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The purpose of this study was to assess the vestibular and oculomotor function in patients with vestibular migraine (VM). And we also investigate the relationship between testing results and effectiveness of preventive medications in VM.41 patients with VM were recruited in this study and examined with cervical and ocular vestibular evoked myogenic potential(cVEMP, oVEMP), video head impulse test(vHIT), caloric test and videonystagmography. All patients were treated with preventive medications. We calculated symptomatic improvement and record episodes frequency in patients with VM. Six months later, the effectiveness of preventive medications were evaluated and the relationship between vestibular testing and effectiveness of preventive medications were analyzed further.In vestibular function testing, 73% of patients with VM showed abnormal results. Abnormal cVEMP, oVEMP, vHIT, and caloric test were found in 20%, 44%, 32% and 56% respectively. The abnormal rate of oVEMP was significantly higher than that of cVEMP(p 0.05). And the proportion of abnormal caloric test was obviously higher than that of vHIT (p 0.05). In oculomotor function testing, 42% of the patients with VM showed pathological results which was significantly lower than that of vestibular function testing(p 0.05). After 6 months follow-up, the proportion of prophylactic medication effectiveness was significantly higher in normal vestibular function testing group compared with the abnormal group (p 0.05).Abnormal vestibular and oculomotor functions are commonly observed in patients with VM. And these patients with abnormal vestibular function possess a weak effectiveness of preventive medications.

Persons with Parkinson disease (PD) experience turning difficulty, often leading to freezing of gait and falls. Visual information plays a significant role in locomotion and turning, and while the effects of deep brain stimulation (DBS) on oculomotor function have been well documented, the effects of DBS on oculomotor function during turning and on turning itself have yet to be fully elucidated.To determine the effects of STN DBS on turning performance and related oculomotor performance in PD.Eleven subjects with PD and DBS of the subthalamic nucleus performed a seated voluntary saccade task and standing 180° turns in DBS OFF and DBS ON conditions. Oculomotor data were captured using an infrared eye tracking system while segment rotations were measured using 3-D motion capture.During the seated saccade task, DBS did not improve saccade amplitude or latency. DBS also did not improve gait velocity and stride length during forward walking. During turning, DBS improved turn performance (turn duration), reduced the number of saccades performed during the turns, and increased the amplitude and velocity of the saccade initiating the turn. DBS decreased the intersegmental latencies (eye-head, eye-foot, and head-trunk) but this effect was lost for eye-head and eye-foot after controlling for the duration of the first gait cycle.DBS significantly improves turn performance and related oculomotor performance. These findings add to the growing list of therapeutic benefits offered by DBS.

The background, theories, and observations on visual stress possibly caused by viewing stereoscopic motion images are reviewed. Visual fatigue caused by stereoscopic images is a safety issue. Fatigue is possible caused by the discrepancy between accommodative and convergence stimuli that are included in the image. Studies on accommodation and convergence are surveyed and an explanation regarding the characteristics of these functions is offered. Studies in the literature on changes in oculomotor function after viewing stereoscopic images, including changes in pupillary responses, are discussed. Evaluation of visual fatigue, particularly in relation to different methods of viewing stereoscopic displays is described.

Monkeys were tested on a battery of visual discrimination problems before and after aspiration lesions of the superior colliculi. Additional animals were given striate cortex ablations prior to or simultaneous with ablations of the colliculi, and tested before and after the combined lesions and interoperatively where possible. The results confirm earlier findings that collicular ablation produces no deficit in oculomotor function in alert monkeys, and further demonstrate that there are no impairements on formal tests of total flux, flicker, pattern, color, or visual movement detection discriminations. Collicular destruction does result in a reliable impairement of rate discrimination, however, which in the 7 animals studied was subject to considerable recovery. Prior and simultaneous partial striate cortex lesions potentiate these deficits severely and to the same degree. Complete striate ablations alone produce severe and well known visual impairments which do not, however, include significant impairment of flicker discrimination or CFF threshold. Addition of collicular ablation does abolish the capacity for a simple flicker discrimination, but even these severely impaired animals are capable of differential responses to changes in total luminous flux.

Rhesus monkeys were trained to track a moving disk using a procedure in which responses on a lever were reinforced with water delivery only when the disk, oscillating in a horizontal plane on a screen at a frequency of 0.4 Hz in a visual angle of 20°, dimmed for a brief period. Pursuit eye-movements were recorded by electro-oculography (EOG). Intramuscular phencyclidine, secobarbital and diazepam injections decreased the number of reinforced lever-presses in a dose-related manner. Phencyclidine produced catatonic staring at least in one monkey, while secobarbital and diazepam produced episodic jerky pursuit eye-movements. Disruptions of lever-pressing behavior and smooth pursuit eye-movements were not always correlated. The similarities of the drug effects on smooth pursuit eye-movements between the present study and human studies indicate that the present method using rhesus monkeys may be useful for predicting drug effects on eye-tracking and oculomotor function in humans.