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Published on: March 8, 2019
Ripples of consciousness
Jacobo D Sitt1, Jean-Rémi King, Lionel Naccache
1Cognitive Neuroimaging Unit, Institut National de la Santé et de la Recherche Médicale, U992, F-91191 Gif/Yvette, France; NeuroSpin Center, Institute of BioImaging Commissariat à l'Energie Atomique, F-91191 Gif/Yvette, France; Institut du Cerveau et de la Moelle Épinière Research Center, Institut National de la Santé et de la Recherche Médicale, U975 Paris, France.
Trends in Cognitive Sciences
|October 8, 2013
Summary
The complexity of brain responses to transcranial magnetic stimulation can differentiate conscious from unconscious individuals. This finding offers a new way to quantitatively measure consciousness states.
Area of Science:
- Neuroscience
- Cognitive Science
- Electrophysiology
Background:
- Assessing consciousness is challenging, especially in non-communicative individuals.
- Current methods for evaluating consciousness lack objective quantitative measures.
Purpose of the Study:
- To investigate if the complexity of electrophysiological brain responses can distinguish between conscious and unconscious states.
- To introduce a novel, quantitative method for assessing consciousness.
Main Methods:
- Electrophysiological recordings were used to measure brain responses.
- Transcranial magnetic stimulation (TMS) was applied to elicit brain responses.
- Complexity analysis was performed on the recorded brain activity patterns.
Main Results:
- The complexity of the brain's response to TMS reliably distinguished conscious from unconscious humans.
- This complexity measure was effective across various conditions affecting consciousness.
Conclusions:
- The complexity of TMS-evoked brain activity is a valid marker for consciousness.
- This novel approach enables a quantitative assessment of consciousness states, with significant theoretical and clinical implications.
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