Skew deviation of the eyes in normal human subjects induced by semicircular canal stimulation

Computerised video-oculography and scleral search coils were used to record the horizontal, vertical and torsional binocular eye movements of human subjects exposed to roll oscillation at 0.4 Hz about earth-horizontal and earth-vertical naso-occipital axes in darkness. The stimuli provoked a dominant torsional ('ocular counter-rolling') response with a ratio of peak slow phase eye velocity to stimulus velocity which was not significantly different for earth-horizontal (0.39, SD 0.08) or earth-vertical axis orientations (0.40, SD 0.08). For all conditions the responses also had a head-vertical component which was disconjugate ('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 roll stimuli provoke a skew deviation in normal human subjects. At the frequency tested, the skew was driven by vertical semicircular canal stimulation.

[1]  I. Curthoys,et al.  Jerk-waveform see-saw nystagmus due to unilateral meso-diencephalic lesion. , 1994, Brain : a journal of neurology.

[2]  W. Engel,et al.  IMMUNOPEROXIDASE LOCALIZATION OF ALPHA BUNGAROTOXIN: A NEW APPROACH TO MYASTHENIA GRAVIS * , 1976, Annals of the New York Academy of Sciences.

[3]  M. B. Bender,et al.  COMPENSATORY EYE MOVEMENTS INDUCED BY VERTICAL SEMICIRCULAR CANAL STIMULATION. , 1964, Experimental neurology.

[4]  J I Simpson,et al.  EYE‐MUSCLE GEOMETRY AND COMPENSATORY EYE MOVEMENTS IN LATERAL‐EYED AND FRONTAL‐EYED ANIMALS * , 1981, Annals of the New York Academy of Sciences.

[5]  T. Brandt,et al.  Skew deviation with ocular torsion: A vestibular brainstem sign of topographic diagnostic value , 1993, Annals of neurology.

[6]  E Fluur,et al.  Utricular stimulation and oculomotor reactions , 1970, The Laryngoscope.

[7]  M. Gresty,et al.  Ocular tilt reaction with peripheral vestibular lesion , 1979, Annals of neurology.

[8]  L R Young,et al.  Three‐Dimensional Eye Velocity Measurement following Postrotational Tilt in the Monkey a , 1992, Annals of the New York Academy of Sciences.

[9]  G Westheimer,et al.  The ocular tilt reaction--a brainstem oculomotor routine. , 1975, Investigative ophthalmology.

[10]  G S Brindley,et al.  A case of ocular tilt reaction and torsional nystagmus due to direct stimulation of the midbrain in man. , 1991, Brain : a journal of neurology.

[11]  Torsional nystagmus. A neuro-otological and MRI study of thirty-five cases. , 1992, Brain : a journal of neurology.

[12]  W. Graf,et al.  A quantitative analysis of the spatial organization of the vestibulo-ocular reflexes in lateral- and frontal-eyed animals—II. Neuronal networks underlying vestibulo-oculomotor coordination , 1984, Neuroscience.

[13]  N. Barmack,et al.  A comparison of the horizontal and vertical vestibulo‐ocular reflexes of the rabbit , 1981, The Journal of physiology.

[14]  J. Keane.  Ocular skew deviation. Analysis of 100 cases. , 1975, Archives of neurology.

[15]  D. Tweed,et al.  Rotational kinematics of the human vestibuloocular reflex. I. Gain matrices. , 1994, Journal of neurophysiology.

[16]  S. Galetta,et al.  Ocular tilt reaction resulting from vestibuloacoustic nerve surgery. , 1993 .

[17]  T. Brandt,et al.  Wallenberg's syndrome: Lateropulsion, cyclorotation, and subjective visual vertical in thirty‐six patients , 1992, Annals of neurology.