NEURO - Prognostication Using Late Somatosensory Evoked - Potentials

NEURO - Prognostication Using Late Somatosensory Evoked - Potentials

The main aim of this study is to develop a new technique for the passive diagnosis of cognitive-motor dissociation, with the detection of motor intention in a comatose patient by analysing the EEG signal and in particular the ERD/ERS amplitudes in the motor cortex after stimulation of the median nerve.

The utilisation of brain-computer interfaces (BCI) employing median nerve stimulation has the potential to yield novel insights into the enhancement of neuroprognostication. The application of painless, low-intensity electrical stimulation to the median nerve has been shown to activate the somatosensory cortex and the motor cortex via cutaneous and proprioceptive afferents. The activation in question has been shown to induce specific modulations of the electroencephalogram (EEG) signal, characterised by event-related desynchronisation (ERD) during stimulation, followed by resynchronisation (ERS) afterwards. The application of this stimulation during a motor task - that is to say, voluntary movement or motor imagery - results in a marked attenuation of post-stimulation ERS, or even its complete absence. The intention to move a hand, when coinciding with median nerve stimulation, amplifies the cortical ERD/ERS signatures, and is made more easily detectable by machine learning algorithms.

The main aim of this study is to develop a new technique for the passive diagnosis of cognitive-motor dissociation, with the detection of motor intention in a comatose patient by analysing the EEG signal and in particular the ERD/ERS amplitudes in the motor cortex after stimulation of the median nerve.

Inclusion Criteria:

• Patients must be aged 18 years or over;
• Patients must be admitted to the intensive care unit with a cerebrovascular pathology;
• Patients must be in a comatose state with a Glasgow score strictly less than 8, 24 hours after stopping sedation.
• Representative of the patient informed of the research and not objecting to it, information and collection of the participant's non-objection if recovery of the ability to understand the content of the information note,
• The patient is a recipient of or affiliated with a social security scheme.

Exclusion Criteria:

• Bilateral lesions of the motor cortex or cortico-spinal fasciculus,
• Cutaneous infection of the scalp or any other lesion making surface electroencephalography impossible,
• Patient whose short-term survival (48 - 72 hours) seems compromised,
• Severe peripheral neuromyopathy,
• Severe Acute Respiratory Distress Syndrome at the time of screening,
• Hearing-impaired patients with hearing aids,
• Pregnant or breastfeeding woman,
• Patient under legal protection (persons deprived of their liberty or under guardianship).