Extraretinal Signals in MSTd Neurons Related to Volitional Smooth Pursuit

2006 ◽  
Vol 96 (5) ◽  
pp. 2819-2825 ◽  
Author(s):  
Seiji Ono ◽  
Michael J. Mustari
Keyword(s):  
Eye Movements ◽  
Smooth Pursuit ◽  
Temporal Cortex ◽  
Vestibular Stimulation ◽  
Neuronal Firing ◽  
Target Velocity ◽  
Ocular Reflex ◽  
Medial Superior Temporal ◽  
Vestibular Ocular Reflex ◽  
Pursuit Neurons

Smooth pursuit (SP)-related neurons in the dorsal-medial part of medial superior temporal cortex (MSTd) carry extraretinal signals that may play a role in maintenance of SP once eye velocity matches target velocity. For example, it has not been determined whether the extraretinal signals reflect volitional SP commands or proprioception. The aim of this study was to test some potential sources of extraretinal signals in MSTd pursuit neurons. We tested 40 MSTd neurons during step-ramp SP with target blink conditions to show that they carried an extraretinal signal. To examine potential contributions from eye movements that might reflect proprioceptive feedback from eye muscles, we tested MSTd neurons during rotational vestibular ocular reflex in complete darkness (VORd). Vestibular stimulation was delivered in the earth horizontal plane to elicit reflex driven smooth eye movements that matched the speed and frequency of volitional SP. We also tested VOR in the light (VORx1) and cancellation of the VOR (VORx0). Our neurons were modulated during both SP and cancellation of the VOR. In contrast, MSTd smooth pursuit neurons with extraretinal signals were not significantly modulated during VORd (sensitivity ≤ 0.10 spike/s/°/s). This combination of properties is compatible with classifying these neurons as gaze-velocity related. Absence of modulation during VORd testing could be caused by cancellation of head and eye movement sensitivity or dependence of neuronal firing on volitional SP commands. Our results support the suggestion that modulation of SP-related MSTd neurons reflects volitional SP commands rather then eye movements generated by reflex pathways.

scholarly journals The vestibular-related frontal cortex and its role in smooth-pursuit eye movements and vestibular-pursuit interactions

2006 ◽  
Vol 16 (1-2) ◽  
pp. 1-22 ◽  
Author(s):  
Junko Fukushima ◽  
Teppei Akao ◽  
Sergei Kurkin ◽  
Chris R.S. Kaneko ◽  
Kikuro Fukushima
Keyword(s):  
Eye Movements ◽  
Frontal Cortex ◽  
Smooth Pursuit ◽  
Vestibular Stimulation ◽  
Target Motion ◽  
Head Movements ◽  
Image Motion ◽  
Target Velocity ◽  
Eye Velocity ◽  
Pursuit Neurons

In order to see clearly when a target is moving slowly, primates with high acuity foveae use smooth-pursuit and vergence eye movements. The former rotates both eyes in the same direction to track target motion in frontal planes, while the latter rotates left and right eyes in opposite directions to track target motion in depth. Together, these two systems pursue targets precisely and maintain their images on the foveae of both eyes. During head movements, both systems must interact with the vestibular system to minimize slip of the retinal images. The primate frontal cortex contains two pursuit-related areas; the caudal part of the frontal eye fields (FEF) and supplementary eye fields (SEF). Evoked potential studies have demonstrated vestibular projections to both areas and pursuit neurons in both areas respond to vestibular stimulation. The majority of FEF pursuit neurons code parameters of pursuit such as pursuit and vergence eye velocity, gaze velocity, and retinal image motion for target velocity in frontal and depth planes. Moreover, vestibular inputs contribute to the predictive pursuit responses of FEF neurons. In contrast, the majority of SEF pursuit neurons do not code pursuit metrics and many SEF neurons are reported to be active in more complex tasks. These results suggest that FEF- and SEF-pursuit neurons are involved in different aspects of vestibular-pursuit interactions and that eye velocity coding of SEF pursuit neurons is specialized for the task condition.

