scholarly journals A Computational Model to Study the Dynamics of Updating of Remembered Visual Targets During Rapid and Slow Eye Movements

2015 ◽  
Vol 15 (12) ◽  
pp. 217 ◽  
Author(s):  
Yalda Mohsenzadeh ◽  
J. Crawford
Keyword(s):  
Eye Movements ◽  
Computational Model ◽  
Visual Targets ◽  
Slow Eye Movements

Visually evoked slow eye movements, visual-vestibular interaction, and infratentorial lesions

1983 ◽  
Vol 91 (1) ◽  
pp. 76-80 ◽  
Author(s):  
Carsten Wennmo ◽  
Nils Gunnar Henriksson ◽  
Bengt Hindfelt ◽  
Ilmari PyykkÖ ◽  
MÅNs Magnusson
Keyword(s):  
Eye Movements ◽  
Phase Velocity ◽  
Brain Stem ◽  
Smooth Pursuit ◽  
Maximum Velocity ◽  
Slow Phase ◽  
Slow Phase Velocity ◽  
Velocity Gain ◽  
Visual Vestibular Interaction ◽  
Slow Eye Movements

The maximum velocity gain of smooth pursuit and optokinetic, vestibular, and optovestibular slow phases was examined in 15 patients with pontine, 10 with medullary, 10 with cerebellar, and 5 with combined cerebello — brain stem disorders. Marked dissociations were observed between smooth pursuit and optokinetic slow phases, especially in medullary disease. A cerebellar deficit enhanced slow phase velocity gain during rotation in darkness, whereas the corresponding gain during rotation in light was normal.

Sensorimotor transformation during eye movements to remembered visual targets

1991 ◽  
Vol 31 (4) ◽  
pp. 693-715 ◽  
Author(s):  
James W. Gnadt ◽  
R. Martyn Bracewell ◽  
Richard A. Andersen
Keyword(s):  
Eye Movements ◽  
Sensorimotor Transformation ◽  
Visual Targets

scholarly journals Apparent Position of Visual Targets during Real and Simulated Saccadic Eye Movements

1997 ◽  
Vol 17 (20) ◽  
pp. 7941-7953 ◽  
Author(s):  
M. Concetta Morrone ◽  
John Ross ◽  
David C. Burr
Keyword(s):  
Eye Movements ◽  
Saccadic Eye Movements ◽  
Apparent Position ◽  
Visual Targets

Contribution of the Cerebellar Flocculus to Gaze Control during Active Head Movements

1999 ◽  
Vol 81 (6) ◽  
pp. 3105-3109 ◽  
Author(s):  
T. Belton ◽  
R. A. McCrea
Keyword(s):  
Eye Movements ◽  
Cerebellar Cortex ◽  
Smooth Pursuit ◽  
Head Movements ◽  
Gaze Control ◽  
Smooth Pursuit Eye Movements ◽  
Ocular Pursuit ◽  
Pursuit Eye Movements ◽  
Cerebellar Flocculus ◽  
Visual Targets

Contribution of the cerebellar flocculus to gaze control during active head movements. The flocculus and ventral paraflocculus are adjacent regions of the cerebellar cortex that are essential for controlling smooth pursuit eye movements and for altering the performance of the vestibulo-ocular reflex (VOR). The question addressed in this study is whether these regions of the cerebellum are more globally involved in controlling gaze, regardless of whether eye or active head movements are used to pursue moving visual targets. Single-unit recordings were obtained from Purkinje (Pk) cells in the floccular region of squirrel monkeys that were trained to fixate and pursue small visual targets. Cell firing rate was recorded during smooth pursuit eye movements, cancellation of the VOR, combined eye-head pursuit, and spontaneous gaze shifts in the absence of targets. Pk cells were found to be much less sensitive to gaze velocity during combined eye–head pursuit than during ocular pursuit. They were not sensitive to gaze or head velocity during gaze saccades. Temporary inactivation of the floccular region by muscimol injection compromised ocular pursuit but had little effect on the ability of monkeys to pursue visual targets with head movements or to cancel the VOR during active head movements. Thus the signals produced by Pk cells in the floccular region are necessary for controlling smooth pursuit eye movements but not for coordinating gaze during active head movements. The results imply that individual functional modules in the cerebellar cortex are less involved in the global organization and coordination of movements than with parametric control of movements produced by a specific part of the body.

scholarly journals Continuous Updating of Visuospatial Memory in Superior Colliculus during Slow Eye Movements

2015 ◽  
Vol 25 (3) ◽  
pp. 267-274 ◽  
Author(s):  
Suryadeep Dash ◽  
Xiaogang Yan ◽  
Hongying Wang ◽  
John Douglas Crawford
Keyword(s):  
Eye Movements ◽  
Superior Colliculus ◽  
Visuospatial Memory ◽  
Slow Eye Movements

scholarly journals Pursuit disorder and saccade dysmetria after caudal fastigial inactivation in the monkey

2018 ◽  
Vol 120 (4) ◽  
pp. 1640-1654 ◽  
Author(s):  
Clara Bourrelly ◽  
Julie Quinet ◽  
Laurent Goffart
Keyword(s):  
Eye Movements ◽  
Eye Movement ◽  
Visual Target ◽  
Fastigial Nucleus ◽  
Gaze Direction ◽  
Moving Target ◽  
Horizontal Meridian ◽  
Pursuit Eye Movements ◽  
Neural Processes ◽  
Slow Eye Movements

The caudal fastigial nuclei (cFN) are the output nuclei by which the medio-posterior cerebellum influences the production of saccadic and pursuit eye movements. We investigated the consequences of unilateral inactivation on the pursuit eye movement made immediately after an interceptive saccade toward a centrifugal target. We describe here the effects when the target moved along the horizontal meridian with a 10 or 20°/s speed. After muscimol injection, the monkeys were unable to track the present location of the moving target. During contralesional tracking, the velocity of postsaccadic pursuit was reduced. This slowing was associated with a hypometria of interceptive saccades such that gaze direction always lagged behind the moving target. No correlation was found between the sizes of saccade undershoot and the decreases in pursuit speed. During ipsilesional tracking, the effects on postsaccadic pursuit were variable across the injection sessions, whereas the interceptive saccades were consistently hypermetric. Here also, the ipsilesional pursuit disorder was not correlated with the saccade hypermetria either. The lack of correlation between the sizes of saccade dysmetria and changes of postsaccadic pursuit speed suggests that cFN activity exerts independent influences on the neural processes generating the saccadic and slow eye movements. It also suggests that the cFN is one locus where the synergy between the two motor categories develops in the context of tracking a moving visual target. We explain how the different fastigial output channels can account for these oculomotor tracking disorders. NEW & NOTEWORTHY Inactivation of the caudal fastigial nucleus impairs the ability to track a moving target. The accuracy of interceptive saccades and the velocity of postsaccadic pursuit movements are both altered, but these changes are not correlated. This absence of correlation is not compatible with an impaired common command feeding the circuits producing saccadic and pursuit eye movements. However, it suggests an involvement of caudal fastigial nuclei in their synergy to accurately track a moving target.

Sign in / Sign up

Export Citation Format

Share Document