1
|
Wu M, Concolato M, Sorger B, Yu Y, Li X, Luo B, Riecke L. Acoustic-electric trigeminal-nerve stimulation enhances functional connectivity in patients with disorders of consciousness. CNS Neurosci Ther 2024; 30:e14385. [PMID: 37525451 PMCID: PMC10928333 DOI: 10.1111/cns.14385] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Revised: 06/29/2023] [Accepted: 07/16/2023] [Indexed: 08/02/2023] Open
Abstract
AIM Disruption of functional brain connectivity is thought to underlie disorders of consciousness (DOC) and recovery of impaired connectivity is suggested as an indicator of consciousness restoration. We recently found that rhythmic acoustic-electric trigeminal-nerve stimulation (i.e., musical stimulation synchronized to electrical stimulation of the trigeminal nerve) in the gamma band can improve consciousness in patients with DOC. Here, we investigated whether these beneficial stimulation effects are mediated by alterations in functional connectivity. METHODS Sixty-three patients with DOC underwent 5 days of gamma, beta, or sham acoustic-electric trigeminal-nerve stimulation. Resting-state electroencephalography was measured before and after the stimulation and functional connectivity was assessed using phase-lag index (PLI). RESULTS We found that gamma stimulation induces an increase in gamma-band PLI. Further characterization revealed that the enhancing effect is (i) specific to the gamma band (as we observed no comparable change in beta-band PLI and no effect of beta-band acoustic-electric stimulation or sham stimulation), (ii) widely spread across the cortex, and (iii) accompanied by improvements in patients' auditory abilities. CONCLUSION These findings show that gamma acoustic-electric trigeminal-nerve stimulation can improve resting-state functional connectivity in the gamma band, which in turn may be linked to auditory abilities and/or consciousness restoration in DOC patients.
Collapse
Affiliation(s)
- Min Wu
- Department of Cognitive Neuroscience, Faculty of Psychology and NeuroscienceMaastricht UniversityMaastrichtThe Netherlands
| | - Marta Concolato
- Department of Cognitive Neuroscience, Faculty of Psychology and NeuroscienceMaastricht UniversityMaastrichtThe Netherlands
- Department of Developmental Psychology and SocializationUniversity of PadovaPadovaItaly
| | - Bettina Sorger
- Department of Cognitive Neuroscience, Faculty of Psychology and NeuroscienceMaastricht UniversityMaastrichtThe Netherlands
| | - Yamei Yu
- Department of Neurology and Brain Medical Centre, First Affiliated Hospital, School of MedicineZhejiang UniversityHangzhouChina
| | - Xiaoxia Li
- Department of Neurology and Brain Medical Centre, First Affiliated Hospital, School of MedicineZhejiang UniversityHangzhouChina
| | - Benyan Luo
- Department of Neurology and Brain Medical Centre, First Affiliated Hospital, School of MedicineZhejiang UniversityHangzhouChina
| | - Lars Riecke
- Department of Cognitive Neuroscience, Faculty of Psychology and NeuroscienceMaastricht UniversityMaastrichtThe Netherlands
| |
Collapse
|
2
|
Binder M, Papiernik J, Griskova-Bulanova I, Frycz S, Chojnacki B, Górska-Klimowska U. Diagnosing awareness in disorders of consciousness with gamma-band auditory responses. Front Hum Neurosci 2024; 17:1243051. [PMID: 38249572 PMCID: PMC10796678 DOI: 10.3389/fnhum.2023.1243051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2023] [Accepted: 11/28/2023] [Indexed: 01/23/2024] Open
Abstract
Introduction The prolonged disorders of consciousness (pDOC) describe a group of neurological conditions characterized by severe impairment of consciousness resulting from the injury of the central nervous system. As the behavioral diagnosis of pDOC remains challenging, the methods based on observing brain activity appear as promising alternatives. One of these methods is electroencephalography, which allows for noninvasive assessment of brain function. Methods In this study, we evaluated evoked auditory responses to the chirp-modulated auditory stimulation as a potential biomarker of awareness in pDOC. Chirp-modulated stimulation is based on the repetitive presentation of auditory stimuli with a changing frequency over time. Two protocols were tested: amplitude-modulated narrow-band chirps (frequency range 25-55 Hz) and click-based wide-band chirps (30-100 Hz). The studied pDOC patient group included 62 patients (19 females and 43 males, mean age 40.72 years) diagnosed with Coma Recovery Scale-Revised. Envelope-following responses to stimulation were examined using the intertrial phase clustering coefficient. Results For both types of stimulation, the strength of the response in the low-gamma range (around 40 Hz) was related to the diagnosis of pDOC. Patients diagnosed with unresponsive wakefulness syndrome exhibited diminished responses, while more favorable diagnoses, suggesting awareness (minimally conscious state or emergence from the minimally conscious state), showed elevated responses. The variations in the integrity of the auditory pathway and the etiology of brain injury altered the observed response strength. Narrow-band stimulation yielded a more systematic relationship between low-gamma response and pDOC diagnosis. Discussion The results suggest the potential role of low gamma-band responses to chirp-modulated stimulation as the supportive diagnostic tool to detect awareness in the pDOC patient group.
Collapse
Affiliation(s)
- Marek Binder
- Institute of Psychology, Jagiellonian University, Kraków, Poland
| | - Julia Papiernik
- Institute of Psychology, Jagiellonian University, Kraków, Poland
- Doctoral School in the Social Sciences, Jagiellonian University, Kraków, Poland
| | | | - Sandra Frycz
- Institute of Psychology, Jagiellonian University, Kraków, Poland
- Doctoral School in the Social Sciences, Jagiellonian University, Kraków, Poland
| | - Bartłomiej Chojnacki
- Department of Mechanics and Vibroacoustics, Faculty of Mechanical Engineering and Robotics, AGH University of Krakow, Kraków, Poland
| | | |
Collapse
|
3
|
Altıntop ÇG, Latifoğlu F, Akın AK, Ülgey A. Quantitative Electroencephalography Analysis for Improved Assessment of Consciousness Levels in Deep Coma Patients Using a Proposed Stimulus Stage. Diagnostics (Basel) 2023; 13:diagnostics13081383. [PMID: 37189484 DOI: 10.3390/diagnostics13081383] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2023] [Revised: 04/06/2023] [Accepted: 04/06/2023] [Indexed: 05/17/2023] Open
Abstract
"Coma" is defined as an inability to obey commands, to speak, or to open the eyes. So, a coma is a state of unarousable unconsciousness. In a clinical setting, the ability to respond to a command is often used to infer consciousness. Evaluation of the patient's level of consciousness (LeOC) is important for neurological evaluation. The Glasgow Coma Scale (GCS) is the most widely used and popular scoring system for neurological evaluation and is used to assess a patient's level of consciousness. The aim of this study is the evaluation of GCSs with an objective approach based on numerical results. So, EEG signals were recorded from 39 patients in a coma state with a new procedure proposed by us in a deep coma state (GCS: between 3 and 8). The EEG signals were divided into four sub-bands as alpha, beta, delta, and theta, and their power spectral density was calculated. As a result of power spectral analysis, 10 different features were extracted from EEG signals in the time and frequency domains. The features were statistically analyzed to differentiate the different LeOC and to relate with the GCS. Additionally, some machine learning algorithms have been used to measure the performance of the features for distinguishing patients with different GCSs in a deep coma. This study demonstrated that GCS 3 and GCS 8 patients were classified from other levels of consciousness in terms of decreased theta activity. To the best of our knowledge, this is the first study to classify patients in a deep coma (GCS between 3 and 8) with 96.44% classification performance.
