Visual signals in the dorsolateral pontine nucleus of the alert monkey: Their relationship to smooth-pursuit eye movements

1984 ◽  
Vol 53 (2) ◽  
Author(s):  
D.A. Suzuki ◽  
E.L. Keller
Keyword(s):  
Eye Movements ◽  
Smooth Pursuit ◽  
Visual Signals ◽  
Smooth Pursuit Eye Movements ◽  
Alert Monkey ◽  
Pontine Nucleus ◽  
Pursuit Eye Movements ◽  
Dorsolateral Pontine Nucleus

Smooth-Pursuit Eye-Movement Deficits With Chemical Lesions in Macaque Nucleus Reticularis Tegmenti Pontis

1999 ◽  
Vol 82 (3) ◽  
pp. 1178-1186 ◽  
Author(s):  
David A. Suzuki ◽  
Tetsuto Yamada ◽  
Rebecca Hoedema ◽  
Robert D. Yee
Keyword(s):  
Eye Movements ◽  
Smooth Pursuit ◽  
Ibotenic Acid ◽  
Frontal Eye Field ◽  
Smooth Pursuit Eye Movements ◽  
Pontine Nucleus ◽  
Nucleus Reticularis Tegmenti Pontis ◽  
Pursuit Eye Movements ◽  
Nucleus Reticularis ◽  
Dorsolateral Pontine Nucleus

Anatomic and neuronal recordings suggest that the nucleus reticularis tegmenti pontis (NRTP) of macaques may be a major pontine component of a cortico-ponto-cerebellar pathway that subserves the control of smooth-pursuit eye movements. The existence of such a pathway was implicated by the lack of permanent pursuit impairment after bilateral lesions in the dorsolateral pontine nucleus. To provide more direct evidence that NRTP is involved with regulating smooth-pursuit eye movements, chemical lesions were made in macaque NRTP by injecting either lidocaine or ibotenic acid. Injection sites first were identified by the recording of smooth-pursuit-related modulations in neuronal activity. The resulting lesions caused significant deficits in both the maintenance and the initiation of smooth-pursuit eye movements. After lesion formation, the gain of constant-velocity, maintained smooth-pursuit eye movements decreased, on the average, by 44%. Recovery of the ability to maintain smooth-pursuit eye movements occurred over ∼3 days when maintained pursuit gains attained normal values. The step-ramp, “Rashbass” task was used to investigate the effects of the lesions on the initiation of smooth-pursuit eye movements. Eye accelerations averaged over the initial 80 ms of pursuit initiation were determined and found to be decremented, on the average, by 48% after the administration of ibotenic acid. Impairments in the initiation and maintenance of smooth-pursuit eye movements were directional in nature. Upward pursuit seemed to be the most vulnerable and was impaired in all cases independent of lesioning agent and type of pursuit investigated. Downward smooth pursuit seemed more resistant to the effects of chemical lesions in NRTP. Impairments in horizontal tracking were observed with examples of deficits in ipsilaterally and contralaterally directed pursuit. The results provide behavioral support for the physiologically and anatomic-based conclusion that NRTP is a component of a cortico-ponto-cerebellar circuit that presumably involves the pursuit area of the frontal eye field (FEF) and projects to ocular motor-related areas of the cerebellum. This FEF-NRTP-cerebellum path would parallel a middle and medial superior temporal cerebral cortical area-dorsolateral pontine nucleus-cerebellum pathway also known to be involved with regulating smooth-pursuit eye movements.

