Injury patterns associated with cognitive motor dissociation.

Area of Science:

• Neuroscience
• Neurology
• Medical Imaging

Background:

• Cognitive motor dissociation (CMD) in unresponsive acute brain injury patients predicts functional recovery.
• CMD detection via EEG and machine learning has clinical implications but underlying mechanisms are unknown.
• Understanding CMD mechanisms is crucial for patient care and therapeutic guidance.

Purpose of the Study:

• To test the hypothesis that CMD results from a failure to integrate comprehended motor commands with motor outputs.
• To analyze structural lesion patterns and network dysfunction in patients with and without CMD.
• To identify potential neuroimaging markers for CMD screening.

Main Methods:

• Manual segmentation of MRI sequences (T2-FLAIR, DWI) to quantify structural injury in 107 patients.
• Lesion pattern analysis to identify commonalities in CMD (n=21) and non-CMD (n=86) groups.
• Assessment of thalamocortical and cortico-cortical network connectivity using EEG (ABCD classification, WPPC).

Main Results:

• Distinct lesion patterns were identified for CMD and non-CMD groups; midbrain lesions were absent in CMD patients.
• CMD patients with subcortical lesions showed preserved thalamocortical network function but altered long-range cortico-cortical connectivity.
• Patients with bilateral cortical lesions and CMD showed preserved cortico-cortical network function.

Conclusions:

• Failure of motor command integration at the anterior forebrain mesocircuit level underlies CMD in patients with subcortical lesions.
• Preserved cortico-cortical network function is associated with CMD detection in patients with bilateral cortical lesions.
• Structural MRI and resting EEG may enable CMD screening.