Predicting eye movements of rhesus monkeys searching for pedestrians in natural images

In free-viewing experiments, primates orient preferentially toward faces and face-like stimuli. To investigate the neural basis of this behavior, we measured the spontaneous viewing preferences of monkeys with selective bilateral amygdala lesions. The results revealed that when faces and nonface objects were presented simultaneously, monkeys with amygdala lesions had no viewing preference for either conspecific faces or illusory facial features in everyday objects. Instead of directing eye movements toward socially relevant features in natural images, we found that, after amygdala loss, monkeys are biased toward features with increased low-level salience. We conclude that the amygdala has a role in our earliest specialized response to faces, a behavior thought to be a precursor for efficient social communication and essential for the development of face-selective cortex.

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Effects of cerebellar lesions on saccadic eye movements

Journal of Neurophysiology ◽

10.1152/jn.1976.39.6.1246 ◽

1976 ◽

Vol 39 (6) ◽

pp. 1246-1256 ◽

Cited By ~ 154

Author(s):

L. Ritchie

Keyword(s):

Eye Movements ◽

Macaca Mulatta ◽

Rhesus Monkeys ◽

Saccadic Eye Movements ◽

Motor Systems ◽

Antagonist Muscle ◽

Restoring Forces ◽

System 2 ◽

Cerebellar Lesions ◽

Cerebellar Symptoms

1. Areas of cerebellar cortex related to saccadic eye movements were ablated in three Macaca mulatta monkeys trained to fixate visual targets. There followed a postoperative dysmetria of saccadic eye movements which appeared to be the result of an impairment specifically within the saccadic system. 2. Convergent evidence from two experimental paradigms indicated that the saccadic deficit was a function of the position of the eye in the orbit and did not involve retinal error processing. 3. The pattern of this position-dependent dysmetria suggests that the eye was no longer fully compensating for the elastic restoring forces imposed by the orbital medium and antagonist muscle(s). 4. The similarity of these data to saccadic eye movements of human cerebellar patients and arm movements of rhesus monkeys with cerebellar lesions indicates that the inability to compensate for the differential loads placed on motor systems by the mechanics of those systems may explain several cerebellar symptoms.

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Image Structure at the Center of Gaze during Free Viewing

Journal of Cognitive Neuroscience ◽

10.1162/jocn.2006.18.5.737 ◽

2006 ◽

Vol 18 (5) ◽

pp. 737-748 ◽

Cited By ~ 14

Author(s):

Valentin Dragoi ◽

Mriganka Sur

Keyword(s):

Eye Movements ◽

Rhesus Monkeys ◽

Discrimination Performance ◽

Natural Scenes ◽

Image Patch ◽

Image Scanning ◽

Retinal Stimulation ◽

Free Viewing ◽

Precise Knowledge ◽

Orientation Structure

It is generally believed that the visual system is adapted to the statistics of the visual world. Measuring and understanding these statistics require precise knowledge of the structure of the signals reaching fovea during image scanning. However, despite the fact that eye movements cause retinal stimulation to change several times in a second, it is implicitly assumed that images are sampled uniformly during natural viewing. By analyzing the eye movements of three rhesus monkeys freely viewing natural scenes, we report here significant anisotropy in stimulus statistics at the center of gaze. We find that fixation on an image patch is more likely to be followed by a saccade to a nearby patch of similar orientation structure or by a saccade to a more distant patch of largely dissimilar orientation structure. Furthermore, we show that orientation-selective neurons in the primary visual cortex (V1) can take advantage of eye movement statistics to selectively improve their discrimination performance.

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Audio-visual integration during overt visual attention

Journal of Eye Movement Research ◽

10.16910/jemr.1.2.4 ◽

2008 ◽

Vol 1 (2) ◽

Author(s):

Cliodhna Quigley ◽

Selim Onat ◽

Sue Harding ◽

Martin Cooke ◽

Peter König

Keyword(s):

Regression Analysis ◽

Eye Movements ◽

Natural Images ◽

Spatial Bias ◽

Sources Of Information ◽

Integration Process ◽

Image Region ◽

Visual Integration ◽

Operational Conditions ◽

Different Sources

How do different sources of information arising from different modalities interact to control where we look? To answer this question with respect to real-world operational conditions we presented natural images and spatially localized sounds in (V)isual, Audio-visual (AV) and (A)uditory conditions and measured subjects' eye-movements. Our results demonstrate that eye-movements in AV conditions are spatially biased towards the part of the image corresponding to the sound source. Interestingly, this spatial bias is dependent on the probability of a given image region to be fixated (saliency) in the V condition. This indicates that fixation behaviour during the AV conditions is the result of an integration process. Regression analysis shows that this integration is best accounted for by a linear combination of unimodal saliencies.

