Cerebral hemodynamic changes during motor imagery and passive robot-assisted movement of the lower limbs

Background: Neurovascular Coupling is the cerebral mechanism responsible for linking neuronal activity, cerebral metabolism and regional cerebral blood flow (CBF). The direct relation between functional brain activity during active, passive and motor imagery paradigms and changes in CBF has been widely investigated using different techniques. However, CBF changes have not been investigated beat by beat during robot assisted passive movement (PM) and motor imagery (MI) of lower limb, yet. Materials and methods: We investigated beat-to-beat hemodynamic changes in 8 healthy subjects using TCD during MI and robot-assisted PM of lower limb. Results: The results showed that MI and PM induce a significant CBFv increase and that PM and MI lead to similar hemodynamic changes in healthy subjects. Conclusions: The findings may be useful to better understand the variation of CBFv in brain pathology and to develop more specific and efficient rehabilitation therapy protocols in neurological diseases, such as stroke.