PURPOSE Downbeat nystagmus (DBN) is a typical ocular motor sign in patients with lesions of the vestibulocerebellum. A vertical vestibular tone asymmetry, an upward shift of the eyes' null position for vertical gaze holding, or an imbalance of vertical smooth-pursuit signals have been proposed as mechanisms of DBN. The purpose of this study was to elaborate a possible link between an imbalance ...

Smooth pursuit eye movements have been linked to perception by a common attentional mechanism. We investigated whether perceptual performance was traded for smooth pursuit performance. While tracking a red target cross, observers had to discriminate the orientation of a flashed peripheral grating. We manipulated the priority given to the two tasks. Pursuit gain changed according to observers' e...

Monkeys generated disjunctive smooth pursuit eye movements when they tracked visual targets that moved toward or away from them. Eye acceleration was computed during the initial 100 msec of pursuit (the open-loop interval) for various target trajectories. The initial acceleration of either eye was a function of the target's motion with respect to that eye, regardless of whether or not the pursu...

In this study, how the state of eye movement before saccade affected the response to a stimulus was explored. The state of eye movement before saccade was either smooth pursuit or fixation. The smooth pursuit was carried out both clockwise and counter-clockwise. Using an eye-tracking system, the eye movement during the experimental task was monitored. The response time to a stimulus was measure...

Many studies indicate that saccades are necessarily preceded by a shift of attention to the target location. There is no direct evidence for the same coupling during smooth pursuit. If smooth pursuit and attention were coupled, pursuit onset should be delayed whenever attention is focused on a stationary, non-target location. To test this hypothesis, observers were instructed to shift their att...

PURPOSE Humans and monkeys are able to adapt their smooth pursuit output when challenged with consistent errors in foveal/parafoveal image motion during tracking. Visual motion information from the retina is known to be necessary for guiding smooth pursuit adaptation. The purpose of this study is to determine whether retinal motion signals delivered to one eye during smooth pursuit produce adap...

introduction: patients with bilateral weakness (bw) have many difficulties in gaze stability that interfere with their normal function. the aim of this study was to evaluate ocular motor functions in patients with bw to better understand the problem of gaze instability in these patients.   materials and methods: patients were referred from the otolaryngology department for vestibular assessment...

Although the roles of the basal ganglia in the control of saccadic eye movements have been extensively examined, little is known about their roles in smooth pursuit. Recent anatomical data suggest that, like somatic movements, smooth pursuit may also be regulated by signals through the basal ganglia thalamocortical pathways. To understand whether the basal ganglia, especially the globus pallidu...

Humans are very sensitive to the presence of other living persons or animals in their surrounding. Human actions can readily be perceived, even in a noisy environment. We recently demonstrated that biological motion, which schematically represents human motion, influences smooth pursuit eye movements during the initiation period (Orban de Xivry, Coppe, Lefèvre, & Missal, 2010). This smooth purs...