Smooth-pursuit eye movement deficits with chemical lesions in the dorsolateral pontine nucleus of the monkey

1988 ◽  
Vol 59 (3) ◽  
pp. 952-977 ◽  
Author(s):  
J. G. May ◽  
E. L. Keller ◽  
D. A. Suzuki
Keyword(s):  
Steady State ◽  
Eye Movements ◽  
Smooth Pursuit ◽  
Visual Motion ◽  
Ibotenic Acid ◽  
Smooth Pursuit Eye Movements ◽  
Optokinetic Response ◽  
Pontine Nucleus ◽  
Pursuit Eye Movements ◽  
Dorsolateral Pontine Nucleus

1. Anatomical and single-unit recording studies suggest that the dorsolateral pontine nucleus (DLPN) in monkey is a major link in the projection of descending visual motion information to the cerebellum. Such studies coupled with cortical and cerebellar lesion results suggest a major role for this basilar pontine region in the mediation of smooth-pursuit eye movements. 2. To provide more direct evidence that this pontine region is involved in the control of smooth-pursuit eye movements, focal chemical lesions were made in DLPN in the vicinity of previously recorded visual motion and pursuit-related neurons. Eye movement responses were subsequently recorded in these lesioned animals under several behavioral paradigms. 3. A major deficit in smooth-pursuit performance was produced after unilateral DLPN lesions generated either reversibly with lidocaine or more permanently with ibotenic acid. Pursuit impairments were observed during steady-state tracking of sinusoidal target motion as well as during the initiation of pursuit tracking to sudden ramp target motion. Through the use of the latter technique, initial eye acceleration was reduced to less than one-half of normal for animals with large lesions of the dorsolateral and lateral pontine nuclei. 4. The pursuit deficit in all animals was directional in nature and was not dependent on the visual hemifield in which the motion stimulus occurred. The largest effect for horizontal tracking occurred in all animals for pursuit directed ipsilateral to the lesion. Animals also showed major deficits in one or both directions of vertical pursuit, although the primary direction of the vertical impairment was variable from animal to animal. 5. Chemical lesions in the DLPN also produced comparable deficits in the initiation of optokinetic-induced smooth eye movements in the ipsilateral direction. In contrast to this effect on the initial optokinetic response, in the one lesioned animal studied during prolonged constant velocity optokinetic drum rotation, smooth eye speed increased slowly over a 10- to 15-s period to reach a level that closely matched drum speed. These results suggest that pathways outside the DLPN can generate the steady-state optokinetic response. 6. Saccades to stationary targets were normal after DLPN lesions, but corrective saccades made to targets moving in the direction ipsilateral to the lesion were much more hypometric than similar prelesion control saccades. 7. The pursuit deficits produced by lidocaine injections recovered within 30 min. The ibotenic acid deficits were maximal approximately 1 day after the injection and recovered rapidly thereafter over a time period of 3-7 days.(ABSTRACT TRUNCATED AT 400 WORDS)

A Control Systems Model of Smooth Pursuit Eye Movements with Realistic Emergent Properties

1989 ◽  
Vol 1 (1) ◽  
pp. 116-122 ◽  
Author(s):  
R. J. Krauzlis ◽  
S. G. Lisberger
Keyword(s):  
Eye Movements ◽  
Visual Tracking ◽  
Smooth Pursuit ◽  
Oculomotor System ◽  
Difficult Problem ◽  
Visual Signals ◽  
Emergent Properties ◽  
Smooth Pursuit Eye Movements ◽  
Pursuit Eye Movements ◽  
Systems Model

Visual tracking of objects in a noisy environment is a difficult problem that has been solved by the primate oculomotor system, but remains unsolved in robotics. In primates, smooth pursuit eye movements match eye motion to target motion to keep the eye pointed at smoothly moving targets. We have used computer models as a tool to investigate possible computational strategies underlying this behavior. Here, we present a model based upon behavioral data from monkeys. The model emphasizes the variety of visual signals available for pursuit and, in particular, includes a sensitivity to the acceleration of retinal images. The model was designed to replicate the initial eye velocity response observed during pursuit of different target motions. The strength of the model is that it also exhibits a number of emergent properties that are seen in the behavior of both humans and monkeys. This suggests that the elements in the model capture important aspects of the mechanism of visual tracking by the primate smooth pursuit system.

