Cortical activation patterns of unilateral upper limb tasks in healthy adults: perspectives for stroke rehabilitation
Résumé
Background and aims Post-stroke brain activations and their evolution through rehabilitation is a subject of major interest. Two non-invasive neuroimaging methods allow for recording the task-related brain activation for bedside use or in field monitoring: functional near-infrared spectroscopy (fNIRS) and electroencephalography (fEEG) respectively based on haemodynamic response and electrical activity of brain regions. Coupling both methods could lead to a better spatiotemporal cortical activity analysis related to upper limb (UL) tasks to unveil underlying UL recovery mechanisms. This fNIRS-fEEG study aims to depict reference activation patterns of motor cortex related to motor performance during UL functional tasks.
Methods 21 young and 21 old healthy participants realized two unilateral UL tasks: i) a reaching target task and ii) a circular steering task with speed and accuracy. A combined fNIRS-fEEG system was used to record motor cortices activations during each task.
Results A preserved lateralization of the brain activation was found in the older group with a higher amplitude in contralateral on the reaching task and a bi-activation on the circular steering task. Modification of EEG power spectra showed a lower desynchronisation and synchronisation of the alpha-beta rhythms on the two functional tasks in the older group,
Conclusions In parallel to the description of the reference brain patterns of UL movement and its reorganization with healthy ageing, we showed that combined fNIRS-fEEG could be used in a rehabilitation unit to follow neuroplasticity evolvement during functional tasks. Perspectives of this project will be the exploration of the movement-related brain patterns in post-stroke patients and its potential link with functional recovery.