K. Jaureguirenaud et al., SKEW DEVIATION OF THE EYES IN NORMAL HUMAN-SUBJECTS INDUCED BY SEMICIRCULAR CANAL STIMULATION, Neuroscience letters, 205(2), 1996, pp. 135-137
Computerised video-oculography and scleral search coils were used to r
ecord the horizontal, vertical and torsional binocular eye movements o
f human subjects exposed to roll oscillation at 0.4 Hz about earth-hor
izontal and earth-vertical naso-occipital axes in darkness. The stimul
i provoked a dominant torsional ('ocular counter-rolling') response wi
th a ratio of peak slow phase eye velocity to stimulus velocity which
was not significantly different for earth-horizontal (0.39, SD 0.08) o
r earth-vertical axis orientations (0.40, SD 0.08). For all conditions
the responses also had a head-vertical component which was disconjuga
te ('skew deviation'). The cumulative, vertical, slow phase divergence
was 5.8 degrees, SD 1.3 degrees, about upright and 4.3 degrees, SD 0.
6 degrees, when supine. This is the first demonstration that dynamic r
oll stimuli provoke a skew deviation in normal human subjects. At the
frequency tested, the skew was driven by vertical semicircular canal s
timulation.