Smooth pursuitlike eye movements evoked by microstimulation in macaque nucleus reticularis tegmenti pontis

1996 ◽  
Vol 76 (5) ◽  
pp. 3313-3324 ◽  
Author(s):  
T. Yamada ◽  
D. A. Suzuki ◽  
R. D. Yee
Keyword(s):  
Eye Movements ◽  
Smooth Pursuit ◽  
Current Intensity ◽  
Image Motion ◽  
Eye Position ◽  
Smooth Pursuit Eye Movements ◽  
Pontine Nucleus ◽  
Nucleus Reticularis Tegmenti Pontis ◽  
Pursuit Eye Movements ◽  
Nucleus Reticularis

1. Smooth pursuitlike eye movements were evoked with low current microstimulation delivered to rostral portions of the nucleus reticularis tegmenti pontis (rNRTP) in alert macaques. Microstimulation sites were selected by the observation of modulations in single-cell firing rates that were correlated with periodic smoothpursuit eye movements. Current intensities ranged from 10 to 120 microA and were routinely < 40 microA. Microstimulation was delivered either in the dark with no fixation, 100 ms after a fixation target was extinguished, or during maintained fixation of a stationary or moving target. Evoked eye movements also were studied under open-loop conditions with the target image stabilized on the retina. 2. Eye movements evoked in the absence of a target rapidly accelerated to a constant velocity that was maintained for the duration of the microstimulation. Evoked eye speeds ranged from 3.7 to 23 deg/s and averaged 11 deg/s. Evoked eye speed appeared to be linearly related to initial eye position with a sensitivity to initial eye position that averaged 0.23 deg.s-1.deg-1. While some horizontal and oblique smooth eye movements were elicited, microstimulation resulted in upward eye movements in 89% of the sites. 3. Evoked eye speed was found to be dependent on microstimulation pulse frequency and current intensity. Within limits, evoked eye speed increased with increases in stimulation frequency or current intensity. For stimulation frequencies < 300–400 Hz, only smooth pursuit-like eye movements were evoked. At higher stimulation frequencies, accompanying saccades consistently were elicited. 4. Feedback of retinal image motion interacted with the evoked eye movements to decrease eye speed if the visual motion was in the opposite direction as the evoked, pursuit-like eye movements. 5. The results implicate rNRTP as part of the neuronal substrate that controls smooth-pursuit eye movements. NRTP appears to be divided functionally into a rostral, pursuit-related portion and a caudal, saccade-related area. rNRTP is a component of a corticopontocerebellar circuit that presumably involves the pursuit area of the frontal eye field and that parallels the middle and medial superior temporal cerebral cortical/dorsalateral pontine nucleus (MT/MST-DLPN-cerebellum) pathway known to be involved also with regulating smooth-pursuit eye movements.

Target Selection by the Frontal Cortex during Coordinated Saccadic and Smooth Pursuit Eye Movements

2009 ◽  
Vol 21 (8) ◽  
pp. 1611-1627 ◽  
Author(s):  
Krishna Srihasam ◽  
Daniel Bullock ◽  
Stephen Grossberg
Keyword(s):  
Eye Movements ◽  
Smooth Pursuit ◽  
Current Model ◽  
Target Selection ◽  
Motion Processing ◽  
Parallel Model ◽  
Smooth Pursuit Eye Movements ◽  
Pontine Nucleus ◽  
Temporal Area ◽  
Pursuit Eye Movements

