona, IMB-CNM (CSIC), Esfera UAB, Bellaterra, Spain
- Centro de Investigación Biomédica en Red en Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN), Madrid, Spain
| | - Maria V Sanchez-Vives
- Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain
- Institució Catalana de Recerca i Estudis Avançats (ICREA), Barcelona, Spain
| | - Jose A Garrido
- Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and The Barcelona Institute of Science and Technology (BIST), Campus UAB, Bellaterra, Barcelona, Spain.
- Institució Catalana de Recerca i Estudis Avançats (ICREA), Barcelona, Spain.
| | - Anton Guimerà-Brunet
- Institut de Microelectrònica de Barcelona, IMB-CNM (CSIC), Esfera UAB, Bellaterra, Spain.
- Centro de Investigación Biomédica en Red en Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN), Madrid, Spain.
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Lancia S, Choi J, Baek J, Mammarella S, Bianco D, Quaresima V, Ferrari M. Trail Making Test Induces Prefrontal Cortex Activation as Revealed by a cw Wearable-Wireless fNIRS/DOT Imager. Adv Exp Med Biol 2019; 1072:139-144. [PMID: 30178336 DOI: 10.1007/978-3-319-91287-5_22] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The recent availability of low-cost wearable continuous wave (cw) fNIRS/DOT devices is supposed to revolutionize cortical human brain mapping in the real-life. Ecological paper-pencil tests, as the Trail Making Test (TMT), are commonly used in neuropsychological clinics but its neural substrates are not completely understood. The aim of this study was to map, using a new cw wearable fNIRS/DOT imager (NIRSIT), the prefrontal cortex (PFC) hemodynamic response in healthy subjects while performing the TMT. The ANOVA analysis, performed on the 60 region-DOT data, shows a significant task-related activation of the PFC. These preliminary results support the validity of this wearable technology to provide online high-density PFC activation maps.
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Affiliation(s)
- Stefania Lancia
- Department of Life, Health and Environmental Sciences, University of L'Aquila, L'Aquila, Italy
| | | | | | - Silvia Mammarella
- Department of Life, Health and Environmental Sciences, University of L'Aquila, L'Aquila, Italy
| | - Denise Bianco
- Department of Life, Health and Environmental Sciences, University of L'Aquila, L'Aquila, Italy
| | - Valentina Quaresima
- Department of Life, Health and Environmental Sciences, University of L'Aquila, L'Aquila, Italy
| | - Marco Ferrari
- Department of Life, Health and Environmental Sciences, University of L'Aquila, L'Aquila, Italy.
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18
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Mugler EM, Tate MC, Livescu K, Templer JW, Goldrick MA, Slutzky MW. Differential Representation of Articulatory Gestures and Phonemes in Precentral and Inferior Frontal Gyri. J Neurosci 2018; 38:9803-9813. [PMID: 30257858 PMCID: PMC6234299 DOI: 10.1523/jneurosci.1206-18.2018] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2018] [Revised: 09/09/2018] [Accepted: 09/10/2018] [Indexed: 11/21/2022] Open
Abstract
Speech is a critical form of human communication and is central to our daily lives. Yet, despite decades of study, an understanding of the fundamental neural control of speech production remains incomplete. Current theories model speech production as a hierarchy from sentences and phrases down to words, syllables, speech sounds (phonemes), and the actions of vocal tract articulators used to produce speech sounds (articulatory gestures). Here, we investigate the cortical representation of articulatory gestures and phonemes in ventral precentral and inferior frontal gyri in men and women. Our results indicate that ventral precentral cortex represents gestures to a greater extent than phonemes, while inferior frontal cortex represents both gestures and phonemes. These findings suggest that speech production shares a common cortical representation with that of other types of movement, such as arm and hand movements. This has important implications both for our understanding of speech production and for the design of brain-machine interfaces to restore communication to people who cannot speak.SIGNIFICANCE STATEMENT Despite being studied for decades, the production of speech by the brain is not fully understood. In particular, the most elemental parts of speech, speech sounds (phonemes) and the movements of vocal tract articulators used to produce these sounds (articulatory gestures), have both been hypothesized to be encoded in motor cortex. Using direct cortical recordings, we found evidence that primary motor and premotor cortices represent gestures to a greater extent than phonemes. Inferior frontal cortex (part of Broca's area) appears to represent both gestures and phonemes. These findings suggest that speech production shares a similar cortical organizational structure with the movement of other body parts.
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Affiliation(s)
| | | | - Karen Livescu
- Toyota Technological Institute at Chicago, Chicago, Illinois 60637
| | | | | | - Marc W Slutzky
- Departments of Neurology,
- Physiology
- Physical Medicine & Rehabilitation, Northwestern University, Chicago, Illinois 60611, and
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19
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Zinkus TP. Pre-Surgical Planning: Multimodality Imaging to Optimize Outcomes in Pediatric Epilepsy Surgery. Mo Med 2018; 115:365-367. [PMID: 30228769 PMCID: PMC6140251] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Neuroimaging is an important component of the pre-surgical planning for pediatric epilepsy. High-resolution structural magnetic resonance images are combined with advanced structural and functional imaging techniques to better define the surgical lesion and decrease morbidity postoperatively. The combination of neuroimaging, electroencephalography (EEG), and neuropsychiatric testing in a multidisciplinary epilepsy conference setting is essential for determining a plan for surgical management.
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Affiliation(s)
- Timothy P Zinkus
- Timothy P. Zinkus, MD, is Assistant Professor, Pediatric Radiology, Children's Mercy, University of Missouri, Kansas City, Kansas City, Mo
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20
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Degenhart AD, Hiremath SV, Yang Y, Foldes S, Collinger JL, Boninger M, Tyler-Kabara EC, Wang W. Remapping cortical modulation for electrocorticographic brain-computer interfaces: a somatotopy-based approach in individuals with upper-limb paralysis. J Neural Eng 2018; 15:026021. [PMID: 29160240 PMCID: PMC5841472 DOI: 10.1088/1741-2552/aa9bfb] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
OBJECTIVE Brain-computer interface (BCI) technology aims to provide individuals with paralysis a means to restore function. Electrocorticography (ECoG) uses disc electrodes placed on either the surface of the dura or the cortex to record field potential activity. ECoG has been proposed as a viable neural recording modality for BCI systems, potentially providing stable, long-term recordings of cortical activity with high spatial and temporal resolution. Previously we have demonstrated that a subject with spinal cord injury (SCI) could control an ECoG-based BCI system with up to three degrees of freedom (Wang et al 2013 PLoS One). Here, we expand upon these findings by including brain-control results from two additional subjects with upper-limb paralysis due to amyotrophic lateral sclerosis and brachial plexus injury, and investigate the potential of motor and somatosensory cortical areas to enable BCI control. APPROACH Individuals were implanted with high-density ECoG electrode grids over sensorimotor cortical areas for less than 30 d. Subjects were trained to control a BCI by employing a somatotopic control strategy where high-gamma activity from attempted arm and hand movements drove the velocity of a cursor. MAIN RESULTS Participants were capable of generating robust cortical modulation that was differentiable across attempted arm and hand movements of their paralyzed limb. Furthermore, all subjects were capable of voluntarily modulating this activity to control movement of a computer cursor with up to three degrees of freedom using the somatotopic control strategy. Additionally, for those subjects with electrode coverage of somatosensory cortex, we found that somatosensory cortex was capable of supporting ECoG-based BCI control. SIGNIFICANCE These results demonstrate the feasibility of ECoG-based BCI systems for individuals with paralysis as well as highlight some of the key challenges that must be overcome before such systems are translated to the clinical realm. ClinicalTrials.gov Identifier: NCT01393444.
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Affiliation(s)
- Alan D. Degenhart
- Systems Neuroscience Institute, University of Pittsburgh, PA, USA
- Center for the Neural Basis of Cognition, Pittsburgh, PA, USA
| | - Shivayogi V. Hiremath
- Department of Physical Medicine and Rehabilitation, University of Pittsburgh, Pittsburgh, PA, USA
- Department of Physical Therapy, Temple University, Philadelphia, PA, USA
| | - Ying Yang
- Department of Physical Medicine and Rehabilitation, University of Pittsburgh, Pittsburgh, PA, USA
| | - Stephen Foldes
- Center for the Neural Basis of Cognition, Pittsburgh, PA, USA
- Department of Physical Medicine and Rehabilitation, University of Pittsburgh, Pittsburgh, PA, USA
- Department of Veterans Affairs Medical Center, Pittsburgh, PA, USA
| | - Jennifer L. Collinger
- Center for the Neural Basis of Cognition, Pittsburgh, PA, USA
- Department of Physical Medicine and Rehabilitation, University of Pittsburgh, Pittsburgh, PA, USA
- Department of Veterans Affairs Medical Center, Pittsburgh, PA, USA
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA, USA
| | - Michael Boninger
- Department of Physical Medicine and Rehabilitation, University of Pittsburgh, Pittsburgh, PA, USA
- Department of Veterans Affairs Medical Center, Pittsburgh, PA, USA
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA, USA
- McGowan Institute for Regenerative Medicine, Pittsburgh, PA, USA
- Clinical and Translational Science Institute, Pittsburgh, PA, USA
| | - Elizabeth C. Tyler-Kabara
- Department of Physical Medicine and Rehabilitation, University of Pittsburgh, Pittsburgh, PA, USA
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA, USA
- Department of Neurological Surgery, University of Pittsburgh, Pittsburgh, PA, USA
| | - Wei Wang
- Department of Physical Medicine and Rehabilitation, University of Pittsburgh, Pittsburgh, PA, USA
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA, USA
- Clinical and Translational Science Institute, Pittsburgh, PA, USA
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO, USA
- Barnes-Jewish Hospital, St. Louis, MO, USA
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Luan L, Sullender CT, Li X, Zhao Z, Zhu H, Wei X, Xie C, Dunn AK. Nanoelectronics enabled chronic multimodal neural platform in a mouse ischemic model. J Neurosci Methods 2018; 295:68-76. [PMID: 29203409 PMCID: PMC5801157 DOI: 10.1016/j.jneumeth.2017.12.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2017] [Revised: 11/22/2017] [Accepted: 12/01/2017] [Indexed: 01/22/2023]
Abstract
BACKGROUND Despite significant advancements of optical imaging techniques for mapping hemodynamics in small animal models, it remains challenging to combine imaging with spatially resolved electrical recording of individual neurons especially for longitudinal studies. This is largely due to the strong invasiveness to the living brain from the penetrating electrodes and their limited compatibility with longitudinal imaging. NEW METHOD We implant arrays of ultraflexible nanoelectronic threads (NETs) in mice for neural recording both at the brain surface and intracortically, which maintain great tissue compatibility chronically. By mounting a cranial window atop of the NET arrays that allows for chronic optical access, we establish a multimodal platform that combines spatially resolved electrical recording of neural activity and laser speckle contrast imaging (LSCI) of cerebral blood flow (CBF) for longitudinal studies. RESULTS We induce peri-infarct depolarizations (PIDs) by targeted photothrombosis, and show the ability to detect its occurrence and propagation through spatiotemporal variations in both extracellular potentials and CBF. We also demonstrate chronic tracking of single-unit neural activity and CBF over days after photothrombosis, from which we observe reperfusion and increased firing rates. COMPARISON WITH EXISTING METHOD(S) This multimodal platform enables simultaneous mapping of neural activity and hemodynamic parameters at the microscale for quantitative, longitudinal comparisons with minimal perturbation to the baseline neurophysiology. CONCLUSION The ability to spatiotemporally resolve and chronically track CBF and neural electrical activity in the same living brain region has broad applications for studying the interplay between neural and hemodynamic responses in health and in cerebrovascular and neurological pathologies.
