Early detection of consciousness in critically ill patients with severe brain injuries can profoundly impact prognostication and clinical care decisions. Advanced multimodal protocols to detect signs of consciousness include standardized behavioral assessments, task-based functional magnetic resonance imaging (fMRI), and task-based electroencephalography (EEG). However, these approaches have limited diagnostic sensitivity because patients may lack auditory function, attention, language, or other cognitive capacities required to perform a task or process a sensory stimulus, even if they are conscious. Transcranial magnetic stimulation EEG (TMS-EEG) has the potential to overcome these limitations by directly engaging corticothalamic circuits to compute the perturbational complexity index (PCI), an emerging indicator of consciousness. To date, TMS-EEG studies have focused on patients in the subacute or chronic stage of recovery from severe brain injury. Here, we report the proof-of-concept application of TMS-EEG for a critically ill patient in the acute stage of brain injury, in which multimodal assessments suggested a vegetative state/unresponsive wakefulness syndrome. We demonstrate that TMS-EEG may detect signs of consciousness that elude current advanced evaluations, showing the feasibility of TMS-EEG as part of a multimodal protocol for assessing consciousness in the intensive care unit.
Abstract
Case Reports
Journal Article
eng
42090748
Fecchio, Matteo, et al. "Covert Brain Complexity in the Intensive Care Unit." Cortex; a Journal Devoted to the Study of the Nervous System and Behavior, vol. 201, 2026, pp. 1-9.
Fecchio M, Schreier DR, Cambareri MK, et al. Covert brain complexity in the intensive care unit. Cortex. 2026;201:1-9.
Fecchio, M., Schreier, D. R., Cambareri, M. K., Nisticò, V., Freeman, H. J., Lawrence, P. K., Bodien, Y. G., Young, M. J., Wu, O., & Edlow, B. L. (2026). Covert brain complexity in the intensive care unit. Cortex; a Journal Devoted to the Study of the Nervous System and Behavior, 201, 1-9. https://doi.org/10.1016/j.cortex.2026.03.021
Fecchio M, et al. Covert Brain Complexity in the Intensive Care Unit. Cortex. 2026 Apr 17;201:1-9. PubMed PMID: 42090748.
* Article titles in AMA citation format should be in sentence-case
TY - JOUR
T1 - Covert brain complexity in the intensive care unit.
AU - Fecchio,Matteo,
AU - Schreier,David R,
AU - Cambareri,Morgan K,
AU - Nisticò,Veronica,
AU - Freeman,Holly J,
AU - Lawrence,Phoebe K,
AU - Bodien,Yelena G,
AU - Young,Michael J,
AU - Wu,Ona,
AU - Edlow,Brian L,
Y1 - 2026/04/17/
PY - 2025/09/23/received
PY - 2026/02/15/revised
PY - 2026/03/28/accepted
PY - 2026/5/7/medline
PY - 2026/5/7/pubmed
PY - 2026/5/6/entrez
KW - Coma
KW - Consciousness
KW - Electroencephalography
KW - Intensive Care Unit
KW - Transcranial Magnetic Stimulation
SP - 1
EP - 9
JF - Cortex; a journal devoted to the study of the nervous system and behavior
JO - Cortex
VL - 201
N2 - Early detection of consciousness in critically ill patients with severe brain injuries can profoundly impact prognostication and clinical care decisions. Advanced multimodal protocols to detect signs of consciousness include standardized behavioral assessments, task-based functional magnetic resonance imaging (fMRI), and task-based electroencephalography (EEG). However, these approaches have limited diagnostic sensitivity because patients may lack auditory function, attention, language, or other cognitive capacities required to perform a task or process a sensory stimulus, even if they are conscious. Transcranial magnetic stimulation EEG (TMS-EEG) has the potential to overcome these limitations by directly engaging corticothalamic circuits to compute the perturbational complexity index (PCI), an emerging indicator of consciousness. To date, TMS-EEG studies have focused on patients in the subacute or chronic stage of recovery from severe brain injury. Here, we report the proof-of-concept application of TMS-EEG for a critically ill patient in the acute stage of brain injury, in which multimodal assessments suggested a vegetative state/unresponsive wakefulness syndrome. We demonstrate that TMS-EEG may detect signs of consciousness that elude current advanced evaluations, showing the feasibility of TMS-EEG as part of a multimodal protocol for assessing consciousness in the intensive care unit.
SN - 1973-8102
UR - https://www.unboundmedicine.com/prime/citation/42090748/Covert_brain_complexity_in_the_intensive_care_unit.
DB - PRIME
DP - Unbound Medicine
ER -