Collapse
Affiliation(s)
| | - Fatma Latifoğlu
- Department of Biomedical Engineering, Erciyes University, Kayseri 38039, Turkey
| | - Aynur Karayol Akın
- Department of Anesthesiology and Reanimation, Erciyes University, Kayseri 38039, Turkey
| | - Ayşe Ülgey
- Department of Anesthesiology and Reanimation, Erciyes University, Kayseri 38039, Turkey
| |
Collapse
|
4
|
Bouchereau E, Marchi A, Hermann B, Pruvost-Robieux E, Guinard E, Legouy C, Schimpf C, Mazeraud A, Baron JC, Ramdani C, Gavaret M, Sharshar T, Turc G. Quantitative analysis of early-stage EEG reactivity predicts awakening and recovery of consciousness in patients with severe brain injury. Br J Anaesth 2023; 130:e225-e232. [PMID: 36243578 DOI: 10.1016/j.bja.2022.09.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2022] [Revised: 09/06/2022] [Accepted: 09/09/2022] [Indexed: 01/25/2023] Open
Abstract
BACKGROUND Decisions of withdrawal of life-sustaining therapy for patients with severe brain injury are often based on prognostic evaluations such as analysis of electroencephalography (EEG) reactivity (EEG-R). However, EEG-R usually relies on visual assessment, which requires neurophysiological expertise and is prone to inter-rater variability. We hypothesised that quantitative analysis of EEG-R obtained 3 days after patient admission can identify new markers of subsequent awakening and consciousness recovery. METHODS In this prospective observational study of patients with severe brain injury requiring mechanical ventilation, quantitative EEG-R was assessed using standard 11-lead EEG with frequency-based (power spectral density) and functional connectivity-based (phase-lag index) analyses. Associations between awakening in the intensive care unit (ICU) and reactivity to auditory and nociceptive stimulations were assessed with logistic regression. Secondary outcomes included in-ICU mortality and 3-month Coma Recovery Scale-Revised (CRS-R) score. RESULTS Of 116 patients, 86 (74%) awoke in the ICU. Among quantitative EEG-R markers, variation in phase-lag index connectivity in the delta frequency band after noise stimulation was associated with awakening (adjusted odds ratio=0.89, 95% confidence interval: 0.81-0.97, P=0.02 corrected for multiple tests), independently of age, baseline severity, and sedation. This new marker was independently associated with improved 3-month CRS-R (adjusted β=-0.16, standard error 0.075, P=0.048), but not with mortality (adjusted odds ratio=1.08, 95% CI: 0.99-1.18, P=0.10). CONCLUSIONS An early-stage quantitative EEG-R marker was independently associated with awakening and 3-month level of consciousness in patients with severe brain injury. This promising marker based on functional connectivity will need external validation before potential integration into a multimodal prognostic model.
Collapse
Affiliation(s)
- Eléonore Bouchereau
- Anaesthesiology and ICU Department, Sainte Anne Hospital, Paris, France; Institute of Psychiatry and Neurosciences of Paris (IPNP), INSERM U1266, Paris, France.
| | - Angela Marchi
- Epileptology and Cerebral Rhythmology Department, APHM, Timone Hospital, Marseille, France
| | - Bertrand Hermann
- ICU Department, Hôpital Européen Georges Pompidou, Paris, France; Institut du Cerveau et de la Moelle épinière - ICM, Paris, France; Université Paris Cité, Paris, France
| | - Estelle Pruvost-Robieux
- Institute of Psychiatry and Neurosciences of Paris (IPNP), INSERM U1266, Paris, France; Université Paris Cité, Paris, France; Neurophysiology Department, Sainte Anne Hospital, Paris, France
| | - Eléonore Guinard
- Institute of Psychiatry and Neurosciences of Paris (IPNP), INSERM U1266, Paris, France; Université Paris Cité, Paris, France; Neurophysiology Department, Sainte Anne Hospital, Paris, France
| | - Camille Legouy
- Anaesthesiology and ICU Department, Sainte Anne Hospital, Paris, France
| | - Caroline Schimpf
- Anaesthesiology and ICU Department, Sainte Anne Hospital, Paris, France
| | - Aurélien Mazeraud
- Anaesthesiology and ICU Department, Sainte Anne Hospital, Paris, France; Université Paris Cité, Paris, France
| | - Jean-Claude Baron
- Institute of Psychiatry and Neurosciences of Paris (IPNP), INSERM U1266, Paris, France; Université Paris Cité, Paris, France; Neurology Department, GHU Paris Psychiatry and Neurosciences, Sainte Anne Hospital, Paris, France; FHU NeuroVasc, Paris, France
| | - Céline Ramdani
- Institut de Recherche Biomédicale des Armées (IRBA), Brétigny-sur-Orge, France
| | - Martine Gavaret
- Institute of Psychiatry and Neurosciences of Paris (IPNP), INSERM U1266, Paris, France; Université Paris Cité, Paris, France; Neurophysiology Department, Sainte Anne Hospital, Paris, France; FHU NeuroVasc, Paris, France
| | - Tarek Sharshar
- Anaesthesiology and ICU Department, Sainte Anne Hospital, Paris, France; Institute of Psychiatry and Neurosciences of Paris (IPNP), INSERM U1266, Paris, France; Université Paris Cité, Paris, France; FHU NeuroVasc, Paris, France
| | - Guillaume Turc
- Institute of Psychiatry and Neurosciences of Paris (IPNP), INSERM U1266, Paris, France; Université Paris Cité, Paris, France; Neurology Department, GHU Paris Psychiatry and Neurosciences, Sainte Anne Hospital, Paris, France; FHU NeuroVasc, Paris, France
| |
Collapse
|
5
|
Yu J, Wu Y, Wu B, Xu C, Cai J, Wen X, Meng F, Zhang L, He F, Hong L, Gao J, Li J, Yu J, Luo B. Sleep patterns correlates with the efficacy of tDCS on post-stroke patients with prolonged disorders of consciousness. J Transl Med 2022; 20:601. [PMID: 36522680 PMCID: PMC9756665 DOI: 10.1186/s12967-022-03710-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Accepted: 10/18/2022] [Indexed: 12/23/2022] Open
Abstract
BACKGROUND The subclassification of prolonged disorders of consciousness (DoC) based on sleep patterns is important for the evaluation and treatment of the disease. This study evaluates the correlation between polysomnographic patterns and the efficacy of transcranial direct current stimulation (tDCS) in patients with prolonged DoC due to stroke. METHODS In total, 33 patients in the vegetative state (VS) with sleep cycles or without sleep cycles were randomly assigned to either active or sham tDCS groups. Polysomnography was used to monitor sleep changes before and after intervention. Additionally, clinical scale scores and electroencephalogram (EEG) analysis were performed before and after intervention to evaluate the efficacy of tDCS on the patients subclassified according to their sleep patterns. RESULTS The results suggest that tDCS improved the sleep structure, significantly prolonged total sleep time (TST) (95%CI: 14.387-283.527, P = 0.013) and NREM sleep stage 2 (95%CI: 3.157-246.165, P = 0.040) of the VS patients with sleep cycles. It also significantly enhanced brain function of patients with sleep cycles, which were reflected by the increased clinical scores (95%CI: 0.340-3.440, P < 0.001), the EEG powers and functional connectivity in the brain and the 6-month prognosis. Moreover, the changes in NREM sleep stage 2 had a significant positive correlation with each index of the β band. CONCLUSION This study reveals the importance of sleep patterns in the prognosis and treatment of prolonged DoC and provides new evidence for the efficacy of tDCS in post-stroke patients with VS patients subclassified by sleep pattern. Trial registration URL: https://www. CLINICALTRIALS gov . Unique identifier: NCT03809936. Registered 18 January 2019.
