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.