Music Improvisation Increases Motor and Reward Responses: an fMRI study with survivors of stroke and control participants

Optimizing music interventions for stroke rehabilitation requires understanding their underlying mechanisms. This study evaluates motor, autonomic, affective, and neural, responses during a drum playing task with varied music playing (improvisation vs maintaining the beat) and music accompaniment (live vs recorded) conditions, completed by sixteen survivors of stroke and sixteen neurologically normal control (NC) participants. Motor responses were characterized by total acceleration of hand movements (accelerometry) and wrist flexor activation (electromyography; EMG). Autonomic response was evaluated with tonic response of electrodermal activity (EDA). Affective responses were evaluated with 5-point Likert ratings of pleasure, physical effort, and cognitive challenge. Neural response was evaluated in a subset of eleven stroke and eleven NC participants with fMRI, using region of interest analysis in the supplementary motor area (SMA), upper limb region of the primary motor cortex (M1ul) and ventral striatum (VS). Findings demonstrate that improvisation increased total acceleration, EMG, tonic EDA, and brain activity in the SMA, M1ul and VS. Improvisation and live accompaniment increased pleasure ratings. A composite score of reward-related responses was positively associated with both total acceleration and EMG. Survivors of stroke had higher ratings of physical effort and cognitive challenge compared to NC participants. These findings support the benefit of music improvisation for improving motor response and reward among survivors of stroke. The positive association between reward and motor responses suggests an important role of reward for improving motor performance, which may be beneficial for enhancing stroke rehabilitation outcomes