Collapse
Affiliation(s)
- Jie Yu
- grid.452661.20000 0004 1803 6319Department of Neurology, First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, 310003 Zhejiang China
| | - Yuehao Wu
- grid.452661.20000 0004 1803 6319Department of Neurology, First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, 310003 Zhejiang China ,Department of Neurology, First People’s Hospital of Linping District, Hangzhou, 310003 Zhejiang China
| | - Biwen Wu
- grid.415999.90000 0004 1798 9361Center for Sleep Medicine, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, 310003 China
| | - Chuan Xu
- grid.452661.20000 0004 1803 6319Department of Neurology, First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, 310003 Zhejiang China
| | - Jiaye Cai
- grid.415999.90000 0004 1798 9361Center for Sleep Medicine, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, 310003 China
| | - Xinrui Wen
- grid.452661.20000 0004 1803 6319Department of Neurology, First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, 310003 Zhejiang China
| | - Fanxia Meng
- grid.452661.20000 0004 1803 6319Department of Neurology, First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, 310003 Zhejiang China
| | - Li Zhang
- grid.417401.70000 0004 1798 6507Rehabilitation Medicine Center, Department of Rehabilitation Medicine, Zhejiang Provincial People’s Hospital, Affiliated People’s Hospital of Hangzhou Medical College, Hangzhou, Zhejiang China
| | - Fangping He
- grid.452661.20000 0004 1803 6319Department of Neurology, First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, 310003 Zhejiang China
| | - Lirong Hong
- Department of Rehabilitation, Hangzhou Hospital of Zhejiang Armed Police Corps, Hangzhou, 310051 China
| | - Jian Gao
- Department of Rehabilitation, Hangzhou Mingzhou Brain Rehabilitation Hospital, Hangzhou, 311215 China
| | - Jingqi Li
- Department of Rehabilitation, Hangzhou Mingzhou Brain Rehabilitation Hospital, Hangzhou, 311215 China
| | - Jintai Yu
- grid.411405.50000 0004 1757 8861Department of Neurology and Institute of Neurology, Huashan Hospital, Shanghai Medical College, Fudan University, Shanghai, 200031 China
| | - Benyan Luo
- grid.452661.20000 0004 1803 6319Department of Neurology, First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, 310003 Zhejiang China
| |
Collapse
|
6
|
Wu M, Luo B, Yu Y, Li X, Gao J, Li J, Sorger B, Riecke L. Rhythmic musical-electrical trigeminal nerve stimulation improves impaired consciousness. Neuroimage Clin 2022; 36:103170. [PMID: 36063757 PMCID: PMC9460811 DOI: 10.1016/j.nicl.2022.103170] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2022] [Revised: 07/27/2022] [Accepted: 08/23/2022] [Indexed: 12/14/2022]
Abstract
Accumulating evidence shows that consciousness is linked to neural oscillations in the thalamocortical system, suggesting that deficits in these oscillations may underlie disorders of consciousness (DOC). However, patient-friendly non-invasive treatments targeting this functional anomaly are still missing and the therapeutic value of oscillation restoration has remained unclear. We propose a novel approach that aims to restore DOC patients' thalamocortical oscillations by combining rhythmic trigeminal-nerve stimulation with comodulated musical stimulation ("musical-electrical TNS"). In a double-blind, placebo-controlled, parallel-group study, we recruited 63 patients with DOC and randomly assigned them to groups receiving gamma, beta, or sham musical-electrical TNS. The stimulation was applied for 40 min on five consecutive days. We measured patients' consciousness before and after the stimulation using behavioral indicators and neural responses to rhythmic auditory speech. We further assessed their outcomes one year later. We found that musical-electrical TNS reliably lead to improvements in consciousness and oscillatory brain activity at the stimulation frequency: 43.5 % of patients in the gamma group and 25 % of patients in the beta group showed an improvement of their diagnosis after being treated with the stimulation. This group of benefitting patients still showed more positive outcomes one year later. Moreover, patients with stronger behavioral benefits showed stronger improvements in oscillatory brain activity. These findings suggest that brain oscillations contribute to consciousness and that musical-electrical TNS may serve as a promising approach to improve consciousness and predict long-term outcomes in patients with DOC.
Collapse
Affiliation(s)
- Min Wu
- Department of Neurology & Brain Medical Centre, First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China,Department of Cognitive Neuroscience, Faculty of Psychology and Neuroscience, Maastricht University, Maastricht, Netherlands
| | - Benyan Luo
- Department of Neurology & Brain Medical Centre, First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China,Corresponding author.
| | - Yamei Yu
- Department of Neurology & Brain Medical Centre, First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Xiaoxia Li
- Department of Neurology & Brain Medical Centre, First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Jian Gao
- Hangzhou Mingzhou Brain Rehabilitation Hospital, Hangzhou, China
| | - Jingqi Li
- Hangzhou Mingzhou Brain Rehabilitation Hospital, Hangzhou, China
| | - Bettina Sorger
- Department of Cognitive Neuroscience, Faculty of Psychology and Neuroscience, Maastricht University, Maastricht, Netherlands
| | - Lars Riecke
- Department of Cognitive Neuroscience, Faculty of Psychology and Neuroscience, Maastricht University, Maastricht, Netherlands
| |
Collapse
|
7
|
Liuzzi P, De Bellis F, Magliacano A, Estraneo A, Mannini A. Consciousness-Domain Index: a data-driven clustering-based consciousness labeling. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2022; 2022:1062-1065. [PMID: 36086422 DOI: 10.1109/embc48229.2022.9871151] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Assessing consciousness results in one of the most complex neurological diagnosis. Even more complex and uncertain is prognosticating on consciousness recovery. Currently, consciousness is assessed by using a six-items scale, the Coma Recovery Scale-Revised. Namely, scores on the sub-items can individually assign or not a specific level of consciousness to a patient. In our work, by using solely the six sub-items of the CRS-R, we implemented a clustering algorithm labeling patients with the Consciousness-Domains Index (CDI) starting from a dataset of 190 patients with a Disorder of Consciousness (DoC). Then, the CDI is compared with the clinical state at admission and at six months via univariate analysis. The number of clusters best dividing the groups resulted equal to two and the most influencing sub-items resulted the visual and motor one. The CDI closely resembles the clinical state at admission (CSA) (Cohen's k=0.85). On the other hand, when comparing CDI and CSA, a net improvement was found in the prognostic power of the neurological outcome at six months, targeted as presence/absence of a DoC ( ). Data-driven techniques pave the way for automated and model-based search of prognostic factors, together with the use of such prognostic factors in multivariate prognostic models. Future works will address the external validation of the CDI, together with the inclusion of the CDI in a multivariate supervised model, in order to assess the true potential of such novel index. Clinical Relevance- A completely data-driven index was derived from a clustering of CRS-R sub-items. It correlates with the neurological outcome at six months better than the state of consciousness at admission.