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Affiliation(s)
- Lan Luan
- Department of Biomedical Engineering, The University of Texas at Austin, United States; Department of Physics, The University of Texas at Austin, United States.
| | - Colin T Sullender
- Department of Biomedical Engineering, The University of Texas at Austin, United States
| | - Xue Li
- Department of Biomedical Engineering, The University of Texas at Austin, United States
| | - Zhengtuo Zhao
- Department of Biomedical Engineering, The University of Texas at Austin, United States
| | - Hanlin Zhu
- Department of Biomedical Engineering, The University of Texas at Austin, United States
| | - Xiaoling Wei
- Department of Biomedical Engineering, The University of Texas at Austin, United States
| | - Chong Xie
- Department of Biomedical Engineering, The University of Texas at Austin, United States.
| | - Andrew K Dunn
- Department of Biomedical Engineering, The University of Texas at Austin, United States.
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22
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Shah P, Bassett DS, Wisse LE, Detre JA, Stein JM, Yushkevich PA, Shinohara RT, Pluta JB, Valenciano E, Daffner M, Wolk DA, Elliott MA, Litt B, Davis KA, Das SR. Mapping the structural and functional network architecture of the medial temporal lobe using 7T MRI. Hum Brain Mapp 2018; 39:851-865. [PMID: 29159960 PMCID: PMC5764800 DOI: 10.1002/hbm.23887] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2017] [Revised: 10/31/2017] [Accepted: 11/06/2017] [Indexed: 12/13/2022] Open
Abstract
Medial temporal lobe (MTL) subregions play integral roles in memory function and are differentially affected in various neurological and psychiatric disorders. The ability to structurally and functionally characterize these subregions may be important to understanding MTL physiology and diagnosing diseases involving the MTL. In this study, we characterized network architecture of the MTL in healthy subjects (n = 31) using both resting state functional MRI and MTL-focused T2-weighted structural MRI at 7 tesla. Ten MTL subregions per hemisphere, including hippocampal subfields and cortical regions of the parahippocampal gyrus, were segmented for each subject using a multi-atlas algorithm. Both structural covariance matrices from correlations of subregion volumes across subjects, and functional connectivity matrices from correlations between subregion BOLD time series were generated. We found a moderate structural and strong functional inter-hemispheric symmetry. Several bilateral hippocampal subregions (CA1, dentate gyrus, and subiculum) emerged as functional network hubs. We also observed that the structural and functional networks naturally separated into two modules closely corresponding to (a) bilateral hippocampal formations, and (b) bilateral extra-hippocampal structures. Finally, we found a significant correlation in structural and functional connectivity (r = 0.25). Our findings represent a comprehensive analysis of network topology of the MTL at the subregion level. We share our data, methods, and findings as a reference for imaging methods and disease-based research.
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Affiliation(s)
- Preya Shah
- Department of BioengineeringUniversity of PennsylvaniaPhiladelphiaPennsylvania19104
- Center for Neuroengineering and TherapeuticsUniversity of PennsylvaniaPhiladelphiaPennsylvania19104
| | - Danielle S. Bassett
- Department of BioengineeringUniversity of PennsylvaniaPhiladelphiaPennsylvania19104
- Department of Electrical & Systems EngineeringUniversity of PennsylvaniaPhiladelphiaPennsylvania19104
| | - Laura E.M. Wisse
- Penn Image Computing and Science LaboratoryUniversity of PennsylvaniaPhiladelphiaPennsylvania19104
- Department of RadiologyUniversity of PennsylvaniaPhiladelphiaPennsylvania19104
| | - John A. Detre
- Department of RadiologyUniversity of PennsylvaniaPhiladelphiaPennsylvania19104
- Department of NeurologyUniversity of PennsylvaniaPhiladelphiaPennsylvania19104
- Center for Functional Neuroimaging, University of PennsylvaniaPhiladelphiaPennsylvania19104
| | - Joel M. Stein
- Department of RadiologyUniversity of PennsylvaniaPhiladelphiaPennsylvania19104
| | - Paul A. Yushkevich
- Penn Image Computing and Science LaboratoryUniversity of PennsylvaniaPhiladelphiaPennsylvania19104
- Department of RadiologyUniversity of PennsylvaniaPhiladelphiaPennsylvania19104
| | - Russell T. Shinohara
- Department of BiostatisticsEpidemiology and Informatics, University of PennsylvaniaPhiladelphiaPennsylvania19104
| | - John B. Pluta
- Penn Image Computing and Science LaboratoryUniversity of PennsylvaniaPhiladelphiaPennsylvania19104
- Department of RadiologyUniversity of PennsylvaniaPhiladelphiaPennsylvania19104
| | - Elijah Valenciano
- Penn Image Computing and Science LaboratoryUniversity of PennsylvaniaPhiladelphiaPennsylvania19104
| | - Molly Daffner
- Department of NeurologyUniversity of PennsylvaniaPhiladelphiaPennsylvania19104
- Penn Memory Center, University of PennsylvaniaPhiladelphiaPennsylvania19104
| | - David A. Wolk
- Department of NeurologyUniversity of PennsylvaniaPhiladelphiaPennsylvania19104
- Penn Memory Center, University of PennsylvaniaPhiladelphiaPennsylvania19104
| | - Mark A. Elliott
- Department of RadiologyUniversity of PennsylvaniaPhiladelphiaPennsylvania19104
| | - Brian Litt
- Department of BioengineeringUniversity of PennsylvaniaPhiladelphiaPennsylvania19104
- Center for Neuroengineering and TherapeuticsUniversity of PennsylvaniaPhiladelphiaPennsylvania19104
- Department of NeurologyUniversity of PennsylvaniaPhiladelphiaPennsylvania19104
| | - Kathryn A. Davis
- Center for Neuroengineering and TherapeuticsUniversity of PennsylvaniaPhiladelphiaPennsylvania19104
- Department of NeurologyUniversity of PennsylvaniaPhiladelphiaPennsylvania19104
| | - Sandhitsu R. Das
- Penn Image Computing and Science LaboratoryUniversity of PennsylvaniaPhiladelphiaPennsylvania19104
- Department of NeurologyUniversity of PennsylvaniaPhiladelphiaPennsylvania19104
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Silva MA, See AP, Essayed WI, Golby AJ, Tie Y. Challenges and techniques for presurgical brain mapping with functional MRI. Neuroimage Clin 2017; 17:794-803. [PMID: 29270359 PMCID: PMC5735325 DOI: 10.1016/j.nicl.2017.12.008] [Citation(s) in RCA: 75] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/20/2017] [Revised: 11/10/2017] [Accepted: 12/05/2017] [Indexed: 01/22/2023]
Abstract
Functional magnetic resonance imaging (fMRI) is increasingly used for preoperative counseling and planning, and intraoperative guidance for tumor resection in the eloquent cortex. Although there have been improvements in image resolution and artifact correction, there are still limitations of this modality. In this review, we discuss clinical fMRI's applications, limitations and potential solutions. These limitations depend on the following parameters: foundations of fMRI, physiologic effects of the disease, distinctions between clinical and research fMRI, and the design of the fMRI study. We also compare fMRI to other brain mapping modalities which should be considered as alternatives or adjuncts when appropriate, and discuss intraoperative use and validation of fMRI. These concepts direct the clinical application of fMRI in neurosurgical patients. fMRI is increasingly used for presurgical brain mapping for surgical planning. Understanding of the limitations of fMRI is critical for its clinical use. Clinical fMRI's challenges and potential solutions are discussed. Intraoperative use and validation of fMRI are discussed.
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Affiliation(s)
- Michael A Silva
- Harvard Medical School, Boston, MA, USA; Department of Neurosurgery, Brigham and Women's Hospital, Boston, MA, USA
| | - Alfred P See
- Harvard Medical School, Boston, MA, USA; Department of Neurosurgery, Brigham and Women's Hospital, Boston, MA, USA
| | - Walid I Essayed
- Harvard Medical School, Boston, MA, USA; Department of Neurosurgery, Brigham and Women's Hospital, Boston, MA, USA
| | - Alexandra J Golby
- Harvard Medical School, Boston, MA, USA; Department of Neurosurgery, Brigham and Women's Hospital, Boston, MA, USA; Department of Radiology, Brigham and Women's Hospital, Boston, MA, USA
| | - Yanmei Tie
- Harvard Medical School, Boston, MA, USA; Department of Neurosurgery, Brigham and Women's Hospital, Boston, MA, USA.
