Evidence for a sustained cerebrovascular response following motor practice.

Motor tasks have been extensively used to probe neuroplasticity and the changes in MRI signals are often associated with changes in performance. Changes in performance have been linked to alterations in resting-state fluctuations of BOLD signal after the end of the task. We hypothesize that motor learning will induce localized changes in cerebral blood flow (CBF) sustained even after the execution of a motor learning task. We implemented a new motor task to probe neuroplasticity and mapped the associated cerebrovascular responses. Twenty healthy volunteers underwent two MRI sessions 1-week apart: a task session with a sequence learning task performed with a data glove and a control session. During each session, CBF and BOLD signals were acquired during the task and during two periods of rest, each lasting 8 min, before and after execution of the task. Evoked BOLD and CBF responses to the motor task were seen to decrease in a regionally specific manner as the task proceeded and performance accuracy improved. We observed a localized increase in resting CBF in the right extra-striate visual area that was sustained during the 8-min rest period after the completion of the motor learning task. CBF increase in the area was accompanied by a regional increase in local BOLD signal synchronization. Our observation suggests an important connection between neuroplastic changes induced by learning and sustained perfusion in the apparently resting brain followed task completion.