Collapse
|
8
|
Altıntop ÇG, Latifoğlu F, Akın AK, Bayram A, Çiftçi M. Classification of Depth of Coma Using Complexity Measures and Nonlinear Features of Electroencephalogram Signals. Int J Neural Syst 2022; 32:2250018. [PMID: 35300584 DOI: 10.1142/s0129065722500186] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
In recent years, some electrophysiological analysis methods of consciousness have been proposed. Most of these studies are based on visual interpretation or statistical analysis, and there is hardly any work classifying the level of consciousness in a deep coma. In this study, we perform an analysis of electroencephalography complexity measures by quantifying features efficiency in differentiating patients in different consciousness levels. Several measures of complexity have been proposed to quantify the complexity of signals. Our aim is to lay the foundation of a system that will objectively define the level of consciousness by performing a complexity analysis of Electroencephalogram (EEG) signals. Therefore, a nonlinear analysis of EEG signals obtained with a recording scheme proposed by us from 39 patients with Glasgow Coma Scale (GCS) between 3 and 8 was performed. Various entropy values (approximate entropy, permutation entropy, etc.) obtained from different algorithms, Hjorth parameters, Lempel-Ziv complexity and Kolmogorov complexity values were extracted from the signals as features. The features were analyzed statistically and the success of features in classifying different levels of consciousness was measured by various classifiers. Consequently, levels of consciousness in deep coma (GCS between 3 and 8) were classified with an accuracy of 90.3%. To the authors' best knowledge, this is the first demonstration of the discriminative nonlinear features extracted from tactile and auditory stimuli EEG signals in distinguishing different GCSs of comatose patients.
Collapse
Affiliation(s)
| | - Fatma Latifoğlu
- Department of Biomedical Engineering, Erciyes University, Turkey
| | - Aynur Karayol Akın
- Department of Anesthesiology and Reanimation, Erciyes University, Turkey
| | - Adnan Bayram
- Department of Anesthesiology and Reanimation, Erciyes University, Turkey
| | - Murat Çiftçi
- Department of Neurosurgery, Erciyes University, Turkey
| |
Collapse
|
9
|
Complementary roles of neural synchrony and complexity for indexing consciousness and chances of surviving in acute coma. Neuroimage 2021; 245:118638. [PMID: 34624502 DOI: 10.1016/j.neuroimage.2021.118638] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2021] [Revised: 09/28/2021] [Accepted: 10/05/2021] [Indexed: 11/23/2022] Open
Abstract
An open challenge in consciousness research is understanding how neural functions are altered by pathological loss of consciousness. To maintain consciousness, the brain needs synchronized communication of information across brain regions, and sufficient complexity in neural activity. Coordination of brain activity, typically indexed through measures of neural synchrony, has been shown to decrease when consciousness is lost and to reflect the clinical state of patients with disorders of consciousness. Moreover, when consciousness is lost, neural activity loses complexity, while the levels of neural noise, indexed by the slope of the electroencephalography (EEG) spectral exponent decrease. Although these properties have been well investigated in resting state activity, it remains unknown whether the sensory processing network, which has been shown to be preserved in coma, suffers from a loss of synchronization or information content. Here, we focused on acute coma and hypothesized that neural synchrony in response to auditory stimuli would reflect coma severity, while complexity, or neural noise, would reflect the presence or loss of consciousness. Results showed that neural synchrony of EEG signals was stronger for survivors than non-survivors and predictive of patients' outcome, but indistinguishable between survivors and healthy controls. Measures of neural complexity and neural noise were not informative of patients' outcome and had high or low values for patients compared to controls. Our results suggest different roles for neural synchrony and complexity in acute coma. Synchrony represents a precondition for consciousness, while complexity needs an equilibrium between high or low values to support conscious cognition.
Collapse
|
10
|
Heine L, Corneyllie A, Gobert F, Luauté J, Lavandier M, Perrin F. Virtually spatialized sounds enhance auditory processing in healthy participants and patients with a disorder of consciousness. Sci Rep 2021; 11:13702. [PMID: 34211035 PMCID: PMC8249625 DOI: 10.1038/s41598-021-93151-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2020] [Accepted: 06/22/2021] [Indexed: 11/14/2022] Open
Abstract
Neuroscientific and clinical studies on auditory perception often use headphones to limit sound interference. In these conditions, sounds are perceived as internalized because they lack the sound-attributes that normally occur with a sound produced from a point in space around the listener. Without the spatial attention mechanisms that occur with localized sounds, auditory functional assessments could thus be underestimated. We hypothesize that adding virtually externalization and localization cues to sounds through headphones enhance sound discrimination in both healthy participants and patients with a disorder of consciousness (DOC). Hd-EEG was analyzed in 14 healthy participants and 18 patients while they listened to self-relevant and irrelevant stimuli in two forms: diotic (classic sound presentation with an "internalized" feeling) and convolved with a binaural room impulse response (to create an "externalized" feeling). Convolution enhanced the brains' discriminative response as well as the processing of irrelevant sounds itself, in both healthy participants and DOC patients. For the healthy participants, these effects could be associated with enhanced activation of both the dorsal (where/how) and ventral (what) auditory streams, suggesting that spatial attributes support speech discrimination. Thus, virtually spatialized sounds might "call attention to the outside world" and improve the sensitivity of assessment of brain function in DOC patients.