scholarly journals A neuroanatomically grounded optimal control model of the compensatory eye movement system

2019 ◽  
Author(s):  
P.J. Holland ◽  
T.M. Sibindi ◽  
M. Ginzburg ◽  
S. Das ◽  
K. Arkesteijn ◽  
...  
Keyword(s):  
Eye Movements ◽  
Eye Movement ◽  
Visual Stimulation ◽  
Vestibular Stimulation ◽  
Data Set ◽  
Ocular Reflex ◽  
State Prediction ◽  
Vestibular Ocular Reflex ◽  
Vor Adaptation ◽  
Movement System

AbstractWe present a working model of the compensatory eye movement system. We challenge the model with a data set of eye movements in mice (n=34) recorded in 4 different sinusoidal stimulus conditions with 36 different combinations of frequency (0.1-3.2 Hz) and amplitude (0.5-8°) in each condition. The conditions included vestibular stimulation in the dark (vestibular-ocular reflex, VOR), optokinetic stimulation (optokinetic reflex, OKR), and two combined visual/vestibular conditions (the visual-vestibular ocular reflex, vVOR, and visual suppression of the VOR, sVOR). The model successfully reproduced the eye movements in all conditions, except for minor failures to predict phase when gain was very low. Most importantly, it could explain the non-linear summation of VOR and OKR when the two reflexes are activated simultaneously during vVOR stimulation. In addition to our own data, we also reproduced the behavior of the compensatory eye movement system found in the existing literature. These include its response to sum-of-sines stimuli, its response after lesions of the nucleus prepositus hypoglossi or the flocculus, characteristics of VOR adaptation, and characteristics of drift in the dark. Our model is based on ideas of state prediction and forward modeling that have been widely used in the study of motor control. However, it represents one of the first quantitative efforts to simulate the full range of behaviors of a specific system. The model has two separate processing loops, one for vestibular stimulation and one for visual stimulation. Importantly, state prediction in the visual processing loop depends on a forward model of residual retinal slip after vestibular processing. In addition, we hypothesize that adaptation in the system is primarily adaptation of this model. In other words, VOR adaptation happens primarily in the OKR loop.

Premorbid migraine history as a risk factor for vestibular and oculomotor baseline concussion assessment in pediatric athletes

2019 ◽  
Vol 23 (4) ◽  
pp. 465-470 ◽  
Author(s):  
Ryan N. Moran ◽  
Tracey Covassin ◽  
Jessica Wallace
Keyword(s):  
Risk Factor ◽  
Smooth Pursuit ◽  
Migraine Headache ◽  
Visual Motion ◽  
Assessment Tools ◽  
Motion Sensitivity ◽  
Ocular Reflex ◽  
Migraine Headaches ◽  
Vestibular Ocular Reflex ◽  
History Of

OBJECTIVEMigraine history has recently been identified as a risk factor for concussion and recovery. The authors performed a cross-sectional study examining baseline outcome measures on newly developed and implemented concussion assessment tools in pediatrics. The purpose of this study was to examine the effects of premorbid, diagnosed migraine headaches as a risk factor on vestibular and oculomotor baseline assessment in pediatric athletes.METHODSPediatric athletes between the ages of 8 and 14 years with a diagnosed history of migraine headache (n = 28) and matched controls without a history of diagnosed migraine headache (n = 28) were administered a baseline concussion assessment battery, consisting of the Vestibular/Ocular Motor Screening (VOMS), near point of convergence (NPC), and the King-Devick (K-D) tests. Between-groups comparisons were performed for vestibular symptoms and provocation scores on the VOMS (smooth pursuit, saccades, convergence, vestibular/ocular reflex, visual motion sensitivity), NPC (average distance), and K-D (time).RESULTSIndividuals diagnosed with migraine headaches reported greater VOMS smooth pursuit scores (p = 0.02), convergence scores (p = 0.04), vestibular ocular reflex scores (p value range 0.002–0.04), and visual motion sensitivity scores (p = 0.009). Differences were also observed on K-D oculomotor performance with worse times in those diagnosed with migraine headache (p = 0.02). No differences were reported on NPC distance (p = 0.06) or headache symptom reporting (p = 0.07) prior to the VOMS assessment.CONCLUSIONSPediatric athletes diagnosed with migraine headaches reported higher baseline symptom provocation scores on the VOMS. Athletes with migraine headaches also performed worse on the K-D test, further illustrating the influence of premorbid migraine headaches as a risk factor for elevated concussion assessment outcomes at baseline. Special consideration may be warranted for post-concussion assessment in athletes with migraine headaches.