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24
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Lin X, Xu S, Ieong HFH, Yuan Z. Optical mapping of prefrontal activity in pathological gamblers. Appl Opt 2017; 56:5948-5953. [PMID: 29047916 DOI: 10.1364/ao.56.005948] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2017] [Accepted: 06/27/2017] [Indexed: 06/07/2023]
Abstract
Functional near-infrared spectroscopy (fNIRS) has emerged as a highly promising brain mapping technique that enables continuously and noninvasively monitoring the hemodynamic responses in the human brain. In this study, fNIRS was utilized to identify the different brain activation patterns between pathological gamblers (PGs) and healthy controls (HCs). Specifically, we examined the hemodynamic changes in the prefrontal cortex using fNIRS recordings during the completion of executive function and decision-making tasks for both PGs and HCs. Our mapping results revealed that PGs and HCs exhibited notable differences in the hemodynamic responses and brain activation patterns across the prefrontal region.
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25
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Navarro de Lara LI, Tik M, Woletz M, Frass-Kriegl R, Moser E, Laistler E, Windischberger C. High-sensitivity TMS/fMRI of the Human Motor Cortex Using a Dedicated Multichannel MR Coil. Neuroimage 2017; 150:262-269. [PMID: 28254457 DOI: 10.1016/j.neuroimage.2017.02.062] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2016] [Revised: 02/03/2017] [Accepted: 02/21/2017] [Indexed: 11/19/2022] Open
Abstract
PURPOSE To validate a novel setup for concurrent TMS/fMRI in the human motor cortex based on a dedicated, ultra-thin, multichannel receive MR coil positioned between scalp and TMS system providing greatly enhanced sensitivity compared to the standard birdcage coil setting. METHODS A combined TMS/fMRI design was applied over the primary motor cortex based on 1Hz stimulation with stimulation levels of 80%, 90%, 100%, and 110% of the individual active motor threshold, respectively. Due to the use of a multichannel receive coil we were able to use multiband-accelerated (MB=2) EPI sequences for the acquisition of functional images. Data were analysed with SPM12 and BOLD-weighted signal intensity time courses were extracted in each subject from two local maxima (individual functional finger tapping localiser, fixed MNI coordinate of the hand knob) next to the hand area of the primary motor cortex (M1) and from the global maximum. RESULTS We report excellent image quality without noticeable signal dropouts or image distortions. Parameter estimates in the three peak voxels showed monotonically ascending activation levels over increasing stimulation intensities. Across all subjects, mean BOLD signal changes for 80%, 90%, 100%, 110% of the individual active motor threshold were 0.43%, 0.63%, 1.01%, 2.01% next to the individual functional finger tapping maximum, 0.73%, 0.91%, 1.34%, 2.21% next to the MNI-defined hand knob and 0.88%, 1.09%, 1.65%, 2.77% for the global maximum, respectively. CONCLUSION Our results show that the new setup for concurrent TMS/fMRI experiments using a dedicated MR coil array allows for high-sensitivity fMRI particularly at the site of stimulation. Contrary to the standard birdcage approach, the results also demonstrate that the new coil can be successfully used for multiband-accelerated EPI acquisition. The gain in flexibility due to the new coil can be easily combined with neuronavigation within the MR scanner to allow for accurate targeting in TMS/fMRI experiments.
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Affiliation(s)
- Lucia I Navarro de Lara
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Währinger Guertel 18-20, A-1090 Wien, Vienna, Austria; MR Center of Excellence, Medical University of Vienna, Vienna, Austria
| | - Martin Tik
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Währinger Guertel 18-20, A-1090 Wien, Vienna, Austria; MR Center of Excellence, Medical University of Vienna, Vienna, Austria
| | - Michael Woletz
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Währinger Guertel 18-20, A-1090 Wien, Vienna, Austria; MR Center of Excellence, Medical University of Vienna, Vienna, Austria
| | - Roberta Frass-Kriegl
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Währinger Guertel 18-20, A-1090 Wien, Vienna, Austria; MR Center of Excellence, Medical University of Vienna, Vienna, Austria
| | - Ewald Moser
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Währinger Guertel 18-20, A-1090 Wien, Vienna, Austria; MR Center of Excellence, Medical University of Vienna, Vienna, Austria
| | - Elmar Laistler
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Währinger Guertel 18-20, A-1090 Wien, Vienna, Austria; MR Center of Excellence, Medical University of Vienna, Vienna, Austria
| | - Christian Windischberger
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Währinger Guertel 18-20, A-1090 Wien, Vienna, Austria; MR Center of Excellence, Medical University of Vienna, Vienna, Austria.
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McCrimmon CM, Fu JL, Wang M, Lopes LS, Wang PT, Karimi-Bidhendi A, Liu CY, Heydari P, Nenadic Z, Do AH. Performance Assessment of a Custom, Portable, and Low-Cost Brain-Computer Interface Platform. IEEE Trans Biomed Eng 2017; 64:2313-2320. [PMID: 28207382 DOI: 10.1109/tbme.2017.2667579] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
OBJECTIVE Conventional brain-computer interfaces (BCIs) are often expensive, complex to operate, and lack portability, which confines their use to laboratory settings. Portable, inexpensive BCIs can mitigate these problems, but it remains unclear whether their low-cost design compromises their performance. Therefore, we developed a portable, low-cost BCI and compared its performance to that of a conventional BCI. METHODS The BCI was assembled by integrating a custom electroencephalogram (EEG) amplifier with an open-source microcontroller and a touchscreen. The function of the amplifier was first validated against a commercial bioamplifier, followed by a head-to-head comparison between the custom BCI (using four EEG channels) and a conventional 32-channel BCI. Specifically, five able-bodied subjects were cued to alternate between hand opening/closing and remaining motionless while the BCI decoded their movement state in real time and provided visual feedback through a light emitting diode. Subjects repeated the above task for a total of 10 trials, and were unaware of which system was being used. The performance in each trial was defined as the temporal correlation between the cues and the decoded states. RESULTS The EEG data simultaneously acquired with the custom and commercial amplifiers were visually similar and highly correlated ( ρ = 0.79). The decoding performances of the custom and conventional BCIs averaged across trials and subjects were 0.70 ± 0.12 and 0.68 ± 0.10, respectively, and were not significantly different. CONCLUSION The performance of our portable, low-cost BCI is comparable to that of the conventional BCIs. SIGNIFICANCE Platforms, such as the one developed here, are suitable for BCI applications outside of a laboratory.
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Scheef L, Nordmeyer-Massner JA, Smith-Collins APR, Müller N, Stegmann-Woessner G, Jankowski J, Gieseke J, Born M, Seitz H, Bartmann P, Schild HH, Pruessmann KP, Heep A, Boecker H. Functional Laterality of Task-Evoked Activation in Sensorimotor Cortex of Preterm Infants: An Optimized 3 T fMRI Study Employing a Customized Neonatal Head Coil. PLoS One 2017; 12:e0169392. [PMID: 28076368 PMCID: PMC5226735 DOI: 10.1371/journal.pone.0169392] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2016] [Accepted: 12/16/2016] [Indexed: 12/27/2022] Open
Abstract
Background Functional magnetic resonance imaging (fMRI) in neonates has been introduced as a non-invasive method for studying sensorimotor processing in the developing brain. However, previous neonatal studies have delivered conflicting results regarding localization, lateralization, and directionality of blood oxygenation level dependent (BOLD) responses in sensorimotor cortex (SMC). Amongst the confounding factors in interpreting neonatal fMRI studies include the use of standard adult MR-coils providing insufficient signal to noise, and liberal statistical thresholds, compromising clinical interpretation at the single subject level. Patients / methods Here, we employed a custom-designed neonatal MR-coil adapted and optimized to the head size of a newborn in order to improve robustness, reliability and validity of neonatal sensorimotor fMRI. Thirteen preterm infants with a median gestational age of 26 weeks were scanned at term-corrected age using a prototype 8-channel neonatal head coil at 3T (Achieva, Philips, Best, NL). Sensorimotor stimulation was elicited by passive extension/flexion of the elbow at 1 Hz in a block design. Analysis of temporal signal to noise ratio (tSNR) was performed on the whole brain and the SMC, and was compared to data acquired with an ‘adult’ 8 channel head coil published previously. Task-evoked activation was determined by single-subject SPM8 analyses, thresholded at p < 0.05, whole-brain FWE-corrected. Results Using a custom-designed neonatal MR-coil, we found significant positive BOLD responses in contralateral SMC after unilateral passive sensorimotor stimulation in all neonates (analyses restricted to artifact-free data sets = 8/13). Improved imaging characteristics of the neonatal MR-coil were evidenced by additional phantom and in vivo tSNR measurements: phantom studies revealed a 240% global increase in tSNR; in vivo studies revealed a 73% global and a 55% local (SMC) increase in tSNR, as compared to the ‘adult’ MR-coil. Conclusions Our findings strengthen the importance of using optimized coil settings for neonatal fMRI, yielding robust and reproducible SMC activation at the single subject level. We conclude that functional lateralization of SMC activation, as found in children and adults, is already present in the newborn period.
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Affiliation(s)
- Lukas Scheef
- Department of Radiology, University of Bonn, Bonn, Germany
| | | | | | - Nicole Müller
- Department of Neonatology, University of Bonn, Bonn, Germany
| | | | | | | | - Mark Born
- Department of Radiology, University of Bonn, Bonn, Germany
| | - Hermann Seitz
- Department of Mechanical Engineering and Marine Technology, University of Rostock, Rostock, Germany
| | - Peter Bartmann
- Department of Neonatology, University of Bonn, Bonn, Germany
| | - Hans H. Schild
- Department of Radiology, University of Bonn, Bonn, Germany
| | - Klaas P. Pruessmann
- Institute for Biomedical Engineering, University of Zurich and ETH Zurich, Zurich, Switzerland
| | - Axel Heep
- School of Clinical Sciences, University of Bristol, Bristol, United Kingdom
- Department of Neonatology, University of Bonn, Bonn, Germany
- * E-mail:
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Jing J, Dauwels J, Rakthanmanon T, Keogh E, Cash SS, Westover MB. Rapid annotation of interictal epileptiform discharges via template matching under Dynamic Time Warping. J Neurosci Methods 2016; 274:179-190. [PMID: 26944098 PMCID: PMC5519352 DOI: 10.1016/j.jneumeth.2016.02.025] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2016] [Revised: 02/26/2016] [Accepted: 02/29/2016] [Indexed: 10/22/2022]
Abstract
BACKGROUND EEG interpretation relies on experts who are in short supply. There is a great need for automated pattern recognition systems to assist with interpretation. However, attempts to develop such systems have been limited by insufficient expert-annotated data. To address these issues, we developed a system named NeuroBrowser for EEG review and rapid waveform annotation. NEW METHODS At the core of NeuroBrowser lies on ultrafast template matching under Dynamic Time Warping, which substantially accelerates the task of annotation. RESULTS Our results demonstrate that NeuroBrowser can reduce the time required for annotation of interictal epileptiform discharges by EEG experts by 20-90%, with an average of approximately 70%. COMPARISON WITH EXISTING METHOD(S) In comparison with conventional manual EEG annotation, NeuroBrowser is able to save EEG experts approximately 70% on average of the time spent in annotating interictal epileptiform discharges. We have already extracted 19,000+ interictal epileptiform discharges from 100 patient EEG recordings. To our knowledge this represents the largest annotated database of interictal epileptiform discharges in existence. CONCLUSION NeuroBrowser is an integrated system for rapid waveform annotation. While the algorithm is currently tailored to annotation of interictal epileptiform discharges in scalp EEG recordings, the concepts can be easily generalized to other waveforms and signal types.
