Cortical activation of unilateral upper limb tasks: Perspectives for stroke rehabilitation

• Muller Camille
• Bakhti Karima
• Muthalib Makii
• Mottet Denis
• Delorme Marion
• Froger Jérôme
• Perrey S.
• Laffont Isabelle

• EEG
• FNIRS
• Kinematics
• Neuroplasticity
• Motor function

Background and Aim: 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 mapping of the movement-related cortical activity to unveil underlying mechanisms of upper limb (UL) recovery. This fNIRS-fEEG study aims to depict reference activation patterns of motor cortex related to motor performance during UL functional tasks. Methods: Young healthy participants realized two unilateral UL tasks: i) a reaching target task and ii) a circular tracing task with speed and accuracy. A combined fNIRS-fEEG system was used to record motor cortex activations during each task. Results: With 20 healthy young subjects we replicated the classical kinematics results of the healthy UL movement. Neuro-imagery results provided by the fNIRS showed a co-activation of both motor cortex with a greater contralateral activity. With the EEG we highlighted power modification in the alpha-beta rhythm with a desynchronization occurring at movement. Conclusion: In parallel to the description of the reference brain pattern of UL movement, we showed that combined fNIRS-fEEG can be used in a rehabilitation unit to provide a “Holter of the brain plasticity” during functional movement. Further analysis with the older healthy subjects will give us information about ageing effects. Perspectives of this project will be the exploration of these brain-movement patterns in post-stroke patients in rehabilitation.