Collapse
Affiliation(s)
- Lizette Heine
- Audition Cognition and Psychoacoustics Team, Lyon Neuroscience Research Center, UCBL, INSERM U1028, CNRS UMR5292, Centre Hospitalier Le Vinatier, Bâtiment 462, Neurocampus Michel Jouvet, 95 Boulevard Pinel, Bron Cedex, 69675, Lyon, France
- Laboratoire de Tribologie et Dynamique des Systèmes UMR 5513, ENTPE, University of Lyon, Rue Maurice Audin, 69518, Vaulx-en-Velin Cedex, France
| | - Alexandra Corneyllie
- Audition Cognition and Psychoacoustics Team, Lyon Neuroscience Research Center, UCBL, INSERM U1028, CNRS UMR5292, Centre Hospitalier Le Vinatier, Bâtiment 462, Neurocampus Michel Jouvet, 95 Boulevard Pinel, Bron Cedex, 69675, Lyon, France
| | - Florent Gobert
- Audition Cognition and Psychoacoustics Team, Lyon Neuroscience Research Center, UCBL, INSERM U1028, CNRS UMR5292, Centre Hospitalier Le Vinatier, Bâtiment 462, Neurocampus Michel Jouvet, 95 Boulevard Pinel, Bron Cedex, 69675, Lyon, France
- Trajectoires Team, Lyon Neuroscience Research Center, UCBL, INSERM U1028, CNRS UMR5292, Centre Hospitalier Le Vinatier, Lyon, France
| | - Jacques Luauté
- Service de Médecine Physique et de Réadaptation, Rééducation Neurologique, Hôpital Henry-Gabrielle, CHU de Lyon, 69230, Saint-Genis-Laval, France
- Trajectoires Team, Lyon Neuroscience Research Center, UCBL, INSERM U1028, CNRS UMR5292, Centre Hospitalier Le Vinatier, Lyon, France
| | - Mathieu Lavandier
- Laboratoire de Tribologie et Dynamique des Systèmes UMR 5513, ENTPE, University of Lyon, Rue Maurice Audin, 69518, Vaulx-en-Velin Cedex, France
| | - Fabien Perrin
- Audition Cognition and Psychoacoustics Team, Lyon Neuroscience Research Center, UCBL, INSERM U1028, CNRS UMR5292, Centre Hospitalier Le Vinatier, Bâtiment 462, Neurocampus Michel Jouvet, 95 Boulevard Pinel, Bron Cedex, 69675, Lyon, France.
| |
Collapse
|
11
|
Individual Resonant Frequencies at Low-Gamma Range and Cognitive Processing Speed. J Pers Med 2021; 11:jpm11060453. [PMID: 34071027 PMCID: PMC8224604 DOI: 10.3390/jpm11060453] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Revised: 05/03/2021] [Accepted: 05/21/2021] [Indexed: 02/04/2023] Open
Abstract
Brain electrophysiological activity within the low gamma frequencies (30–80 Hz) has been proposed to reflect information encoding and transfer processes. The 40-Hz auditory steady-state response (40-Hz ASSR) is frequently discussed in relation to changed cognitive processing in neuropsychiatric disorders. However, the relationship between ASSRs and cognitive functioning still remains unclear. Most of the studies assessed the single frequency ASSR, while the individual resonance frequency in the gamma range (30–60 Hz), also called individual gamma frequency (IGF), has received limited attention thus far. Nevertheless, IGF potentially might better reflect individual network characteristics than standardly utilized 40-Hz ASSRs. Here, we focused on the processing speed across different types of cognitive tasks and explored its relationship with responses at 40 Hz and at IGFs in an attempt to uncover how IGFs relate to certain aspects of cognitive functioning. We show that gamma activity is related to the performance speed on complex cognitive task tapping planning and problem solving, both when responses at 40 Hz and at IGFs were evaluated. With the individualized approach, the observed associations were found to be somewhat stronger, and the association seemed to primarily reflect individual differences in higher-order cognitive processing. These findings have important implications for the interpretation of gamma activity in neuropsychiatric disorders.
Collapse
|
12
|
Xu C, Zou J, He F, Wen X, Li J, Gao J, Ding N, Luo B. Neural Tracking of Sound Rhythms Correlates With Diagnosis, Severity, and Prognosis of Disorders of Consciousness. Front Neurosci 2021; 15:646543. [PMID: 33994924 PMCID: PMC8113690 DOI: 10.3389/fnins.2021.646543] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2020] [Accepted: 03/19/2021] [Indexed: 12/03/2022] Open
Abstract
Effective diagnosis and prognosis of patients with disorders of consciousness (DOC) provides a basis for family counseling, decision-making, and the design of rehabilitation programs. However, effective and objective bedside evaluation is a challenging problem. In this study, we explored electroencephalography (EEG) response tracking sound rhythms as potential neural markers for DOC evaluation. We analyzed the responses to natural speech and tones modulated at 2 and 41 Hz. At the population level, patients with positive outcomes (DOC-P) showed higher cortical synchronization to modulated tones at 41 Hz compared with patients with negative outcomes (DOC-N). At the individual level, phase coherence to modulated tones at 41 Hz was significantly correlated with Coma Recovery Scale-Revised (CRS-R) and Glasgow Outcome Scale-Extended (GOS-E) scores. Furthermore, SVM classifiers, trained using phase coherences in higher frequency bands or combination of the low frequency aSSR and speech tracking responses, performed very well in diagnosis and prognosis of DOC. These findings show that EEG response to auditory rhythms is a potential tool for diagnosis, severity, and prognosis of DOC.
Collapse
Affiliation(s)
- Chuan Xu
- Department of Neurology, First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Jiajie Zou
- Key Laboratory for Biomedical Engineering of Ministry of Education, College of Biomedical Engineering and Instrument Sciences, Zhejiang University, Hangzhou, China.,Research Center for Advanced Artificial Intelligence Theory Zhejiang Lab, Hangzhou, China
| | - Fangping He
- Department of Neurology, First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Xinrui Wen
- Department of Neurology, First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Jingqi Li
- Department of Rehabilitation, Hangzhou Mingzhou Brain Rehabilitation Hospital, Hangzhou, China
| | - Jian Gao
- Department of Rehabilitation, Hangzhou Mingzhou Brain Rehabilitation Hospital, Hangzhou, China
| | - Nai Ding
- Key Laboratory for Biomedical Engineering of Ministry of Education, College of Biomedical Engineering and Instrument Sciences, Zhejiang University, Hangzhou, China.,Research Center for Advanced Artificial Intelligence Theory Zhejiang Lab, Hangzhou, China
| | - Benyan Luo
- Department of Neurology, First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| |
Collapse
|
13
|
Griskova-Bulanova I, Voicikas A, Dapsys K, Melynyte S, Andruskevicius S, Pipinis E. Envelope Following Response to 440 Hz Carrier Chirp-Modulated Tones Show Clinically Relevant Changes in Schizophrenia. Brain Sci 2020; 11:brainsci11010022. [PMID: 33375449 PMCID: PMC7824599 DOI: 10.3390/brainsci11010022] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2020] [Revised: 12/20/2020] [Accepted: 12/24/2020] [Indexed: 12/16/2022] Open
Abstract
The 40 Hz auditory steady-state response (ASSR) impairment is suggested as an electrophysiological biomarker of schizophrenia; however, existing data also points to the deficiency of low and high frequency ASSR responses. In order to obtain the full picture of potential impairment in schizophrenia, it is important to test responses at different frequencies. The current study aims to evaluate a wide frequency range (1-120 Hz) in response to brief low-frequency carrier chirp-modulated tones in a group of patients with schizophrenia. The EEG-derived envelope following responses (EFRs) were obtained in a group of male patients with schizophrenia (N = 18) and matched controls (N = 18). While subjects were watching silent movies, 440 Hz carrier chirp-modulated at 1-120 Hz tones were presented. Phase-locking index and evoked amplitude in response to stimulation were assessed and compared on point-to-point basis. The peak frequency of the low gamma response was estimated. Measures were correlated with psychopathology-positive, negative, total scores of the Positive and Negative Syndrome Scale (PANSS), and hallucination subscale scores. In comparison to controls, patients showed (1) reduced power of theta-beta (4-18 Hz) responses, (2) intact but slower low gamma (30-60 Hz), and (3) reduced high gamma (95-120 Hz) responses. No correlation survived the Bonferroni correction, but a sign of positive association between low gamma phase-locking and the prevalence of hallucinations, and a sign of negative association between high gamma phase-locking and the total PANSS scores were observed. Brain networks showed impaired capabilities to generate EFRs at different frequencies in schizophrenia; moreover, even when responses of patients did not significantly differ from controls on the group level, they still showed potentially clinically relevant variability.