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Affiliation(s)
- J Jing
- School of Electrical and Electronic Engineering, Nanyang Technological University, Singapore.
| | - J Dauwels
- School of Electrical and Electronic Engineering, Nanyang Technological University, Singapore.
| | - T Rakthanmanon
- Department of Computer Engineering, Kasetsart University, Thailand.
| | - E Keogh
- Department of Computer Science and Engineering, University of California, Riverside, CA, USA.
| | - S S Cash
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, MA, USA.
| | - M B Westover
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, MA, USA.
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Rios G, Lubenov E, Chi D, Roukes ML, Siapas AG. Nanofabricated Neural Probes for Dense 3-D Recordings of Brain Activity. Nano Lett 2016; 16:6857-6862. [PMID: 27766885 PMCID: PMC5108031 DOI: 10.1021/acs.nanolett.6b02673] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2016] [Revised: 09/17/2016] [Indexed: 05/19/2023]
Abstract
Computations in brain circuits involve the coordinated activation of large populations of neurons distributed across brain areas. However, monitoring neuronal activity in the brain of intact animals with high temporal and spatial resolution has remained a technological challenge. Here we address this challenge by developing dense, three-dimensional (3-D) electrode arrays for electrophysiology. The 3-D arrays constitute the front-end of a modular and configurable system architecture that enables monitoring neuronal activity with unprecedented scale and resolution.
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Affiliation(s)
- Gustavo Rios
- Division of Biology and Biological
Engineering, Division of Engineering and Applied
Science, Division of Physics, Mathematics, and Astronomy, and Kavli Nanoscience Institute, California Institute of Technology, Pasadena, California 91125, United States
| | - Evgueniy
V. Lubenov
- Division of Biology and Biological
Engineering, Division of Engineering and Applied
Science, Division of Physics, Mathematics, and Astronomy, and Kavli Nanoscience Institute, California Institute of Technology, Pasadena, California 91125, United States
| | - Derrick Chi
- Division of Biology and Biological
Engineering, Division of Engineering and Applied
Science, Division of Physics, Mathematics, and Astronomy, and Kavli Nanoscience Institute, California Institute of Technology, Pasadena, California 91125, United States
| | - Michael L. Roukes
- Division of Biology and Biological
Engineering, Division of Engineering and Applied
Science, Division of Physics, Mathematics, and Astronomy, and Kavli Nanoscience Institute, California Institute of Technology, Pasadena, California 91125, United States
- E-mail:
| | - Athanassios G. Siapas
- Division of Biology and Biological
Engineering, Division of Engineering and Applied
Science, Division of Physics, Mathematics, and Astronomy, and Kavli Nanoscience Institute, California Institute of Technology, Pasadena, California 91125, United States
- E-mail:
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Kamaldin N, Nasrallah FA, Goh JCH. A Magnetic Resonance Compatible Soft Wearable Robotic Glove for Hand Rehabilitation and Brain Imaging. IEEE Trans Neural Syst Rehabil Eng 2016; 25:782-793. [PMID: 28113591 DOI: 10.1109/tnsre.2016.2602941] [Citation(s) in RCA: 59] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
In this paper, we present the design, fabrication and evaluation of a soft wearable robotic glove, which can be used with functional Magnetic Resonance imaging (fMRI) during the hand rehabilitation and task specific training. The soft wearable robotic glove, called MR-Glove, consists of two major components: a) a set of soft pneumatic actuators and b) a glove. The soft pneumatic actuators, which are made of silicone elastomers, generate bending motion and actuate finger joints upon pressurization. The device is MR-compatible as it contains no ferromagnetic materials and operates pneumatically. Our results show that the device did not cause artifacts to fMRI images during hand rehabilitation and task-specific exercises. This study demonstrated the possibility of using fMRI and MR-compatible soft wearable robotic device to study brain activities and motor performances during hand rehabilitation, and to unravel the functional effects of rehabilitation robotics on brain stimulation.
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Yu KJ, Kuzum D, Hwang SW, Kim BH, Juul H, Kim NH, Won SM, Chiang K, Trumpis M, Richardson AG, Cheng H, Fang H, Thomson M, Bink H, Talos D, Seo KJ, Lee HN, Kang SK, Kim JH, Lee JY, Huang Y, Jensen FE, Dichter MA, Lucas TH, Viventi J, Litt B, Rogers JA. Bioresorbable silicon electronics for transient spatiotemporal mapping of electrical activity from the cerebral cortex. Nat Mater 2016; 15:782-791. [PMID: 27088236 PMCID: PMC4919903 DOI: 10.1038/nmat4624] [Citation(s) in RCA: 214] [Impact Index Per Article: 26.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/10/2015] [Accepted: 03/14/2016] [Indexed: 05/18/2023]
Abstract
Bioresorbable silicon electronics technology offers unprecedented opportunities to deploy advanced implantable monitoring systems that eliminate risks, cost and discomfort associated with surgical extraction. Applications include postoperative monitoring and transient physiologic recording after percutaneous or minimally invasive placement of vascular, cardiac, orthopaedic, neural or other devices. We present an embodiment of these materials in both passive and actively addressed arrays of bioresorbable silicon electrodes with multiplexing capabilities, which record in vivo electrophysiological signals from the cortical surface and the subgaleal space. The devices detect normal physiologic and epileptiform activity, both in acute and chronic recordings. Comparative studies show sensor performance comparable to standard clinical systems and reduced tissue reactivity relative to conventional clinical electrocorticography (ECoG) electrodes. This technology offers general applicability in neural interfaces, with additional potential utility in treatment of disorders where transient monitoring and modulation of physiologic function, implant integrity and tissue recovery or regeneration are required.
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Affiliation(s)
- Ki Jun Yu
- Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
- Frederick Seitz Materials Research Laboratory, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Duygu Kuzum
- Department of Bioengineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
- Center for Neuroengineering and Therapeutics, University of Pennsylvania, Philadelphia, PA 19104, USA
- Department of Electrical and Computer Engineering, University of California, San Diego, San Diego, CA 92093
| | - Suk-Won Hwang
- KU-KIST Graduate School of Converging Science and Technology, Korea University, Seoul 136-701, Republic of Korea
| | - Bong Hoon Kim
- Frederick Seitz Materials Research Laboratory, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
- Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Halvor Juul
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Nam Heon Kim
- Frederick Seitz Materials Research Laboratory, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
- Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Sang Min Won
- Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
- Frederick Seitz Materials Research Laboratory, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Ken Chiang
- Department of Biomedical Engineering, Duke University, Durham, NC 27708, USA
| | - Michael Trumpis
- Department of Biomedical Engineering, Duke University, Durham, NC 27708, USA
| | - Andrew G. Richardson
- Center for Neuroengineering and Therapeutics, University of Pennsylvania, Philadelphia, PA 19104, USA
- Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Huanyu Cheng
- Department of Engineering Science and Mechanics, Penn State University, University Park, PA 16802, USA
| | - Hui Fang
- Frederick Seitz Materials Research Laboratory, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
- Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Marissa Thomson
- Department of Bioengineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
- Center for Neuroengineering and Therapeutics, University of Pennsylvania, Philadelphia, PA 19104, USA
- Department of Chemical and Biomolecular Engineering University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | - Hank Bink
- Department of Bioengineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
- Center for Neuroengineering and Therapeutics, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Delia Talos
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Kyung Jin Seo
- Frederick Seitz Materials Research Laboratory, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
- Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Hee Nam Lee
- Frederick Seitz Materials Research Laboratory, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
- Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana- Champaign, Urbana, IL 61801, USA
| | - Seung-Kyun Kang
- Frederick Seitz Materials Research Laboratory, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
- Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Jae-Hwan Kim
- Frederick Seitz Materials Research Laboratory, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
- Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Jung Yup Lee
- Frederick Seitz Materials Research Laboratory, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
- Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana- Champaign, Urbana, IL 61801, USA
| | - Younggang Huang
- Department of Mechanical Engineering and Department of Civil and Environmental Engineering, Northwestern University, Evanston, IL 60208, USA
| | - Frances E. Jensen
- Center for Neuroengineering and Therapeutics, University of Pennsylvania, Philadelphia, PA 19104, USA
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Marc A. Dichter
- Center for Neuroengineering and Therapeutics, University of Pennsylvania, Philadelphia, PA 19104, USA
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Timothy H. Lucas
- Center for Neuroengineering and Therapeutics, University of Pennsylvania, Philadelphia, PA 19104, USA
- Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Jonathan Viventi
- Department of Biomedical Engineering, Duke University, Durham, NC 27708, USA
| | - Brian Litt
- Department of Bioengineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
- Center for Neuroengineering and Therapeutics, University of Pennsylvania, Philadelphia, PA 19104, USA
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
- To whom correspondence should be addressed. or
| | - John A. Rogers
- Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
- Frederick Seitz Materials Research Laboratory, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
- Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
- To whom correspondence should be addressed. or
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Yee JR, Kenkel WM, Kulkarni P, Moore K, Perkeybile AM, Toddes S, Amacker JA, Carter CS, Ferris CF. BOLD fMRI in awake prairie voles: A platform for translational social and affective neuroscience. Neuroimage 2016; 138:221-232. [PMID: 27238726 DOI: 10.1016/j.neuroimage.2016.05.046] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2016] [Revised: 05/14/2016] [Accepted: 05/17/2016] [Indexed: 01/03/2023] Open
Abstract
The advancement of neuroscience depends on continued improvement in methods and models. Here, we present novel techniques for the use of awake functional magnetic resonance imaging (fMRI) in the prairie vole (Microtus ochrogaster) - an important step forward in minimally-invasive measurement of neural activity in a non-traditional animal model. Imaging neural responses in prairie voles, a species studied for its propensity to form strong and selective social bonds, is expected to greatly advance our mechanistic understanding of complex social and affective processes. The use of ultra-high-field fMRI allows for recording changes in region-specific activity throughout the entire brain simultaneously and with high temporal and spatial resolutions. By imaging neural responses in awake animals, with minimal invasiveness, we are able to avoid the confound of anesthesia, broaden the scope of possible stimuli, and potentially make use of repeated scans from the same animals. These methods are made possible by the development of an annotated and segmented 3D vole brain atlas and software for image analysis. The use of these methods in the prairie vole provides an opportunity to broaden neuroscientific investigation of behavior via a comparative approach, which highlights the ethological relevance of pro-social behaviors shared between voles and humans, such as communal breeding, selective social bonds, social buffering of stress, and caregiving behaviors. Results using these methods show that fMRI in the prairie vole is capable of yielding robust blood oxygen level dependent (BOLD) signal changes in response to hypercapnic challenge (inhaled 5% CO2), region-specific physical challenge (unilateral whisker stimulation), and presentation of a set of novel odors. Complementary analyses of repeated restraint sessions in the imaging hardware suggest that voles do not require acclimation to this procedure. Taken together, awake vole fMRI represents a new arena of neurobiological study outside the realm of traditional rodent models.