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Accuracy of Saccades to Remembered Targets as a Function of Body Orientation in Space

Journal of Neurophysiology ◽

10.1152/jn.00141.2003 ◽

2003 ◽

Vol 90 (1) ◽

pp. 521-524 ◽

Cited By ~ 2

Author(s):

Joshua T. Vogelstein ◽

Lawrence H. Snyder ◽

Dora E. Angelaki

Keyword(s):

Eye Movements ◽

Rhesus Monkeys ◽

Saccadic Eye Movements ◽

Body Axis ◽

Body Orientation ◽

Upright Orientation ◽

The Asymmetry

A vertical asymmetry in memory-guided saccadic eye movements has been previously demonstrated in humans and in rhesus monkeys. In the upright orientation, saccades generally land several degrees above the target. The origin of this asymmetry has remained unknown. In this study, we investigated whether the asymmetry in memory saccades is dependent on body orientation in space. Thus animals performed memory saccades in four different body orientations: upright, left-side-down (LSD), right-side-down (RSD), and supine. Data in all three rhesus monkeys confirm previous observations regarding a significant upward vertical asymmetry. Saccade errors made from LSD and RSD postures were partitioned into components made along the axis of gravity and along the vertical body axis. Up/down asymmetry persisted only in body coordinates but not in gravity coordinates. However, this asymmetry was generally reduced in tilted positions. Therefore the upward bias seen in memory saccades is egocentric although orientation in space might play a modulatory role.

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Primate Translational Vestibuloocular Reflexes. II. Version and Vergence Responses to Fore-Aft Motion

Journal of Neurophysiology ◽

10.1152/jn.2000.83.3.1648 ◽

2000 ◽

Vol 83 (3) ◽

pp. 1648-1661 ◽

Cited By ~ 31

Author(s):

M. Quinn McHenry ◽

Dora E. Angelaki

Keyword(s):

Eye Movements ◽

Rhesus Monkeys ◽

Viewing Distance ◽

Functional Dependencies ◽

Ideal Behavior ◽

Pass Filter ◽

Disjunctive Eye Movements ◽

Eye Velocity ◽

High Pass ◽

Straight Ahead

To maintain binocular fixation on near targets during fore-aft translational disturbances, largely disjunctive eye movements are elicited the amplitude and direction of which should be tuned to the horizontal and vertical eccentricities of the target. The eye movements generated during this task have been investigated here as trained rhesus monkeys fixated isovergence targets at different horizontal and vertical eccentricities during 10 Hz fore-aft oscillations. The elicited eye movements complied with the geometric requirements for binocular fixation, although not ideally. First, the corresponding vergence angle for which the movement of each eye would be compensatory was consistently less than that dictated by the actual fixation parameters. Second, the eye position with zero sensitivity to translation was not straight ahead, as geometrically required, but rather exhibited a systematic dependence on viewing distance and vergence angle. Third, responses were asymmetric, with gains being larger for abducting and downward compared with adducting and upward gaze directions, respectively. As frequency was varied between 4 and 12 Hz, responses exhibited high-pass filter properties with significant differences between abduction and adduction responses. As a result of these differences, vergence sensitivity increased as a function of frequency with a steeper slope than that of version. Despite largely undercompensatory version responses, vergence sensitivity was closer to ideal. Moreover, the observed dependence of vergence sensitivity on vergence angle, which was varied between 2.5 and 10 MA, was largely linear rather than quadratic (as geometrically predicted). We conclude that the spatial tuning of eye velocity sensitivity as a function of gaze and viewing distance follows the general geometric dependencies required for the maintenance of foveal visual acuity. However, systematic deviations from ideal behavior exist that might reflect asymmetric processing of abduction/adduction responses perhaps because of different functional dependencies of version and vergence eye movement components during translation.

