Fig. 3.

Swing time variability increased over time, off therapy, and the degree of increase was related to initial levels of NBM atrophy. (A) Example of a kinetic trace during the stepping-in-place (SIP) task at Initial Programming (IP) and (B) three years later in the same individual. (C) Comparison of swing time variability during the SIP task at IP (blue) and 3 years (pink). Swing time variability significantly increased (i.e., worsened) over time. (D) Voxels showing a negative correlation between gray matter volume and percent change in swing time variability on the SIP task from IP to 3 years later. Individuals with lower gray matter volume showed a trend of greater increases in swing time variability over time. The colour bar represents p-values (uncorrected). MNI coordinates of each slice are shown at the bottom. Error bars represent SEM. * indicates significant differences. (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.)