scholarly journals Role of Primate Cerebellar Hemisphere in Voluntary Eye Movement Control Revealed by Lesion Effects

2009 ◽  
Vol 101 (2) ◽  
pp. 934-947 ◽  
Author(s):  
Masafumi Ohki ◽  
Hiromasa Kitazawa ◽  
Takahito Hiramatsu ◽  
Kimitake Kaga ◽  
Taiko Kitamura ◽  
...  
Keyword(s):  
Eye Movements ◽  
Eye Movement ◽  
Smooth Pursuit ◽  
Movement Control ◽  
Cerebellar Hemisphere ◽  
Target Velocity ◽  
Eye Movement Control ◽  
Pursuit Eye Movements ◽  
Catch Up

The anatomical connection between the frontal eye field and the cerebellar hemispheric lobule VII (H-VII) suggests a potential role of the hemisphere in voluntary eye movement control. To reveal the involvement of the hemisphere in smooth pursuit and saccade control, we made a unilateral lesion around H-VII and examined its effects in three Macaca fuscata that were trained to pursue visually a small target. To the step (3°)-ramp (5–20°/s) target motion, the monkeys usually showed an initial pursuit eye movement at a latency of 80–140 ms and a small catch-up saccade at 140–220 ms that was followed by a postsaccadic pursuit eye movement that roughly matched the ramp target velocity. After unilateral cerebellar hemispheric lesioning, the initial pursuit eye movements were impaired, and the velocities of the postsaccadic pursuit eye movements decreased. The onsets of 5° visually guided saccades to the stationary target were delayed, and their amplitudes showed a tendency of increased trial-to-trial variability but never became hypo- or hypermetric. Similar tendencies were observed in the onsets and amplitudes of catch-up saccades. The adaptation of open-loop smooth pursuit velocity, tested by a step increase in target velocity for a brief period, was impaired. These lesion effects were recognized in all directions, particularly in the ipsiversive direction. A recovery was observed at 4 wk postlesion for some of these lesion effects. These results suggest that the cerebellar hemispheric region around lobule VII is involved in the control of smooth pursuit and saccadic eye movements.

Evidence for a retinal velocity memory underlying the direction of anticipatory smooth pursuit eye movements

2013 ◽  
Vol 110 (3) ◽  
pp. 732-747 ◽  
Author(s):  
T. Scott Murdison ◽  
Chanel A. Paré-Bingley ◽  
Gunnar Blohm
Keyword(s):  
Eye Movements ◽  
Smooth Pursuit ◽  
Target Velocity ◽  
Smooth Pursuit Eye Movements ◽  
Ocular Torsion ◽  
Pursuit Eye Movements ◽  
Ocular Counterroll ◽  
In Series ◽  
Head Roll ◽  
Directional Component

