Abstract
Vestibular and optokinetic responses were recorded in three albino subjects with congenital nystagmus. Although an ice-water caloric stimulus did not elicit nystagmus, all patients showed a response to rotational stimuli containing high frequency components. Vestibular responses to a constant velocity rotation decremented with abnormally short time constants of 1-2 sec (normal 15-20 sec). For sinusoidal oscillation, in one subject, the cut-off frequency (where the amplitude of the response was 70% of maximum) was increased to 0.8 Hz (normal about 0.01 Hz). Full-field optokinetic stimulation generated no nystagmus response. These abnormalities may be due to defects in networks that act as mathematical integrators: either the final common neural gaze-holding network that converts velocity into position information for the ocular motor neurons or the 'velocity-storage' mechanism that normally combines sensory inputs from both the labyrinths and visual system to generate appropriate (per-rotatory) nystagmus during rotation and to suppress inappropriate (post-rotatory) nystagmus after rotation.
Original language | English (US) |
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Pages (from-to) | 739-745 |
Number of pages | 7 |
Journal | Investigative Ophthalmology and Visual Science |
Volume | 25 |
Issue number | 6 |
State | Published - 1984 |
ASJC Scopus subject areas
- Ophthalmology
- Sensory Systems
- Cellular and Molecular Neuroscience