Fig. 2.

Time-frequency analysis (upper) and averaged evoked potential (lower) for contact 105, with all contralateral movement conditions collapsed together. Zero corresponds to visual stimulus onset. Note the visual evoked potential synchronized to the visual stimulus between 0 and 0.5 seconds and associated low frequency increase in power. A later increase in high-frequency power and drop in low-frequency power associated with actual movement occurred between 0.5 seconds and 1.5 seconds. Finally, there was a persistent low-frequency increase in power associated with the steady-state movement response after 1.5 seconds.