Here we examined changes in muscle coordination associated with improved motor performance after partnered, dance-based rehabilitation in individuals with mild-moderate idiopathic Parkinson's disease. Using motor module (a.k.a muscle synergy) analysis we identified changes in the modular control of overground walking and standing reactive balance that accompanied clinically meaningful improvements on behavioral measures of balance, gait, and disease symptoms after three-weeks of daily Adapted Tango classes. In contrast to previous studies that revealed a positive association between motor module number and motor performance, none of the six participants in this pilot study increased motor module number despite improvements in behavioral measures of balance and gait performance. Instead, motor modules were more consistently recruited and distinctly organized immediately after rehabilitation, suggesting more reliable motor output. Further, the pool of motor modules shared between walking and reactive balance increased after rehabilitation, suggesting greater generalizability of motor module function across tasks. Our work is the first to show that motor module distinctness, consistency, and generalizability are more sensitive to improvements in gait and balance function following short-term rehabilitation than motor module number. Moreover, as similar differences in motor module distinctness, consistency, and generalizability have been demonstrated previously between in healthy young adults with and without long-term motor training, our work suggest commonalities in the structure of muscle coordination associated with differences in motor performance across the spectrum from motor impairment to expertise.
- muscle coordination
- muscle synergy
- Copyright © 2016, Journal of Neurophysiology