Oculomotor tracking of moving objects is an important component of visually based cognition and planning. Such tracking is achieved by a combination of saccades and smooth-pursuit eye movements. In particular, the saccadic and smooth-pursuit systems interact to often choose the same target, and to maximize its visibility through time. How do multiple brain regions interact, including frontal cortical areas, to decide the choice of a target among several competing moving stimuli? How is target selection information that is created by a bias (e.g., electrical stimulation) transferred from one movement system to another? These saccade–pursuit interactions are clarified by a new computational neural model, which describes interactions between motion processing areas: the middle temporal area, the middle superior temporal area, the frontal pursuit area, and the dorsal lateral pontine nucleus; saccade specification, selection, and planning areas: the lateral intraparietal area, the frontal eye fields, the substantia nigra pars reticulata, and the superior colliculus; the saccadic generator in the brain stem; and the cerebellum. Model simulations explain a broad range of neuroanatomical and neurophysiological data. These results are in contrast with the simplest parallel model with no interactions between saccades and pursuit other than common-target selection and recruitment of shared motoneurons. Actual tracking episodes in primates reveal multiple systematic deviations from predictions of the simplest parallel model, which are explained by the current model.

Response properties of dorsolateral pontine units during smooth pursuit in the rhesus macaque

1988 ◽  
Vol 60 (2) ◽  
pp. 664-686 ◽  
Author(s):  
M. J. Mustari ◽  
A. F. Fuchs ◽  
J. Wallman
Keyword(s):  
Eye Movements ◽  
Smooth Pursuit ◽  
Visual Sensitivity ◽  
Large Field ◽  
Motion Processing ◽  
Smooth Pursuit Eye Movements ◽  
Pontine Nucleus ◽  
Stimulus Velocity ◽  
Pursuit Eye Movements ◽  
Visual Motion Processing

1. The anatomical connections of the dorsolateral pontine nucleus (DLPN) implicate it in the production of smooth-pursuit eye movements. It receives inputs from cortical structures believed to be involved in visual motion processing (middle temporal cortex) or motion execution (posterior parietal cortex) and projects to the flocculus of the cerebellum, which is involved in smooth pursuit. To determine the role of the DLPN in smooth pursuit, we have studied the discharge patterns of 191 DLPN neurons in five monkeys trained to make smooth-pursuit eye movements of a spot moving either across a patterned background or in darkness. 2. Four unit types could be distinguished. Visual units (15%) discharged in response to movement of a large textured pattern, often in a direction-selective fashion but not during smooth pursuit of a spot in the dark. Eye movement neurons (31%) discharged during sinusoidal smooth pursuit in the dark with peak discharge rate either at peak eye position or peak eye velocity, but they showed no response during background movement or during other visual stimulation. These units continued to discharge when the target was extinguished (blanked) briefly, and the monkey continued to make smooth eye movements in the dark. The majority (54%) of our DLPN units discharged during both smooth pursuit in the dark and background movement while the monkey fixated. Blanking the target during smooth pursuit revealed that these units fell into two distinct classes. Visual pursuit units ceased discharging during a blank, suggesting that they had only a visual sensitivity. Pursuit and visual units continued to discharge during the blank, indicating that they had a combined oculomotor and visual sensitivity. 3. Ninety-five percent of the units that discharged during smooth pursuit were direction selective. These units had rather broad directional tuning curves with widths at half height ranging from 65 to 180 degrees. Many preferred directions for DLPN units were observed, although the vertical and near-vertical directions predominated. 4. Most units that responded to large-field background movement were direction selective. During sinusoidal movement of a large-field background, half of them also discharged in relation to stimulus velocity, whereas others did not.

scholarly journals The Impact of Neonatal Morbidities on Smooth Pursuit Eye Movements in Very Preterm Infants

2011 ◽  
Vol 70 ◽  
pp. 352-352 ◽  
Author(s):  
K Strand Brodd ◽  
K Rosander ◽  
H Grönqvist ◽  
G Holmström ◽  
B Strömberg ◽  
...  
Keyword(s):  
Eye Movements ◽  
Preterm Infants ◽  
Smooth Pursuit ◽  
Smooth Pursuit Eye Movements ◽  
Very Preterm Infants ◽  
Very Preterm ◽  
Pursuit Eye Movements ◽  
The Impact
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