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Three-Dimensional Eye Movements Evoked by Electrical Micro-Stimulation of the Trochlear Nerve in Alert Rhesus Monkeys

Three-Dimensional Kinematics of Eye, Head and Limb Movements ◽

10.1201/9780203735701-15 ◽

2020 ◽

pp. 133-138

Author(s):

Y. Suzuki ◽

D. Straumann ◽

K. Hepp ◽

V. Henn

Keyword(s):

Eye Movements ◽

Rhesus Monkeys ◽

Three Dimensional ◽

Trochlear Nerve ◽

Stimulation Of

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Short-Latency Primate Vestibuloocular Responses During Translation

Journal of Neurophysiology ◽

10.1152/jn.1999.82.3.1651 ◽

1999 ◽

Vol 82 (3) ◽

pp. 1651-1654 ◽

Cited By ~ 47

Author(s):

Dora E. Angelaki ◽

M. Quinn McHenry

Keyword(s):

Eye Movements ◽

Rhesus Monkeys ◽

Early Response ◽

Short Latency ◽

Viewing Distance ◽

Movement Response ◽

Response Latencies ◽

Dependent Behavior ◽

Response Profile ◽

Initial Acceleration

Short-lasting, transient head displacements and near target fixation were used to measure the latency and early response gain of vestibularly evoked eye movements during lateral and fore-aft translations in rhesus monkeys. The latency of the horizontal eye movements elicited during lateral motion was 11.9 ± 5.4 ms. Viewing distance-dependent behavior was seen as early as the beginning of the response profile. For fore-aft motion, latencies were different for forward and backward displacements. Latency averaged 7.1 ± 9.3 ms during forward motion (same for both eyes) and 12.5 ± 6.3 ms for the adducting eye (e.g., left eye during right fixation) during backward motion. Latencies during backward motion were significantly longer for the abducting eye (18.9 ± 9.8 ms). Initial acceleration gains of the two eyes were generally larger than unity but asymmetric. Specifically, gains were consistently larger for abducting than adducting eye movements. The large initial acceleration gains tended to compensate for the response latencies such that the early eye movement response approached, albeit consistently incompletely, that required for maintaining visual acuity during the movement. These short-latency vestibuloocular responses could complement the visually generated optic flow responses that have been shown to exhibit much longer latencies.

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The kinematics of far-near re-fixation saccades

Journal of Neurophysiology ◽

10.1152/jn.00957.2014 ◽

2015 ◽

Vol 113 (9) ◽

pp. 3197-3208 ◽

Cited By ~ 3

Author(s):

Bernhard J. M. Hess ◽

H. Misslisch

Keyword(s):

Eye Movements ◽

Rhesus Monkeys ◽

Horizontal Plane ◽

Three Dimensional ◽

Vertical Direction ◽

Opposite Polarity ◽

Target Acquisition ◽

Ocular Torsion ◽

Frontoparallel Plane ◽

Rapid Eye Movements

We have analyzed the three-dimensional spatiotemporal characteristics of saccadic refixations between far and near targets in three behaviorally trained rhesus monkeys. The kinematics underlying these rapid eye movements can be accurately described by rotations of the eyes in four different planes, namely, first disconjugate rotations in the horizontal plane of regard converging the eyes toward the near target, followed by rotations in each eye's vertical direction plane, and finally, disconjugate rotations in a common frontoparallel plane. This compounded rotation of the eye was underlying an initially fast-rising variable torsion that typically overshot the final torsion, which the eyes attained at the time of target acquisition. The torsion consisted of a coarse, widely varying component of opposite polarity in the two eyes, which contained a more robust, much smaller modulation that sharply increased toward the end of saccades. The reorientation of the eyes in torsion depended on each eye's azimuth, elevation, and target distance. We conclude that refixation saccades are generated by motor commands that control ocular torsion in concert with the saccade generator, which operates in Donders-Listing kinematics underlying Listing's law.

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The influence of objecthood on the representation of natural images in the visual cortex

10.1101/2021.09.21.461209 ◽

2021 ◽

Author(s):

Paolo Papale ◽

Wietske Zuiderbaan ◽

Rob R.M. Teeuwen ◽

Amparo Gilhuis ◽

Matthew W. Self ◽

...

Keyword(s):

Visual Cortex ◽

Eye Movements ◽

Neuronal Activity ◽

Cortical Neurons ◽

Neuronal Response ◽

Late Phase ◽

Object Perception ◽

Natural Images ◽

Early Visual Cortex ◽

Visual Cortical

Neurons in early visual cortex are not only sensitive to the image elements in their receptive field but also to the context determining whether the elements are part of an object or background. We here assessed the effect of objecthood in natural images on neuronal activity in early visual cortex, with fMRI in humans and electrophysiology in monkeys. We report that boundaries and interiors of objects elicit more activity than the background. Boundary effects occur remarkably early, implying that visual cortical neurons are tuned to features characterizing object boundaries in natural images. When a new image is presented the influence of the object interiors on neuronal activity occurs during a late phase of neuronal response and earlier when eye movements shift the image representation, implying that object representations are remapped across eye-movements. Our results reveal how object perception shapes the representation of natural images in early visual cortex.

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