VCR and VOR responses to increasing current amplitudes.

<p><i>A</i>, Pathways connecting the vestibular nerve to neck or extraocular motoneurons. <i>B</i>-<i>D</i>, Average head (blue) and eye (red) movement traces, in monkey J and B, evoked using current amplitudes of 50 (B), 75 (C), and 100% (D) of the maximum for pulse trains delivered at 300pps lasting 100ms. Gray bars indicate stimulus duration and shading represents standard error. Note that for some velocity traces the standard error is smaller than the line thickness. Movements away from implanted side are upwards. Arrows show rebound effect due to the release of inhibition. Insets show peak head and eye velocities for the corresponding traces. <i>EOM</i>, extraocular motoneuron; <i>INC</i>, interstitial nucleus of Cajal; <i>MRST</i>, medial reticulospinal tract; <i>MN</i>, motoneuron; <i>VST</i>, vestibulospinal tract; <i>VN</i>, vestibular nuclei.</p

VCR and VOR response latency and relative contribution to gaze.

<p><i>A</i>-<i>B</i>, Latency of evoked eye or head movements using a 2 standard deviation (A) or slope intercept measurement (B). <i>C</i>, Plots of eye versus head movement amplitude during pulse trains delivered at 50, 100, 200 and 300pps. <i>D</i>, Top panels show the contribution of head and eye to instantaneous gaze velocity during pulse trains delivered at the maximum current amplitude and 300pps. Bottom traces show the contribution of head and eye to cumulative gaze position. The average gaze velocity (top panels) and position (bottoms panels) traces are also plotted for comparison.</p

Interaction of vestibular-driven head and eye movements.

<p><i>A</i>, Average gaze, eye and head position (top panels) and velocity (bottom panels) traces during stimulations when the head was restrained and free. Gray bars indicate stimulus duration and shading represents standard error. <i>B</i>, Plots of average gaze movement amplitude during pulse trains delivered at 50, 100, 200 and 300pps when head-restrained versus free. <i>D</i>, Plots of average eye movement amplitude during pulse trains delivered at 50, 100, 200 and 300pps when head-restrained versus free.</p

Average VCR and VOR responses to increasing pulse rates.

<p><i>A</i>-<i>D</i>, Average head (blue) and eye (red) movement traces, in monkey J and B, evoked using increasing pulse rates of 50 (A), 100 (B), 200 (C) and 300pps (D) at maximum current amplitude. <i>E</i>-<i>G</i>, Plots of peak head and eye velocities as a function of pulse rate for current amplitudes of 50 (E), 75 (F), 100% (G) of the maximum.</p