An Investigation of Changes in Hemispheric Functional Connectivity after Stroke Based on fNIRS.

Stroke is a severe cerebrovascular disease. The understanding of the process of post-stroke brain recovery is crucial for prescribing rehabilitation plan. The resting-state functional connectivity (rsFC) has been used to analyze the brain functional networks with the aim to understand the post-stroke neuroplasticity. In this investigation, the rsFC data has been collected from 7 stroke patients and 7 healthy control subjects using functional Near-Infrared Spectroscopy (fNIRS) to explore the possible changes in hemispheric functional connectivity (FC) in stroke patients in comparison with the healthy subjects. The fNIRS signals were captured while the participants were asked to do the upper and lower limb motor imagery. A reduced FC was found between the damaged hemisphere and other regions in stroke patients. For patients with right hemiplegia, the FC strength between the right primary motor cortex (RPMC) and the Prefrontal Cortex (PFC) regions decreased by 0.18 (p<0.05). The change in functional connectivity indicates the existence of the post-stroke brain's plasticity as a compensatory mechanism. Hence the FC study could be used to guide and improve the effectiveness of the stroke rehabilitation.