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Affiliation(s)
- J R Yee
- Dept. of Psychology, Northeastern University, United States; Kinsey Institute, Indiana University, United States.
| | - W M Kenkel
- Dept. of Psychology, Northeastern University, United States; Kinsey Institute, Indiana University, United States
| | - P Kulkarni
- Dept. of Psychology, Northeastern University, United States
| | - K Moore
- Dept. of Psychology, Northeastern University, United States
| | - A M Perkeybile
- Dept. of Psychology, Northeastern University, United States
| | - S Toddes
- Dept. of Psychology, Northeastern University, United States
| | - J A Amacker
- Dept. of Psychology, Northeastern University, United States
| | - C S Carter
- Kinsey Institute, Indiana University, United States
| | - C F Ferris
- Dept. of Psychology, Northeastern University, United States
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Maziero D, Velasco TR, Hunt N, Payne E, Lemieux L, Salmon CEG, Carmichael DW. Towards motion insensitive EEG-fMRI: Correcting motion-induced voltages and gradient artefact instability in EEG using an fMRI prospective motion correction (PMC) system. Neuroimage 2016; 138:13-27. [PMID: 27157789 DOI: 10.1016/j.neuroimage.2016.05.003] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2015] [Revised: 04/05/2016] [Accepted: 05/01/2016] [Indexed: 11/17/2022] Open
Abstract
The simultaneous acquisition of electroencephalography and functional magnetic resonance imaging (EEG-fMRI) is a multimodal technique extensively applied for mapping the human brain. However, the quality of EEG data obtained within the MRI environment is strongly affected by subject motion due to the induction of voltages in addition to artefacts caused by the scanning gradients and the heartbeat. This has limited its application in populations such as paediatric patients or to study epileptic seizure onset. Recent work has used a Moiré-phase grating and a MR-compatible camera to prospectively update image acquisition and improve fMRI quality (prospective motion correction: PMC). In this study, we use this technology to retrospectively reduce the spurious voltages induced by motion in the EEG data acquired inside the MRI scanner, with and without fMRI acquisitions. This was achieved by modelling induced voltages from the tracking system motion parameters; position and angles, their first derivative (velocities) and the velocity squared. This model was used to remove the voltages related to the detected motion via a linear regression. Since EEG quality during fMRI relies on a temporally stable gradient artefact (GA) template (calculated from averaging EEG epochs matched to scan volume or slice acquisition), this was evaluated in sessions both with and without motion contamination, and with and without PMC. We demonstrate that our approach is capable of significantly reducing motion-related artefact with a magnitude of up to 10mm of translation, 6° of rotation and velocities of 50mm/s, while preserving physiological information. We also demonstrate that the EEG-GA variance is not increased by the gradient direction changes associated with PMC. Provided a scan slice-based GA template is used (rather than a scan volume GA template) we demonstrate that EEG variance during motion can be supressed towards levels found when subjects are still. In summary, we show that PMC can be used to dramatically improve EEG quality during large amplitude movements, while benefiting from previously reported improvements in fMRI quality, and does not affect EEG data quality in the absence of large amplitude movements.
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Affiliation(s)
- Danilo Maziero
- Developmental Imaging and Biophysics Section, UCL Institute of Child Health, London, UK; InBrain Lab, Department of Physics, FFLCRP, University of São Paulo, Ribeirão Preto, SP, Brazil.
| | - Tonicarlo R Velasco
- Epilepsy Surgery Centre, Department of Neuroscience, Faculty of Medicine, University of São Paulo, Ribeirão Preto, SP, Brazil
| | - Nigel Hunt
- Division of Craniofacial Developmental Sciences, UCL Eastman Dental Institute, London, UK
| | - Edwin Payne
- Division of Craniofacial Developmental Sciences, UCL Eastman Dental Institute, London, UK
| | - Louis Lemieux
- Department of Clinical and Experimental Epilepsy, UCL Institute of Neurology, London, UK
| | - Carlos E G Salmon
- InBrain Lab, Department of Physics, FFLCRP, University of São Paulo, Ribeirão Preto, SP, Brazil
| | - David W Carmichael
- Developmental Imaging and Biophysics Section, UCL Institute of Child Health, London, UK
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34
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Chang CW, Hsin YL, Liu W. A Spatially Focused Method for High Density Electrode-Based Functional Brain Mapping Applications. IEEE Trans Neural Syst Rehabil Eng 2016; 24:1029-1040. [PMID: 27046851 DOI: 10.1109/tnsre.2016.2537146] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Mapping the electric field of the brain with electrodes benefits from its superior temporal resolution but is prone to low spatial resolution property comparing with other modalities such as fMRI, which can directly impact the precision of clinical diagnosis. Simulations show that dense arrays with straightforwardly miniaturized electrodes in terms of size and pitch may not improve the spatial resolution but only strengthen the cross coupling between adjacent channels due to volume conduction. We present a new spatially focused method to improve the electrode spatial selectivity and consequently suppress the neural signal coupling from the sources in the vicinity. Compared with existing spatial filtering methods with fixed coefficients, the proposed method is adaptively optimized for the geometric parameters of the recording electrode arrays, including electrode size, pitch and source depth. The effective spatial bandwidth, characterized as Radius of Half Power, can be reduced by about 70% for ECoG and the case of distant sources scenarios. The proposed method has been applied to the analysis of high-frequency oscillations (HFOs) in seizures to study the ictal pathway in the epileptogenic region. The results reveal lucid HFO wavefront propagation in both preictal and ictal stages due to a 75% reduction in the coupling effect. The results also show that a specific power threshold of preictal HFOs is needed in order to initiate an epileptic seizure. This demonstrates that our method indeed facilitates the investigation of complex neurobiological signals preprocessing applications.
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Batres-Mendoza P, Montoro-Sanjose CR, Guerra-Hernandez EI, Almanza-Ojeda DL, Rostro-Gonzalez H, Romero-Troncoso RJ, Ibarra-Manzano MA. Quaternion-Based Signal Analysis for Motor Imagery Classification from Electroencephalographic Signals. Sensors (Basel) 2016; 16:s16030336. [PMID: 26959029 PMCID: PMC4813911 DOI: 10.3390/s16030336] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/27/2016] [Revised: 02/26/2016] [Accepted: 02/29/2016] [Indexed: 11/16/2022]
Abstract
Quaternions can be used as an alternative to model the fundamental patterns of electroencephalographic (EEG) signals in the time domain. Thus, this article presents a new quaternion-based technique known as quaternion-based signal analysis (QSA) to represent EEG signals obtained using a brain-computer interface (BCI) device to detect and interpret cognitive activity. This quaternion-based signal analysis technique can extract features to represent brain activity related to motor imagery accurately in various mental states. Experimental tests in which users where shown visual graphical cues related to left and right movements were used to collect BCI-recorded signals. These signals were then classified using decision trees (DT), support vector machine (SVM) and k-nearest neighbor (KNN) techniques. The quantitative analysis of the classifiers demonstrates that this technique can be used as an alternative in the EEG-signal modeling phase to identify mental states.
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Affiliation(s)
- Patricia Batres-Mendoza
- Laboratorio de Sistemas Bioinspirados, Departamento de Ingeniería Electrónica, DICIS, Universidad de Guanajuato, Carr. Salamanca-Valle de Santiago KM. 3.5 + 1.8 Km., Salamanca 36885, Mexico.
| | - Carlos R Montoro-Sanjose
- Departamento de Arte y Empresa, DICIS, Universidad de Guanajuato, Carr. Salamanca-Valle de Santiago KM. 3.5 + 1.8 Km., Salamanca 36885, Mexico.
- Cuerpo Académico de Telemática, DICIS, Universidad de Guanajuato, Carr. Salamanca-Valle de Santiago KM. 3.5 + 1.8 Km., Salamanca 36885, Mexico.
| | - Erick I Guerra-Hernandez
- Laboratorio de Sistemas Bioinspirados, Departamento de Ingeniería Electrónica, DICIS, Universidad de Guanajuato, Carr. Salamanca-Valle de Santiago KM. 3.5 + 1.8 Km., Salamanca 36885, Mexico.
| | - Dora L Almanza-Ojeda
- Laboratorio de Procesamiento Digital de Señales, Departamento de Ingeniería Electrónica, DICIS, Universidad de Guanajuato, Carr. Salamanca-Valle de Santiago KM. 3.5 + 1.8 Km., Salamanca 36885, Mexico.
| | - Horacio Rostro-Gonzalez
- Laboratorio de Sistemas Bioinspirados, Departamento de Ingeniería Electrónica, DICIS, Universidad de Guanajuato, Carr. Salamanca-Valle de Santiago KM. 3.5 + 1.8 Km., Salamanca 36885, Mexico.