To compute spatially correct smooth pursuit eye movements, the brain uses both retinal motion and extraretinal signals about the eyes and head in space ( Blohm and Lefèvre 2010 ). However, when smooth eye movements rely solely on memorized target velocity, such as during anticipatory pursuit, it is unknown if this velocity memory also accounts for extraretinal information, such as head roll and ocular torsion. To answer this question, we used a novel behavioral updating paradigm in which participants pursued a repetitive, spatially constant fixation-gap-ramp stimulus in series of five trials. During the first four trials, participants' heads were rolled toward one shoulder, inducing ocular counterroll (OCR). With each repetition, participants increased their anticipatory pursuit gain, indicating a robust encoding of velocity memory. On the fifth trial, they rolled their heads to the opposite shoulder before pursuit, also inducing changes in ocular torsion. Consequently, for spatially accurate anticipatory pursuit, the velocity memory had to be updated across changes in head roll and ocular torsion. We tested how the velocity memory accounted for head roll and OCR by observing the effects of changes to these signals on anticipatory trajectories of the memory decoding (fifth) trials. We found that anticipatory pursuit was updated for changes in head roll; however, we observed no evidence of compensation for OCR, representing the absence of ocular torsion signals within the velocity memory. This indicated that the directional component of the memory must be coded retinally and updated to account for changes in head roll, but not OCR.

scholarly journals Functional specialization in the middle temporal area for smooth pursuit initiation

2019 ◽  
Vol 2 ◽  
pp. 6 ◽  
Author(s):  
Shahab Bakhtiari ◽  
Christopher C. Pack
Keyword(s):  
Eye Movements ◽  
Smooth Pursuit ◽  
Sensory Information ◽  
Target Velocity ◽  
Multiple Sources ◽  
Temporal Area ◽  
Middle Temporal ◽  
Mt Neurons ◽  
Pursuit Eye Movements ◽  
Pursuit Initiation

Smooth pursuit eye movements have frequently been used to model sensorimotor transformations in the brain. In particular, the initiation phase of pursuit can be understood as a transformation of a sensory estimate of target velocity into an eye rotation. Despite careful laboratory controls on the stimulus conditions, pursuit eye movements are frequently observed to exhibit considerable trial-to-trial variability. In theory, this variability can be caused by the variability in sensory representation of target motion, or by the variability in the transformation of sensory information to motor commands. Previous work has shown that neural variability in the middle temporal (MT) area is likely propagated to the oculomotor command, and there is evidence to suggest that the magnitude of this variability is sufficient to account for the variability of pursuit initiation. This line of reasoning presumes that the MT population is homogeneous with respect to its contribution to pursuit initiation.  At the same time, there is evidence that pursuit initiation is strongly linked to a subpopulation of MT neurons (those with strong surround suppression) that collectively generate less motor variability. To distinguish between these possibilities, we have combined human psychophysics, monkey electrophysiology, and computational modeling to examine how the pursuit system reads out the MT population during pursuit initiation. We find that the psychophysical data are best accounted for by a model that gives stronger weight to surround-suppressed MT neurons, suggesting that variability in the initiation of pursuit could arise from multiple sources along the sensorimotor transformation.

scholarly journals Comparison between Passively Evoked Smooth Pursuit Eye Movements and Optokinetic Ocular Reflex.

1997 ◽  
Vol 56 (5) ◽  
pp. 444-453
Author(s):  
Motoyuki Hashiba ◽  
Teruaki Hattori ◽  
Nobuhiro Watanabe ◽  
Shunkichi Baba ◽  
Hirotaka Watabe ◽  
...  
Keyword(s):  
Eye Movements ◽  
Smooth Pursuit ◽  
Smooth Pursuit Eye Movements ◽  
Pursuit Eye Movements ◽  
Ocular Reflex

scholarly journals Evidence for Object Permanence in the Smooth-Pursuit Eye Movements of Monkeys

2003 ◽  
Vol 90 (4) ◽  
pp. 2205-2218 ◽  
Author(s):  
Mark M. Churchland ◽  
I-Han Chou ◽  
Stephen G. Lisberger
Keyword(s):  
Steady State ◽  
Eye Movements ◽  
Computer Simulations ◽  
Smooth Pursuit ◽  
Constant Velocity ◽  
Object Permanence ◽  
Target Velocity ◽  
Smooth Pursuit Eye Movements ◽  
Pursuit Eye Movements ◽  
Eye Velocity

