Fig. 2.

Eye velocity responses to pulse-frequency-modulated, constant current, symmetric biphasic pulses delivered at a modulation frequency of 2 Hz with stimulus intensity = 100% to the left horizontal semicircular (SCC) of CH205 (A), the left anterior SCC of CH207 (B), and the left posterior SCC of CH207 (C). Thick red/solid line indicates the component of eye movement about the horizontal axis, green/dotted line indicates the left anterior-right posterior (LARP) axis, and blue/dashed line indicates the right-anterior/left-posterior (RALP) axis. Thin black/dashed trace shows the angular head velocity about the RALP axis equivalent to the stimulus presented. Thin black/solid trace represents the delivered pulse rate of the stimulus (right-hand ordinate). Vertical gray lines represent the time of peak eye velocity for a given cycle. Mean responses for each dataset are in the left column (SD<19 dps for all datasets). The animal was kept stationary to examine responses to electrical stimulation alone. The largest amplitude trace in each figure represents the eye movement component about the desired axis of rotation while other traces represent undesired eye movement components. Refer to Fig. 3D for orientation of eye movement axes.