- Cuerpo Académico de Telemática, DICIS, Universidad de Guanajuato, Carr. Salamanca-Valle de Santiago KM. 3.5 + 1.8 Km., Salamanca 36885, Mexico.
| | - Rene J Romero-Troncoso
- Cuerpo Académico de Telemática, DICIS, Universidad de Guanajuato, Carr. Salamanca-Valle de Santiago KM. 3.5 + 1.8 Km., Salamanca 36885, Mexico.
- Departamento de Ingeniería Electrónica, DICIS, Universidad de Guanajuato, Carr. Salamanca-Valle de Santiago KM. 3.5 + 1.8 Km., Salamanca 36885, Mexico.
| | - Mario A Ibarra-Manzano
- Cuerpo Académico de Telemática, DICIS, Universidad de Guanajuato, Carr. Salamanca-Valle de Santiago KM. 3.5 + 1.8 Km., Salamanca 36885, Mexico.
- Laboratorio de Procesamiento Digital de Señales, Departamento de Ingeniería Electrónica, DICIS, Universidad de Guanajuato, Carr. Salamanca-Valle de Santiago KM. 3.5 + 1.8 Km., Salamanca 36885, Mexico.
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Buzzi J, De Momi E, Baratelli FM, Giacometti M, Fiocchi S, Parazzini M, Ravazzani P, Ferrigno G. A new handheld electromagnetic cortical stimulator for brain mapping during open skull neurosurgery: a feasibility study. Annu Int Conf IEEE Eng Med Biol Soc 2016; 2015:3387-90. [PMID: 26737019 DOI: 10.1109/embc.2015.7319119] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Transcranial magnetic stimulations have provided invaluable tools for investigating nervous system functions in a preoperative context; in this paper we propose an innovative tool to extend the magnetic stimulation to an open skull context as a promising approach to map the brain cortex. The present gold standard for intraoperative functional mapping of the brain cortex, the direct brain stimulation, has a low spatial resolution and limited penetration and focusing capabilities. The magnetic stimulatory device that we present, is designed to overcome these limitations, while working with low currents and voltages. In the present work we propose an early study of feasibility, in which the possibility of exploiting a train of fast changing magnetic fields to reach the neuron's current thresholds is investigated. Measurements of electric field intensity at different distances from the coil, showed that the magnetic stimulator realized is capable of delivering an electric field on a loop of wire theoretically sufficient to evoke neuron's action potential, thus showing the approach' feasibility.
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Bai R, Klaus A, Bellay T, Stewart C, Pajevic S, Nevo U, Merkle H, Plenz D, Basser PJ. Simultaneous calcium fluorescence imaging and MR of ex vivo organotypic cortical cultures: a new test bed for functional MRI. NMR Biomed 2015; 28:1726-1738. [PMID: 26510537 DOI: 10.1002/nbm.3424] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2015] [Revised: 09/03/2015] [Accepted: 09/06/2015] [Indexed: 06/05/2023]
Abstract
Recently, several new functional (f)MRI contrast mechanisms including diffusion, phase imaging, proton density, etc. have been proposed to measure neuronal activity more directly and accurately than blood-oxygen-level dependent (BOLD) fMRI. However, these approaches have proved difficult to reproduce, mainly because of the dearth of reliable and robust test systems to vet and validate them. Here we describe the development and testing of such a test bed for non-BOLD fMRI. Organotypic cortical cultures were used as a stable and reproducible biological model of neuronal activity that shows spontaneous activity similar to that of in vivo brain cortex without any hemodynamic confounds. An open-access, single-sided magnetic resonance (MR) "profiler" consisting of four permanent magnets with magnetic field of 0.32 T was used in this study to perform MR acquisition. A fluorescence microscope with long working distance objective was mounted on the top of a custom-designed chamber that keeps the organotypic culture vital, and the MR system was mounted on the bottom of the chamber to achieve real-time simultaneous calcium fluorescence optical imaging and MR acquisition on the same specimen. In this study, the reliability and performance of the proposed test bed were demonstrated by a conventional CPMG MR sequence acquired simultaneously with calcium imaging, which is a well-characterized measurement of neuronal activity. This experimental design will make it possible to correlate directly the other candidate functional MR signals to the optical indicia of neuronal activity in the future.
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Affiliation(s)
- Ruiliang Bai
- Section on Tissue Biophysics and Biomimetics, PPITS, NICHD, National Institutes of Health, Bethesda, Maryland, USA
- Biophysics Program, Institute for Physical Science and Technology, University of Maryland, College Park, USA
| | - Andreas Klaus
- Section on Critical Brain Dynamics, LSN, NIMH, National Institutes of Health, Bethesda, Maryland, USA
| | - Tim Bellay
- Section on Critical Brain Dynamics, LSN, NIMH, National Institutes of Health, Bethesda, Maryland, USA
| | - Craig Stewart
- Section on Critical Brain Dynamics, LSN, NIMH, National Institutes of Health, Bethesda, Maryland, USA
| | - Sinisa Pajevic
- Mathematical and Statistical Computing Laboratory, Division of Computational Bioscience, Center for Information Technology, NIH, Bethesda, Maryland, USA
| | - Uri Nevo
- Department of Biomedical Engineering, Tel-Aviv University, Tel-Aviv, Israel
| | - Hellmut Merkle
- Laboratory for Functional and Molecular Imaging, NINDS, National Institutes of Health, Bethesda, Maryland, USA
| | - Dietmar Plenz
- Section on Critical Brain Dynamics, LSN, NIMH, National Institutes of Health, Bethesda, Maryland, USA
| | - Peter J Basser
- Section on Tissue Biophysics and Biomimetics, PPITS, NICHD, National Institutes of Health, Bethesda, Maryland, USA
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Abstract
An implanted electroencephalogram (EEG) recorder would help diagnose infrequent seizure-like events. A proof-of-concept study quantified the electrical characteristics of the electrodes planned for the proposed recorder. The electrodes were implanted in an ovine model for eight weeks. Electrode impedance was less than 800 Ohms throughout the study. A frequency-domain determination of sedation performed similarly for surface versus implanted electrodes throughout the study. The time-domain correlation between an implanted electrode and a surface electrode was almost as high as between two surface electrodes (0.86 versus 0.92). EEG-certified clinicians judged that the implanted electrode quality was adequate to excellent and that the implanted electrodes provided the same clinical information as surface electrodes except for a noticeable amplitude difference. No significant issues were found that would stop development of the EEG recorder.
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Xin Y, Li WXY, Zhang Z, Cheung RCC, Song D, Berger TW. An Application Specific Instruction Set Processor (ASIP) for Adaptive Filters in Neural Prosthetics. IEEE/ACM Trans Comput Biol Bioinform 2015; 12:1034-1047. [PMID: 26451817 DOI: 10.1109/tcbb.2015.2440248] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Neural coding is an essential process for neuroprosthetic design, in which adaptive filters have been widely utilized. In a practical application, it is needed to switch between different filters, which could be based on continuous observations or point process, when the neuron models, conditions, or system requirements have changed. As candidates of coding chip for neural prostheses, low-power general purpose processors are not computationally efficient especially for large scale neural population coding. Application specific integrated circuits (ASICs) do not have flexibility to switch between different adaptive filters while the cost for design and fabrication is formidable. In this research work, we explore an application specific instruction set processor (ASIP) for adaptive filters in neural decoding activity. The proposed architecture focuses on efficient computation for the most time-consuming matrix/vector operations among commonly used adaptive filters, being able to provide both flexibility and throughput. Evaluation and implementation results are provided to demonstrate that the proposed ASIP design is area-efficient while being competitive to commercial CPUs in computational performance.
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40
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Sieu LA, Bergel A, Tiran E, Deffieux T, Pernot M, Gennisson JL, Tanter M, Cohen I. EEG and functional ultrasound imaging in mobile rats. Nat Methods 2015; 12:831-4. [PMID: 26237228 PMCID: PMC4671306 DOI: 10.1038/nmeth.3506] [Citation(s) in RCA: 83] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2015] [Accepted: 06/26/2015] [Indexed: 11/08/2022]
Abstract
We developed an integrated experimental framework that extends the brain exploration capabilities of functional ultrasound imaging to awake and mobile rats. In addition to acquiring hemodynamic data, this method further allows parallel access to electroencephalography (EEG) recordings of neuronal activity. We illustrate this approach with two proofs of concept: a behavioral study on theta rhythm activation in a maze running task and a disease-related study on spontaneous epileptic seizures.