Collapse
Affiliation(s)
- Inga Griskova-Bulanova
- Institute of Biosciences, Life Sciences Centre, Vilnius University, Saulėtekio av. 7, LT-10257 Vilnius, Lithuania; (K.D.); (S.M.); (E.P.)
- Correspondence: ; Tel.: +370-67110954
| | - Aleksandras Voicikas
- Vilnius Republican Psychiatric Hospital, Parko str. 21, LT-11205 Vilnius, Lithuania; (A.V.); (S.A.)
| | - Kastytis Dapsys
- Institute of Biosciences, Life Sciences Centre, Vilnius University, Saulėtekio av. 7, LT-10257 Vilnius, Lithuania; (K.D.); (S.M.); (E.P.)
- Vilnius Republican Psychiatric Hospital, Parko str. 21, LT-11205 Vilnius, Lithuania; (A.V.); (S.A.)
| | - Sigita Melynyte
- Institute of Biosciences, Life Sciences Centre, Vilnius University, Saulėtekio av. 7, LT-10257 Vilnius, Lithuania; (K.D.); (S.M.); (E.P.)
| | - Sergejus Andruskevicius
- Vilnius Republican Psychiatric Hospital, Parko str. 21, LT-11205 Vilnius, Lithuania; (A.V.); (S.A.)
- Institute of Psychology, Mykolas Romeris University, Ateities str. 20, LT-08303 Vilnius, Lithuania
| | - Evaldas Pipinis
- Institute of Biosciences, Life Sciences Centre, Vilnius University, Saulėtekio av. 7, LT-10257 Vilnius, Lithuania; (K.D.); (S.M.); (E.P.)
| |
Collapse
|
14
|
Górska U, Rupp A, Celikel T, Englitz B. Assessing the state of consciousness for individual patients using complex, statistical stimuli. NEUROIMAGE-CLINICAL 2020; 29:102471. [PMID: 33388561 PMCID: PMC7788231 DOI: 10.1016/j.nicl.2020.102471] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/20/2019] [Revised: 09/29/2020] [Accepted: 10/14/2020] [Indexed: 12/01/2022]
Abstract
Patients with prolonged disorders of consciousness (PDOC) are often unable to communicate their state of consciousness. Determining the latter is essential for the patient's care and prospects of recovery. Auditory stimulation in combination with neural recordings is a promising technique towards an objective assessment of conscious awareness. Here, we investigated the potential of complex, acoustic stimuli to elicit EEG responses suitable for classifying multiple subject groups, from unconscious to responding. We presented naturalistic auditory textures with unexpectedly changing statistics to human listeners. Awake, active listeners were asked to indicate the change by button press, while all other groups (awake passive, asleep, minimally conscious state (MCS), and unresponsive wakefulness syndrome (UWS)) listened passively. We quantified the evoked potential at stimulus onset and change in stimulus statistics, as well as the complexity of neural response during the change of stimulus statistics. On the group level, onset and change potentials classified patients and healthy controls successfully but failed to differentiate between the UWS and MCS groups. Conversely, the Lempel-Ziv complexity of the scalp-level potential allowed reliable differentiation between UWS and MCS even for individual subjects, when compared with the clinical assessment aligned to the EEG measurements. The accuracy appears to improve further when taking the latest available clinical diagnosis into account. In summary, EEG signal complexity during onset and changes in complex acoustic stimuli provides an objective criterion for distinguishing states of consciousness in clinical patients. These results suggest EEG-recordings as a cost-effective tool to choose appropriate treatments for non-responsive PDOC patients.
Collapse
Affiliation(s)
- U Górska
- Computational Neuroscience Laboratory, Department of Neurophysiology, Donders Institute, Radboud University Nijmegen, The Netherlands; Psychophysiology Laboratory, Institute of Psychology, Jagiellonian University, Krakow, Poland; Smoluchowski Institute of Physics, Jagiellonian University, Krakow, Poland.
| | - A Rupp
- Section of Biomagnetism, Department of Neurology, University of Heidelberg, Heidelberg, Germany
| | - T Celikel
- Computational Neuroscience Laboratory, Department of Neurophysiology, Donders Institute, Radboud University Nijmegen, The Netherlands
| | - B Englitz
- Computational Neuroscience Laboratory, Department of Neurophysiology, Donders Institute, Radboud University Nijmegen, The Netherlands.
| |
Collapse
|
15
|
Binder M, Górska U, Pipinis E, Voicikas A, Griskova-Bulanova I. Auditory steady-state response to chirp-modulated tones: A pilot study in patients with disorders of consciousness. NEUROIMAGE-CLINICAL 2020; 27:102261. [PMID: 32388346 PMCID: PMC7215243 DOI: 10.1016/j.nicl.2020.102261] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/25/2019] [Revised: 03/23/2020] [Accepted: 03/29/2020] [Indexed: 12/17/2022]
Abstract
Chirp-evoked responses were evaluated in patients with disorders of consciousness. PLI estimates in 38–42 Hz window positively correlated with the CRS-R total score. Gamma-range evoked activity may indicate the integrity of thalamocortical networks.
Objective Due to the problems with behavioral diagnosis of patients with prolonged DOC (disorders of consciousness), complementary approaches based on objective measurement of neural function are necessary. In this pilot study, we assessed the sensitivity of auditory chirp-evoked responses to the state of patients with severe brain injury as measured with CRS-R (Coma Recovery Scale - Revised). Methods A convenience sample of fifteen DOC patients was included in the study. Auditory stimuli, chirp-modulated at 1–120 Hz were used to evoke auditory steady-state response (ASSR). Phase-locking index (PLI) estimates within low gamma and high gamma windows were evaluated. Results The PLI estimates within a narrow low gamma 38–42 Hz window positively correlated with the CRS-R total score and with the scores of the Auditory and Visual Function subscales. In the same low gamma window, significant difference in the PLIs was found between minimally conscious (MCS) and vegetative state (VS) patients. We did not observe any between-group differences nor any significant correlations with CRS-R scores in the high gamma window (80–110 Hz). Conclusions Our results support the notion that the activity around 40 Hz may serve as a possible marker of the integrity of thalamocortical networks in prolonged DOC patients. Significance Auditory steady-state responses at gamma-band frequencies highlight the role of upper parts of auditory system in evaluation of the level of consciousness in DOC patients.
