The Arnold-Chiari malfomation is typically associated with downbeat nystagmus. Eye movement recordings in two patients with Arnold-Chiari malfomation type 1 showed, in addition to downbeat and gaze evoked nystagmus, intermittent nystagmus of skew. To date this finding has not been reported in association with Arnold-Chiari malfomation. Nystagmus of skew should raise the suspicion of Arnold-Chia...

Electrical stimulation in the monkey vestibulocerebellum has previously been shown to produce ocular nystagmus, but large stimulating current values were used. Using long duration (< or = 10-second) stimulus pulse trains and low current values (< 50 microA), we studied the nystagmus evoked by microstimulation in the uvular/nodular regions of the cerebellum. In doing this, we found quantitative ...

An extraordinary eye movement was seen in a vegetative patient. His eyeballs were exotropic in the primary position and showed dissociated nystagmus which appeared alternately in each eye every few seconds. He also had palatal myoclonus quite asynchronous with the nystagmus. To our knowledge, there has been no such nystagmus documented in the literature. We report the new nystagmus with his EOG...

The observation that the amplitude of ves­ tibular nystagmus grows as gaze is increased in the direction of the nystagmus fast phase and diminished with gaze in the opposite direction is known as "Alexander's law". We have developed an analog computer model to simulate Alexander's law in nys­ tagmus secondary to dysfunction of a semicircular canal. The model utilizes relevant brainstem anatomy ...

BACKGROUND Voluntary nystagmus has been recognized as a pendular, rapid, conjugate, primarily horizontal, benign eye movement initiated and maintained by voluntary effort. CASE A 10-year-old Japanese girl presented with voluntary nystagmus associated with accommodation spasms. Her chief complaints, intermittent blurred vision, headache, and soreness of the eyes, were thought to be related to ...

The ocular motor system consists of several subsystems, including the vestibular ocular nystagmus saccade system, the pursuit system, the fixation and gaze-holding system and the vergence system. All these subsystems aid the stabilization of the images on the retina during eye and head movements and any kind of disturbance of one of the systems can cause instability of the eyes (e.g. nystagmus)...

A survey of a college age population revealed that 8% could produce voluntary nystagmus. Seventy-nine per cent of this sample had relatives who could also produce it. A systematic investigation of the characteristics of voluntary nystagmus under a number of stimulus conditions showed that it resembles pendular nystagmus in waveform, and certain ocular oscillations, such as ocular flutter and op...

OBJECTIVE We wished to determine the effectiveness of horizontal rectus tenotomy in changing the nystagmus of patients with congenital nystagmus and, secondarily, how their visual function changed. DESIGN This was a prospective, noncomparative, interventional case series. PARTICIPANTS Ten adult patients with varied associated sensory defects and oculographic subtypes of congenital nystagmus...