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Affiliation(s)
- Lim-Anna Sieu
- Institut de Biologie Paris-Seine, INSERM U1130, CNRS UMR 8246, University Pierre et Marie Curie UMCR18, Paris, France
- Institut des Neurosciences Translationnelles de Paris, Paris, France
| | - Antoine Bergel
- Institut de Biologie Paris-Seine, INSERM U1130, CNRS UMR 8246, University Pierre et Marie Curie UMCR18, Paris, France
- Ecole Doctorale Frontières du Vivant (FdV), Programme Bettencourt, Universite´ Paris Diderot, Sorbonne Paris Cite´, Paris, France
| | - Elodie Tiran
- Institut Langevin, Ecole Supérieure de Physique et de Chimie Industrielles de la ville de Paris ParisTech, Paris Sciences et Lettres Research University, CNRS UMR 7587, INSERM U979, Paris, France
| | - Thomas Deffieux
- Institut Langevin, Ecole Supérieure de Physique et de Chimie Industrielles de la ville de Paris ParisTech, Paris Sciences et Lettres Research University, CNRS UMR 7587, INSERM U979, Paris, France
| | - Mathieu Pernot
- Institut Langevin, Ecole Supérieure de Physique et de Chimie Industrielles de la ville de Paris ParisTech, Paris Sciences et Lettres Research University, CNRS UMR 7587, INSERM U979, Paris, France
| | - Jean-Luc Gennisson
- Institut Langevin, Ecole Supérieure de Physique et de Chimie Industrielles de la ville de Paris ParisTech, Paris Sciences et Lettres Research University, CNRS UMR 7587, INSERM U979, Paris, France
| | - Mickaël Tanter
- Institut Langevin, Ecole Supérieure de Physique et de Chimie Industrielles de la ville de Paris ParisTech, Paris Sciences et Lettres Research University, CNRS UMR 7587, INSERM U979, Paris, France
| | - Ivan Cohen
- Institut de Biologie Paris-Seine, INSERM U1130, CNRS UMR 8246, University Pierre et Marie Curie UMCR18, Paris, France
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Dimitriadis SI, Sun Y, Kwok K, Laskaris NA, Bezerianos A. A tensorial approach to access cognitive workload related to mental arithmetic from EEG functional connectivity estimates. Annu Int Conf IEEE Eng Med Biol Soc 2015; 2013:2940-3. [PMID: 24110343 DOI: 10.1109/embc.2013.6610156] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
The association of functional connectivity patterns with particular cognitive tasks has long been a topic of interest in neuroscience, e.g., studies of functional connectivity have demonstrated its potential use for decoding various brain states. However, the high-dimensionality of the pairwise functional connectivity limits its usefulness in some real-time applications. In the present study, the methodology of tensor subspace analysis (TSA) is used to reduce the initial high-dimensionality of the pairwise coupling in the original functional connectivity network to a space of condensed descriptive power, which would significantly decrease the computational cost and facilitate the differentiation of brain states. We assess the feasibility of the proposed method on EEG recordings when the subject was performing mental arithmetic task which differ only in the difficulty level (easy: 1-digit addition v.s. 3-digit additions). Two different cortical connective networks were detected, and by comparing the functional connectivity networks in different work states, it was found that the task-difficulty is best reflected in the connectivity structure of sub-graphs extending over parietooccipital sites. Incorporating this data-driven information within original TSA methodology, we succeeded in predicting the difficulty level from connectivity patterns in an efficient way that can be implemented so as to work in real-time.
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Wang H, Lenglet C, Akkin T. Structure tensor analysis of serial optical coherence scanner images for mapping fiber orientations and tractography in the brain. J Biomed Opt 2015; 20:036003. [PMID: 25741662 PMCID: PMC4350401 DOI: 10.1117/1.jbo.20.3.036003] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2014] [Accepted: 02/19/2015] [Indexed: 05/05/2023]
Abstract
Quantitative investigations of fiber orientation and structural connectivity at microscopic resolution have led to great challenges for current neuroimaging techniques. Here, we present a structure tensor (ST) analysis of ex vivo rat brain images acquired by a multicontrast (MC) serial optical coherence scanner. The ST considers the gradients of images in local neighbors to generate a matrix whose eigen-decomposition can estimate the local features such as the edges, anisotropy, and orientation of tissue constituents. This computational analysis is applied on the conventional- and polarization-based contrasts of optical coherence tomography. The three-dimensional (3-D) fiber orientation maps are computed from the image stacks of sequential scans both at mesoresolution for a global view and at high-resolution for the details. The computational orientation maps demonstrate a good agreement with the optic axis orientation contrast which measures the in-plane fiber orientation. Moreover, tractography is implemented using the directional information extracted from the 3-D ST. The study provides a unique opportunity to leverage MC high-resolution information to map structural connectivity of the whole brain.
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Affiliation(s)
- Hui Wang
- University of Minnesota, Department of Biomedical Engineering, Minneapolis, Minnesota 55455, United States
- Address all correspondence to: Hui Wang, E-mail:
| | - Christophe Lenglet
- University of Minnesota, Center for Magnetic Resonance Research, Department of Radiology, Minneapolis, Minnesota 55455, United States
| | - Taner Akkin
- University of Minnesota, Department of Biomedical Engineering, Minneapolis, Minnesota 55455, United States
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Deputat IS, Gribanov AV, Nekhoroshkova AN, Moroz TP. [The DC-potential of the brain in older women with postural instability]. Adv Gerontol 2015; 28:749-754. [PMID: 28509466] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
The article presents the results of studies of the DC-potential of the brain level distribution in elderly women with postural instability. Analysis of the DC-potential of the brain level distribution was held by mapping obtained by measuring the monopolar values of the DC-potential of the brain and calculating deviations in each of the leads from the average records which were registered in all areas of the head. It is established that elderly women with postural instability DC-potential of the brain level distribution are characterized by increasing in background values and rigid structure of the interaction between brain regions. The disturbance of the principle of the dome-shaped DC-potential of the brain level distribution due to the alignment of values for brain regions was revealed. Factor model with postural instability reflects the control strengthening over the potential falls from the frontal areas of the brain.
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Affiliation(s)
- I S Deputat
- M. V. Lomonosov Institute of Medical and Biological Research, Arkhangelsk, 163045, Russian Federation;
| | - A V Gribanov
- M. V. Lomonosov Institute of Medical and Biological Research, Arkhangelsk, 163045, Russian Federation;
| | - A N Nekhoroshkova
- M. V. Lomonosov Institute of Medical and Biological Research, Arkhangelsk, 163045, Russian Federation;
| | - T P Moroz
- M. V. Lomonosov Institute of Medical and Biological Research, Arkhangelsk, 163045, Russian Federation;
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Abstract
Background:Functional neuroimaging can address some challenges of seizure localization, and sometimes preclude the need for EEG recording using intracranial electrodes. Ictal Single Photon Emission Computed Tomography (SPECT) has developed into an important tool in the presurgical evaluation of patients with medically-intractable localization-related epilepsy. The purpose of the study was to determine whether the development of a programme using trained nurses to perform ictal injections enabled a more efficient delivery of radiopharmaceuticals and therefore a greater sensitivity and specificity of outcome.Methods:In our epilepsy unit, nursing staff inject 99mTc-HMPAO at bedside, during or at seizure onset. Brain SPECT is performed later on a gamma camera.Results:Since the implementation of the new protocol (February 2005), 57 scans have been performed: 22 ictal and 35 interictal. Latency of ictal injection was found to be 5-40 seconds (mean 19.7 sec, standard deviation (SD) 10.4). Only 20% of reconstituted radiopharmaceutical vials were not used. Contamination rate was nil. Sixty three percent of SPECT studies were concordant with standard presurgical evaluation.Conclusion:The latency of injections and the percentage of unused vials indicated an efficient and effective protocol compared to the literature. Our results show that ictal SPECT can be a safe, noninvasive procedure performed on a routine basis in the epilepsy unit when appropriately trained support staff are incorporated into a structured multidisciplinary programme.
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Affiliation(s)
- J G Burneo
- Epilepsy Programme, University of Western Ontario, London, ON, Canada
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Abstract
A brief review of previous studies is presented on tonotopic organization of primary auditory cortex (AI) in humans. Based on the place theory for pitch perception, in which place information from the cochlea is used to derive pitch, a well-organized layout of tonotopic map is likely in human AI. The conventional view of tonotopy in human AI is a layout inwhich the medial-to-lateral portion of Heschl's gyrus represents high-to-low frequency tones. However, we have shown that the equivalent current dipole (BCD) in auditory evoked magnetic fields in the rising phase of N100m response dynamically moves along the long axis of Heschl's gyrus. Based on analyses of the current sources for high-pitched and low-pitched tones in the right and left hemispheres, we propose an alternative tonotopic map in human AI. In the right AI, isofrequency bands for each tone frequency are parallell to the first transverse sulcus; on the other hand, the layout for tonotopy in the left AI seems poorly organized. The validity of single dipole modelling in the calculation of a moving source and the discrepancy as to tonotopic maps in the results between auditory evoked fields or intracerebral recordings and neuroimaging studies also are discussed. The difference in the layout of isofrequency bands between the right and left auditory cortices may reflect distinct functional roles in auditory information processing such as pitch versus phonetic analysis.
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Affiliation(s)
- Isamu Ozaki
- Faculty of Health Sciences, Aomori University of Health and Welfare, Aomori, Japan
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Streitberger KJ, Reiss-Zimmermann M, Freimann FB, Bayerl S, Guo J, Arlt F, Wuerfel J, Braun J, Hoffmann KT, Sack I. High-resolution mechanical imaging of glioblastoma by multifrequency magnetic resonance elastography. PLoS One 2014; 9:e110588. [PMID: 25338072 PMCID: PMC4206430 DOI: 10.1371/journal.pone.0110588] [Citation(s) in RCA: 97] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2014] [Accepted: 09/17/2014] [Indexed: 12/14/2022] Open
Abstract
Objective To generate high-resolution maps of the viscoelastic properties of human brain parenchyma for presurgical quantitative assessment in glioblastoma (GB). Methods Twenty-two GB patients underwent routine presurgical work-up supplemented by additional multifrequency magnetic resonance elastography. Two three-dimensional viscoelastic parameter maps, magnitude |G*|, and phase angle φ of the complex shear modulus were reconstructed by inversion of full wave field data in 2-mm isotropic resolution at seven harmonic drive frequencies ranging from 30 to 60 Hz. Results Mechanical brain maps confirmed that GB are composed of stiff and soft compartments, resulting in high intratumor heterogeneity. GB could be easily differentiated from healthy reference tissue by their reduced viscous behavior quantified by φ (0.37±0.08 vs. 0.58±0.07). |G*|, which in solids more relates to the material's stiffness, was significantly reduced in GB with a mean value of 1.32±0.26 kPa compared to 1.54±0.27 kPa in healthy tissue (P = 0.001). However, some GB (5 of 22) showed increased stiffness. Conclusion GB are generally less viscous and softer than healthy brain parenchyma. Unrelated to the morphology-based contrast of standard magnetic resonance imaging, elastography provides an entirely new neuroradiological marker and contrast related to the biomechanical properties of tumors.