Collapse
Affiliation(s)
- Marek Binder
- Institute of Psychology, Jagiellonian University, ul. Ingardena 6, 30-060 Krakow, Poland.
| | - Urszula Górska
- Institute of Psychology, Jagiellonian University, ul. Ingardena 6, 30-060 Krakow, Poland
| | - Evaldas Pipinis
- Department of Neurobiology and Biophysics, Vilnius University, Sauletekio ave 7, LT-10257 Vilnius, Lithuania
| | - Aleksandras Voicikas
- Department of Neurobiology and Biophysics, Vilnius University, Sauletekio ave 7, LT-10257 Vilnius, Lithuania
| | - Inga Griskova-Bulanova
- Department of Neurobiology and Biophysics, Vilnius University, Sauletekio ave 7, LT-10257 Vilnius, Lithuania
| |
Collapse
|
16
|
Chen T, Lu S, Qian P, Chen G, Hu N. An automatic detection method for 40-Hz auditory steady state response and its application in prognosis of comatose patients. Clin Neurophysiol 2020; 131:703-715. [PMID: 31991313 DOI: 10.1016/j.clinph.2020.01.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2018] [Revised: 12/03/2019] [Accepted: 01/01/2020] [Indexed: 12/16/2022]
Abstract
OBJECTIVE We proposed a 40-Hz auditory steady-state response (ASSR) automatic detection method, and studied the prognosis of comatose patients by combining the 40-Hz ASSR detection results of multiple paradigms of auditory stimulation. METHODS The 40-Hz ASSR elicitation experiments were carried out on 32 comatose patients, with the detection results used as prognosis predictors. To achieve automatic detection, the detection was modeled as a binary hypothesis test for a sinusoidal waveform with unknown amplitude and phase, based on the generalized likelihood ratio test (GLRT). The patients were followed up for 6 months, and each patient's outcome was classified as either favorable outcome (severe disability, moderate disability or good recovery) or unfavorable outcome (vegetative state/unresponsive wakefulness syndrome or death) according to the Glasgow outcome scale (GOS). The performance of the prognosis predictors was assessed using the area under the receiver operating characteristic curve (AUC-ROC). RESULTS The largest AUC in univariate analysis involving a single stimulation paradigm was 0.849, while the AUC obtained by combining multiple predictors was increased to 0.966. CONCLUSIONS For comatose patients, the absence of 40-Hz ASSR in multiple stimulation paradigms may indicate an unfavorable prognosis. Furthermore, the combination of multiple auditory stimulation paradigms may increase the outcome prediction accuracy. SIGNIFICANCE The combination of multi-paradigm 40-Hz ASSR automatic detection results may provide a feasible automatic outcome prediction method for comatose patients.
Collapse
Affiliation(s)
- Tingting Chen
- School of Electronic and Information Engineering, Soochow University, Suzhou, Jiangsu 215006, China
| | - Shiqi Lu
- Emergency Department, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu 215006, China
| | - Ping Qian
- Emergency Department, The First People's Hospital of Taicang, Taicang Affiliated Hospital of Soochow University, Taicang, Jiangsu 215400, China
| | - Guolin Chen
- Emergency Department, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu 215006, China
| | - Nan Hu
- School of Electronic and Information Engineering, Soochow University, Suzhou, Jiangsu 215006, China.
| |
Collapse
|
17
|
Górska U, Binder M. Low- and medium-rate auditory steady-state responses in patients with prolonged disorders of consciousness correlate with Coma Recovery Scale - Revised score. Int J Psychophysiol 2019; 144:56-62. [PMID: 31381936 DOI: 10.1016/j.ijpsycho.2019.08.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2019] [Revised: 07/30/2019] [Accepted: 08/01/2019] [Indexed: 02/02/2023]
Abstract
Diagnosis of consciousness in patients with prolonged disorders of consciousness (PDOC) remains challenging since their responsiveness is often very impaired, while their assessment depends on observable behavior. The aim of this proof-of-concept study was to evaluate whether low- and medium-rate amplitude-modulated (AM) auditory steady-state responses (ASSRs) can be sensitive to the state of PDOC patients and may thus serve as a diagnostic tool which does not explicitly depend on a patient's cooperation. EEG was recorded from nine unresponsive wakefulness syndrome/vegetative state (UWS/VS) and eight minimally conscious state (MCS)/emergence from MCS patients during stimulation with two-minute trains of simple tones, amplitude modulated (AM) by 4 Hz, 6 Hz, 8 Hz, 12 Hz, 20 Hz, 40 Hz. The obtained ASSRs were then related to the Coma Recovery Scale - Revised (CRS-R) diagnosis and its total score. We observed significant correlations between mean inter-trial phase coherence (PC) (averaged across all stimulation frequencies) and total CRS-R score, as well as between 40 Hz relative power (RP) and total CRS-R score. Moreover, both parameters significantly differed between the patient groups. Our preliminary results suggest that a passive auditory stimulation protocol consisting of low- and medium-rate ASSRs might be used as an objective estimate of the level of neural dysfunction in PDOC patients. Consequently, the integrity of the auditory system appears to be an important predictor of the actual state of consciousness in PDOC patients.
Collapse
Affiliation(s)
- Urszula Górska
- Psychophysiology Laboratory, Institute of Psychology, Jagiellonian University, Krakow, Poland; Department of Neurophysiology, Donders Centre for Neuroscience, Radboud University Nijmegen, the Netherlands
| | - Marek Binder
- Psychophysiology Laboratory, Institute of Psychology, Jagiellonian University, Krakow, Poland.
| |
Collapse
|
18
|
Matsubara T, Ogata K, Hironaga N, Uehara T, Mitsudo T, Shigeto H, Maekawa T, Tobimatsu S. Monaural 40-Hz auditory steady-state magnetic responses can be useful for identifying epileptic focus in mesial temporal lobe epilepsy. Clin Neurophysiol 2018; 130:341-351. [PMID: 30669010 DOI: 10.1016/j.clinph.2018.11.026] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2018] [Revised: 10/19/2018] [Accepted: 11/28/2018] [Indexed: 02/03/2023]
Abstract
OBJECTIVE Patients with mesial temporal lobe epilepsy (mTLE) often exhibit central auditory processing (CAP) dysfunction. Monaural 40-Hz auditory steady-state magnetic responses (ASSRs) were recorded to explore the pathophysiology of mTLE. METHODS Eighteen left mTLE patients, 11 right mTLE patients and 16 healthy controls (HCs) were examined. Monaural clicks were presented at a rate of 40 Hz. Phase-locking factor (PLF) and power values were analyzed within bilateral Heschl's gyri. RESULTS Monaural 40-Hz ASSR demonstrated temporal frequency dynamics in both PLF and power data. Symmetrical hemispheric contralaterality was revealed in HCs. However, predominant contralaterality was absent in mTLE patients. Specifically, right mTLE patients exhibited a lack of contralaterality in response to left ear but not right ear stimulation, and vice versa in left mTLE patients. CONCLUSION This is the first study to use monaural 40-Hz ASSR with unilateral mTLE patients to clarify the relationship between CAP and epileptic focus. CAP dysfunction was characterized by a lack of contralaterality corresponding to epileptic focus. SIGNIFICANCE Monaural 40-Hz ASSR can provide useful information for localizing epileptic focus in mTLE patients.
