Effect of Vibration on Arm Movements.

A) Stability error (mean ± SD) reported at proximal and distal targets for stroke (n = 10) and control (n = 5) subjects. Stability error increased for both subject groups while stabilizing in Fd. Tendon vibration decreased stability error. B) The frequency of hand oscillation (Hz, mean ± SD) at the target was not significantly affected by the Fd or tendon vibration. However, control subjects exhibited significantly higher error frequencies than the stroke group. C) Changes in grip pressure (psig, mean ± SD) across blocks of trials as subjects made movements at proximal and distal target locations. Control subjects increased their grip pressure while attempting to stabilize their hand during movements made in Fd. Stroke subjects did not demonstrate significant increases in grip pressure while stabilizing in Fd.