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Affiliation(s)
| | | | | | - Simon Bayerl
- Department of Neurosurgery, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Jing Guo
- Department of Radiology, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Felix Arlt
- Department of Neurosurgery, Universitätsmedizin Leipzig, Leipzig, Germany
| | - Jens Wuerfel
- Institute of Neuroradiology, Universitätsmedizin Göttingen, Göttingen, Germany
- NeuroCure, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Jürgen Braun
- Institute of Medical Informatics, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | | | - Ingolf Sack
- Department of Radiology, Charité - Universitätsmedizin Berlin, Berlin, Germany
- * E-mail:
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Schoene‐Bake J, Keller SS, Niehusmann P, Volmering E, Elger C, Deppe M, Weber B. In vivo mapping of hippocampal subfields in mesial temporal lobe epilepsy: relation to histopathology. Hum Brain Mapp 2014; 35:4718-28. [PMID: 24638919 PMCID: PMC6869541 DOI: 10.1002/hbm.22506] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2013] [Revised: 12/10/2013] [Accepted: 02/25/2014] [Indexed: 11/06/2022] Open
Abstract
A particularly popular automated magnetic resonance imaging (MRI) hippocampal subfield mapping technique is the one described by Van Leemput et al. (2009: Hippocampus 19:549-557) that is currently distributed with FreeSurfer software. This method assesses the probabilistic locations of subfields based on a priori knowledge of subfield topology determined from high-field MRI. Many studies have applied this technique to conventionally acquired T1-weighted MRI data. In the present study, we investigated the relationship between this technique applied to conventional T1-weighted MRI data acquired at 3 T and postsurgical hippocampal histology in patients with medically intractable mesial temporal lobe epilepsy (mTLE) and hippocampal sclerosis (HS). Patients with mTLE (n = 82) exhibited significant volume loss of ipsilateral CA1, CA2-3, CA4-dentate gyrus (DG), subiculum, and fimbria relative to controls (n = 81). Histopathological analysis indicated that the most significant neuronal loss was observed in CA1, then CA4 and CA3, and more subtle neuronal loss in CA2, consistent with classical HS. Neuronal density of CA1 significantly correlated with MRI-determined volume of CA1, and increasingly so with CA2-3 and CA4-DG. Patients with increased HS based on histopathology had greater volume loss of the ipsilateral hippocampal regions on MRI. We conclude by suggesting that whilst time efficient and fully reproducible when applied to conventional single acquisition sequences, the use of the automated subfield technique described here may necessitate the application to multiacquisition high-resolution MR sequences for accurate delineation of hippocampal subfields.
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Affiliation(s)
- Jan‐Christoph Schoene‐Bake
- Department of EpileptologyUniversity of BonnBonnGermany
- Department of NeuroCognition/ImagingLife & Brain Research CenterBonnGermany
| | - Simon S. Keller
- Department of Molecular and Clinical PharmacologyInstitute of Translational Medicine, University of LiverpoolLiverpoolUnited Kingdom
- Department of Clinical NeuroscienceInstitute of Psychiatry, King's College LondonLondonUnited Kingdom
| | | | | | | | - Michael Deppe
- Department of NeurologyUniversity of MünsterMünsterGermany
| | - Bernd Weber
- Department of EpileptologyUniversity of BonnBonnGermany
- Department of NeuroCognition/ImagingLife & Brain Research CenterBonnGermany
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Gupta D, Hill NJ, Adamo MA, Ritaccio A, Schalk G. Localizing ECoG electrodes on the cortical anatomy without post-implantation imaging. Neuroimage Clin 2014; 6:64-76. [PMID: 25379417 PMCID: PMC4215521 DOI: 10.1016/j.nicl.2014.07.015] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2014] [Revised: 07/26/2014] [Accepted: 07/29/2014] [Indexed: 01/22/2023]
Abstract
INTRODUCTION Electrocorticographic (ECoG) grids are placed subdurally on the cortex in people undergoing cortical resection to delineate eloquent cortex. ECoG signals have high spatial and temporal resolution and thus can be valuable for neuroscientific research. The value of these data is highest when they can be related to the cortical anatomy. Existing methods that establish this relationship rely either on post-implantation imaging using computed tomography (CT), magnetic resonance imaging (MRI) or X-Rays, or on intra-operative photographs. For research purposes, it is desirable to localize ECoG electrodes on the brain anatomy even when post-operative imaging is not available or when intra-operative photographs do not readily identify anatomical landmarks. METHODS We developed a method to co-register ECoG electrodes to the underlying cortical anatomy using only a pre-operative MRI, a clinical neuronavigation device (such as BrainLab VectorVision), and fiducial markers. To validate our technique, we compared our results to data collected from six subjects who also had post-grid implantation imaging available. We compared the electrode coordinates obtained by our fiducial-based method to those obtained using existing methods, which are based on co-registering pre- and post-grid implantation images. RESULTS Our fiducial-based method agreed with the MRI-CT method to within an average of 8.24 mm (mean, median = 7.10 mm) across 6 subjects in 3 dimensions. It showed an average discrepancy of 2.7 mm when compared to the results of the intra-operative photograph method in a 2D coordinate system. As this method does not require post-operative imaging such as CTs, our technique should prove useful for research in intra-operative single-stage surgery scenarios. To demonstrate the use of our method, we applied our method during real-time mapping of eloquent cortex during a single-stage surgery. The results demonstrated that our method can be applied intra-operatively in the absence of post-operative imaging to acquire ECoG signals that can be valuable for neuroscientific investigations.
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Affiliation(s)
- Disha Gupta
- Dept. of Neurology, Albany Medical College, Albany, NY, USA
- Neural Injury and Repair, Wadsworth Center, New York State Dept. of Health, Albany, NY, USA
- Early Brain Injury and Motor Recovery Lab, Burke-Cornell Medical Research Institute, White Plains, NY, USA
| | - N. Jeremy Hill
- Neural Injury and Repair, Wadsworth Center, New York State Dept. of Health, Albany, NY, USA
- Translational Neurological Research Laboratory, Helen Hayes Hospital, West Haverstraw, NY, USA
| | | | | | - Gerwin Schalk
- Dept. of Neurology, Albany Medical College, Albany, NY, USA
- Neural Injury and Repair, Wadsworth Center, New York State Dept. of Health, Albany, NY, USA
- Dept. of Neurosurgery, Washington University, St. Louis, MO, USA
- Dept. of Biomed. Eng., Rensselaer Polytechnic Institute, Troy, NY, USA
- Dept. of Biomed. Sci., State Univ. of New York at Albany, Albany, NY, USA
- Dept. of Elec. and Comp. Eng., Univ. of Texas at El Paso, El Paso, TX, USA
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Sohrabpour A, Lu Y, Kankirawatana P, Blount J, Kim H, He B. Effect of EEG electrode number on epileptic source localization in pediatric patients. Clin Neurophysiol 2014; 126:472-80. [PMID: 25088733 DOI: 10.1016/j.clinph.2014.05.038] [Citation(s) in RCA: 83] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2014] [Revised: 05/14/2014] [Accepted: 05/19/2014] [Indexed: 11/18/2022]
Abstract
OBJECTIVE To investigate the relationship between EEG source localization and the number of scalp EEG recording channels. METHODS 128 EEG channel recordings of 5 pediatric patients with medically intractable partial epilepsy were used to perform source localization of interictal spikes. The results were compared with surgical resection and intracranial recordings. Various electrode configurations were tested and a series of computer simulations based on a realistic head boundary element model were also performed in order to further validate the clinical findings. RESULTS The improvement seen in source localization substantially decreases as the number of electrodes increases. This finding was evaluated using the surgical resection, intracranial recordings and computer simulation. It was also shown in the simulation that increasing the electrode numbers could remedy the localization error of deep sources. A plateauing effect was seen in deep and superficial sources with further increasing the electrode number. CONCLUSION The source localization is improved when electrode numbers increase, but the absolute improvement in accuracy decreases with increasing electrode number. SIGNIFICANCE Increasing the electrode number helps decrease localization error and thus can more ably assist the physician to better plan for surgical procedures.
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Affiliation(s)
- Abbas Sohrabpour
- Department of Biomedical Engineering, University of Minnesota, Minneapolis, MN, USA
| | - Yunfeng Lu
- Department of Biomedical Engineering, University of Minnesota, Minneapolis, MN, USA
| | - Pongkiat Kankirawatana
- Division of Pediatric Neurology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Jeffrey Blount
- Division of Neurosurgery, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Hyunmi Kim
- Division of Pediatric Neurology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Bin He
- Department of Biomedical Engineering, University of Minnesota, Minneapolis, MN, USA; Institute for Engineering in Medicine, University of Minnesota, Minneapolis, MN, USA.
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Mascalchi M, Ginestroni A, Toschi N, Poggesi A, Cecchi P, Salvadori E, Tessa C, Cosottini M, De Stefano N, Pracucci G, Pantoni L, Inzitari D, Diciotti S. The burden of microstructural damage modulates cortical activation in elderly subjects with MCI and leuko-araiosis. A DTI and fMRI study. Hum Brain Mapp 2014; 35:819-30. [PMID: 23225611 PMCID: PMC6869323 DOI: 10.1002/hbm.22216] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2011] [Revised: 09/27/2012] [Accepted: 10/03/2012] [Indexed: 12/11/2022] Open
Abstract
The term leuko-araiosis (LA) describes a common chronic affection of the cerebral white matter (WM) in the elderly due to small vessel disease with variable clinical correlates. To explore whether severity of LA entails some adaptive reorganization in the cerebral cortex we evaluated with functional MRI (fMRI) the cortical activation pattern during a simple motor task in 60 subjects with mild cognitive impairment and moderate or severe (moderate-to-severe LA group, n = 46) and mild (mild LA group, n = 14) LA extension on visual rating. The microstructural damage associated with LA was measured on diffusion tensor data by computation of the mean diffusivity (MD) of the cerebral WM and by applying tract based spatial statistics (TBSS). Subjects were examined with fMRI during continuous tapping of the right dominant hand with task performance measurement. Moderate-to-severe LA group showed hyperactivation of left primary sensorimotor cortex (SM1) and right cerebellum. Regression analyses using the individual median of WM MD as explanatory variable revealed a posterior shift of activation within the left SM1 and hyperactivation of the left SMA and paracentral lobule and of the bilateral cerebellar crus. These data indicate that brain activation is modulated by increasing severity of LA with a local remapping within the SM1 and increased activity in ipsilateral nonprimary sensorimotor cortex and bilateral cerebellum. These potentially adaptive changes as well lack of contralateral cerebral hemisphere hyperactivation are in line with sparing of the U fibers and brainstem and cerebellar WM tracts and the emerging microstructual damage of the corpus callosum revealed by TBSS with increasing severity of LA.
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Affiliation(s)
- Mario Mascalchi
- Radiodiagnostic Section, Department of Clinical Physiopathology, University of Florence, Florence, Italy
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