Changes in effective connectivity between motor and sensory regions in finger movement task

Abstract

A challenging question lies in how brain distant regions are integrated into an orderly unity in a movement task. Integration of Electroencephalography (EEG) and functional Magnetic Resonance Imaging (fMRI) data yields the possibility of studying the temporal dynamics of brain network involved in visumotor task. The aim of this paper is to investigate the brain dynamic sensory-motor network associated with finger movement. To this end we modeled brain activity by combining fMRI and EEG using fMRI-driven EEG analysis approach. The EEG and fMRI data was obtained from two healthy subjects during a key pressing task. Dynamic Causal Modeling (DCM) was employed to extract connectivity changes between sources. According to fMRI analysis, significant activation was detected in primary motor cortex, somatosensory, cerebellum, precuneus and visual areas. Comparisons of 18 models showed that precuneus and cerebellum receive the visual information directly from visual cortex. Dynamic changes of effective connectivity demonstrated 6 times increase in exertion of cerebellum on the primary motor cortex in left hand movement in relative to non-movement period. According to the best model interactions between somatosensory area and precuneus decreased during finger movement period. Connectivity strength between visual and precuneus had no changes.