Figure 5.

Effects of femoral nerve stimulation on soleus voluntary activity in two stroke participants and a control participant. Traces of averaged rectified soleus EMG activities of ten trials are presented on the paretic sides of stroke participants with moderately (A) and slightly (B) impaired coordination and on the right leg of a control participant (C). For each participant, traces are plotted against the latency presented from 20 ms to 80 ms after femoral nerve stimulation (lower scale), and from 0 to 48 ms after the zero central delay (upper scale). Arrows indicate the zero central delay, which is the expected time of arrival of the fastest femoral nerve Ia volley at the motoneurone level of soleus. Horizontal lines represent the mean amplitude of the unconditioned EMG activity before femoral nerve stimulation (baseline EMG level). The early facilitation was assessed within the time window from 0 to 6 ms after zero central delay. Asterisks represent significant modulations of soleus voluntary EMG within the four time windows of analysis from 0 to 6 ms, 12 to 24 ms, 24 to 36 ms and 36 to 48 ms after the zero central delay (* p ≤ 0.05; ** p ≤ 0.01; *** p ≤ 0.001).