To study the physiological and morphological relationships of two clover species affected by herbicides, Pursuit experiment in a factorial based on randomized completely design with 3 replications at the Damavand in 2012. The first factor consisted of two species of Trifolium pretense L. and Trifolium alexandrinum L. and the second factor consisted of three levels of herbicide...

OBJECTIVE To review the scientific literature about the relationship between impairment on smooth pursuit eye movements and schizophrenia. METHODS Narrative review that includes historical articles, reports about basic and clinical investigation, systematic reviews, and meta-analysis on the topic. RESULTS Up to 80% of schizophrenic patients have impairment of smooth pursuit eye movements. D...

We studied sinusoidal (SIN) and step-ramp (SR) pursuit in two rhesus monkeys, before and after surgical lesions of the cerebellar nodulus and uvula (Nod/Uv). Eye movements were recorded using the magnetic field scleral search coil method. Pursuit targets were generated by an LCD projector and back-projected onto a tangent screen in an otherwise dark room. After the Nod/Uv lesions, both monkeys ...

Missal, M. and S. J. Heinen. Supplementary eye fields stimulation facilitates anticipatory pursuit. J Neurophysiol 92: 1257–1262, 2004. First published March 10, 2004; 10.1152/jn.01255.2003. Anticipatory movements are motor responses occurring before likely sensory events in contrast to reflexive actions. Anticipatory movements are necessary to compensate for delays present in sensory and motor...

background: neurotologic signs and symptoms, especially vestibular symptoms are common in migrainous patients. involvement of the visual system in migrainures has received a great deal of attention in recent years, but the oculomotor part of the visual system has been largely ignored. the goal of this study was to investigate some parts of the central vestibular system using the oculomotor part...

Attention allocation during pursuit of a spot is usually characterized as asymmetric with more attention placed ahead of the target than behind it. However, attention is symmetrically allocated across larger pursuit stimuli. An unresolved issue is how tightly attention is constrained on large stimuli during pursuit. Although some work shows it is tightly locked to the fovea, other work shows it...

The translational vestibulo-ocular reflex (tVOR) stabilizes an image on the fovea during linear movements of the head. It has been suggested that the tVOR may share pathways with the pursuit system. We asked whether the tVOR and pursuit would be similar in their behavior relative to Listing's Law. We compared torsional eye velocity as a function of vertical orbital position during interaural tr...

The perception of unambiguous depth from motion parallax arises from the neural integration of retinal image motion and extra-retinal eye movement signals. It is only recently that these parameters have been articulated in the form of the motion/pursuit ratio. In the current study, we explored the lower limits of the parameter space in which observers could accurately perform near/far relative ...

Brief smooth eye-velocity responses to target position steps have been reported during smooth pursuit. We investigated position-error responses in eight healthy human subjects, comparing the effects of a step-ramp change in target position when imposed on steady-state smooth pursuit, vestibuloocular reflex (VOR) slow phases, or fixation. During steady-state pursuit or VOR, the target performed ...

Smooth pursuit eye movements are performed in order to prevent retinal image blur of a moving object. Rhesus monkeys are able to perform smooth pursuit eye movements quite similar as humans, even if the pursuit target does not consist in a simple moving dot. Therefore, the study of the neuronal responses as well as the consequences of micro-stimulation and lesions in trained monkeys performing ...