Collapse
Affiliation(s)
- Teppei Matsubara
- Department of Clinical Neurophysiology, Neurological Institute, Faculty of Medicine, Graduate School of Medical Sciences, Kyushu University, Japan.
| | - Katsuya Ogata
- Department of Clinical Neurophysiology, Neurological Institute, Faculty of Medicine, Graduate School of Medical Sciences, Kyushu University, Japan
| | - Naruhito Hironaga
- Department of Clinical Neurophysiology, Neurological Institute, Faculty of Medicine, Graduate School of Medical Sciences, Kyushu University, Japan
| | - Taira Uehara
- Department of Clinical Neurophysiology, Neurological Institute, Faculty of Medicine, Graduate School of Medical Sciences, Kyushu University, Japan
| | - Takako Mitsudo
- Department of Clinical Neurophysiology, Neurological Institute, Faculty of Medicine, Graduate School of Medical Sciences, Kyushu University, Japan
| | - Hiroshi Shigeto
- Epilepsy and Sleep Center, Fukuoka Sanno Hospital, Fukuoka, Japan
| | | | - Shozo Tobimatsu
- Department of Clinical Neurophysiology, Neurological Institute, Faculty of Medicine, Graduate School of Medical Sciences, Kyushu University, Japan
| |
Collapse
|
19
|
Cortical Response to the Natural Speech Envelope Correlates with Neuroimaging Evidence of Cognition in Severe Brain Injury. Curr Biol 2018; 28:3833-3839.e3. [PMID: 30471997 DOI: 10.1016/j.cub.2018.10.057] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2018] [Revised: 08/27/2018] [Accepted: 10/28/2018] [Indexed: 11/21/2022]
Abstract
Recent studies identify severely brain-injured patients with limited or no behavioral responses who successfully perform functional magnetic resonance imaging (fMRI) or electroencephalogram (EEG) mental imagery tasks [1-5]. Such tasks are cognitively demanding [1]; accordingly, recent studies support that fMRI command following in brain-injured patients associates with preserved cerebral metabolism and preserved sleep-wake EEG [5, 6]. We investigated the use of an EEG response that tracks the natural speech envelope (NSE) of spoken language [7-22] in healthy controls and brain-injured patients (vegetative state to emergence from minimally conscious state). As audition is typically preserved after brain injury, auditory paradigms may be preferred in searching for covert cognitive function [23-25]. NSE measures are obtained by cross-correlating EEG with the NSE. We compared NSE latencies and amplitudes with and without consideration of fMRI assessments. NSE latencies showed significant and progressive delay across diagnostic categories. Patients who could carry out fMRI-based mental imagery tasks showed no statistically significant difference in NSE latencies relative to healthy controls; this subgroup included patients without behavioral command following. The NSE may stratify patients with severe brain injuries and identify those patients demonstrating "cognitive motor dissociation" (CMD) [26] who show only covert evidence of command following utilizing neuroimaging or electrophysiological methods that demand high levels of cognitive function. Thus, the NSE is a passive measure that may provide a useful screening tool to improve detection of covert cognition with fMRI or other methods and improve stratification of patients with disorders of consciousness in research studies.
Collapse
|
20
|
Low and medium frequency auditory steady-state responses decrease during NREM sleep. Int J Psychophysiol 2018; 135:44-54. [PMID: 30452935 DOI: 10.1016/j.ijpsycho.2018.11.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2018] [Revised: 11/14/2018] [Accepted: 11/15/2018] [Indexed: 11/23/2022]
Abstract
Previous research on auditory steady-state responses (ASSRs) demonstrated sensitivity of 40 Hz ASSR to changes in the level of arousal, both in sleep and in general anaesthesia. In this study we extended the range of stimulation frequencies, using also low and medium stimulation frequencies (4, 6, 8, 12, 20, 40 Hz) and studied their susceptibility to the loss of consciousness in NREM sleep (N2 and N3 stages). Effects of NREM sleep were examined in power domain with relative power (RP), and in phase domain using inter-trial phase coherence (PC) parameter. The activity in power domain was also compared to no-stimulation data. Regions displaying significant waking-NREM sleep differences were selected using non-parametric suprathreshold cluster test. For 4, 6, 20 and 40 Hz stimulation relative power of ASSRs was lower in NREM sleep, with maximal change for 40 Hz stimulation. This decrease was not seen in no-stimulation condition. For all stimulation frequencies (except 12 Hz) we observed decrease of phase coherence of ASSR during NREM sleep. Our results demonstrate that low and medium frequency ASSRs are state-sensitive, thus susceptible to loss of consciousness during NREM sleep. Diminishing of power and phase coherence may result from cortical down states and/or thalamic inhibition. Our results support possible use of low- and medium-frequency ASSRs for discrimination between states of altered consciousness and emphasize the role of the auditory system in determining these variations.
Collapse
|
21
|
Khanmohammadi S, Laurido-Soto O, Eisenman LN, Kummer TT, Ching S. Intrinsic network reactivity differentiates levels of consciousness in comatose patients. Clin Neurophysiol 2018; 129:2296-2305. [PMID: 30240976 PMCID: PMC6202231 DOI: 10.1016/j.clinph.2018.08.004] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2018] [Revised: 08/13/2018] [Accepted: 08/23/2018] [Indexed: 12/14/2022]
Abstract
OBJECTIVE We devise a data-driven framework to assess the level of consciousness in etiologically heterogeneous comatose patients using intrinsic dynamical changes of resting-state Electroencephalogram (EEG) signals. METHODS EEG signals were collected from 54 comatose patients (GCS ⩽ 8) and 20 control patients (GCS > 8). We analyzed the EEG signals using a new technique, termed Intrinsic Network Reactivity Index (INRI), that aims to assess the overall lability of brain dynamics without the use of extrinsic stimulation. The proposed technique uses three sigma EEG events as a trigger for ensuing changes to the directional derivative of signals across the EEG montage. RESULTS The INRI had a positive relationship with GCS and was significantly different between various levels of consciousness. In comparison, classical band-limited power analysis did not show any specific patterns correlated to GCS. CONCLUSIONS These findings suggest that reaching low variance EEG activation patterns becomes progressively harder as the level of consciousness of patients deteriorate, and provide a quantitative index based on passive measurements that characterize this change. SIGNIFICANCE Our results emphasize the role of intrinsic brain dynamics in assessing the level of consciousness in coma patients and the possibility of employing simple electrophysiological measures to recognize the severity of disorders of consciousness (DOC).
Collapse
Affiliation(s)
- Sina Khanmohammadi
- Department of Electrical & Systems Engineering, Washington University in St. Louis, St. Louis, MO 63130, USA; Department of Neurology, Washington University School of Medicine, St. Louis, MO 63110, USA.
| | - Osvaldo Laurido-Soto
- Department of Neurology, Washington University School of Medicine, St. Louis, MO 63110, USA.
| | - Lawrence N Eisenman
- Department of Neurology, Washington University School of Medicine, St. Louis, MO 63110, USA.
| | - Terrance T Kummer
- Department of Neurology, Washington University School of Medicine, St. Louis, MO 63110, USA.
| | - ShiNung Ching
- Department of Electrical & Systems Engineering, Washington University in St. Louis, St. Louis, MO 63130, USA; Department of Biomedical Engineering, Washington University in St. Louis, St. Louis, MO 63130, USA; Division of Biology and Biomedical Science, Washington University in St. Louis, St. Louis, MO 63130, USA.
| |
Collapse
|