Auditory cueing modulates motor performance and brain activity in early Parkinson's disease-a kinematic and fMRI study.

Cues are specific references that support motor performance by improving speed, timing, and amplitude while reducing variability. This study aimed at investigating the effects of external auditory cueing on bradykinesia-related kinematic deficits and their neural correlates during a hand-tapping task in people with Parkinson's disease (pwPD) and healthy controls (HC). Twenty-six pwPD and 20 HC performed a right hand-tapping fMRI task either in a self-paced condition (NOCue) or following an auditory cue (Cue). Hand-tapping kinematics were objectively quantified using an optical-fiber glove. PwPD showed reduced hand-tapping amplitude and a greater sequence effect on amplitude than HC during NOCue condition. Cueing attenuated the sequence effect on amplitude in pwPD. During the NOCue condition, pwPD showed reduced activity of pallidum/thalamus relative to HC. No group differences emerged during Cue condition. During Cue relative to NOCue condition, pwPD showed higher activity of pallidum, parietal, temporal, sensorimotor, insular, and cerebellar regions, alongside reduced activation in of paracentral gyrus and cerebellum. Higher activity of pallidum correlated with better motor performance and higher positive effects of cueing. Our results demonstrated that auditory cueing reduces bradykinesia in pwPD possibly by facilitating basal ganglia activity and reducing the need of movement programming.