We recorded the smooth-pursuit eye movements of monkeys in response to targets that were extinguished (blinked) for 200 ms in mid-trajectory. Eye velocity declined considerably during the target blinks, even when the blinks were completely predictable in time and space. Eye velocity declined whether blinks were presented during steady-state pursuit of a constant-velocity target, during initiation of pursuit before target velocity was reached, or during eye accelerations induced by a change in target velocity. When a physical occluder covered the trajectory of the target during blinks, creating the impression that the target moved behind it, the decline in eye velocity was reduced or abolished. If the target was occluded once the eye had reached target velocity, pursuit was only slightly poorer than normal, uninterrupted pursuit. In contrast, if the target was occluded during the initiation of pursuit, while the eye was accelerating toward target velocity, pursuit during occlusion was very different from normal pursuit. Eye velocity remained relatively stable during target occlusion, showing much less acceleration than normal pursuit and much less of a decline than was produced by a target blink. Anticipatory or predictive eye acceleration was typically observed just prior to the reappearance of the target. Computer simulations show that these results are best understood by assuming that a mechanism of eye-velocity memory remains engaged during target occlusion but is disengaged during target blinks.

scholarly journals Enhancement of the Vestibulo-Ocular Reflex by Prior Eye Movements

1999 ◽  
Vol 81 (6) ◽  
pp. 2884-2892 ◽  
Author(s):  
Vallabh E. Das ◽  
Louis F. Dell’Osso ◽  
R. John Leigh
Keyword(s):  
Eye Movements ◽  
Smooth Pursuit ◽  
Initial Perturbation ◽  
Head Rotation ◽  
Gaze Shift ◽  
Stationary Target ◽  
Ocular Reflex ◽  
Vestibulo Ocular Reflex ◽  
Head Rotations ◽  
Horizontal Head

Enhancement of the vestibulo-ocular reflex by prior eye movements. We investigated the effect of visually mediated eye movements made before velocity-step horizontal head rotations in eleven normal human subjects. When subjects viewed a stationary target before and during head rotation, gaze velocity was initially perturbed by ∼20% of head velocity; gaze velocity subsequently declined to zero within ∼300 ms of the stimulus onset. We used a curve-fitting procedure to estimate the dynamic course of the gain throughout the compensatory response to head rotation. This analysis indicated that the median initial gain of compensatory eye movements (mainly because of the vestibulo-ocular reflex, VOR) was 0.8 and subsequently increased to 1.0 after a median interval of 320 ms. When subjects attempted to fixate the remembered location of the target in darkness, the initial perturbation of gaze was similar to during fixation of a visible target (median initial VOR gain 0.8); however, the period during which the gain increased toward 1.0 was >10 times longer than that during visual fixation. When subjects performed horizontal smooth-pursuit eye movements that ended (i.e., 0 gaze velocity) just before the head rotation, the gaze velocity perturbation at the onset of head rotation was absent or small. The initial gain of the VOR had been significantly increased by the prior pursuit movements for all subjects ( P < 0.05; mean increase of 11%). In four subjects, we determined that horizontal saccades and smooth tracking of a head-fixed target (VOR cancellation with eye stationary in the orbit) also increased the initial VOR gain (by a mean of 13%) during subsequent head rotations. However, after vertical saccades or smooth pursuit, the initial gaze perturbation caused by a horizontal head rotation was similar to that which occurred after fixation of a stationary target. We conclude that the initial gain of the VOR during a sudden horizontal head rotation is increased by prior horizontal, but not vertical, visually mediated gaze shifts. We postulate that this “priming” effect of a prior gaze shift on the gain of the VOR occurs at the level of the velocity inputs to the neural integrator subserving horizontal eye movements, where gaze-shifting commands and vestibular signals converge.

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