Dynamic Causal Modelling identifies abnormal effective connectivity between supratentorial cortex and cerebellum in Multiple Sclerosis.

Motivation: Multi-modal approaches are crucial for understanding how pathological conditions affect brain network connectivity and alter the BOLD signal. Goal(s): Characterise the causal architecture of brain regions activated during a visuomotor task and see how the applied grip force modulates brain connectivity in Multiple Sclerosis (MS). Approach: Dynamic Causal Modelling (DCM) was used to estimate the effective connectivity of a six-regions brain network in 9 healthy and 15 MS participants. Results: Both, MS and healthy volunteers presented the same effective connectivity architecture, however grip-force modulation of BOLD signal and cortical-cerebellar recruitment was altered in MS. Impact: Investigating how MS affects the cortical and cerebellar involvement during a visuomotor task provides better understanding of excitatory/inhibitory mechanisms and unravel the disease impact on brain networks. DCM can lead to more mechanistic insights into MS progression and therapeutic targets.