Saccadic Eye Movements and Visual Stability: Preliminary Considerations Towards a Cognitive Approach

The question of how the brain can construct a stable representation of the external world despite eye movements is a very old one. If there have been some wrong statements of problems (such as the inverted retinal image), other statements are less naive and have led to analytic solutions possibly adopted by the brain to counteract the spurious effects of eye movements. Following the MacKay (1973) objections to the analytic view of perceptual stability, Bridgeman et al. claim that the idea that signals canceling the effects of saccadic eye movements are needed is also a misconception, as is the claim that stability and position encoding are two distinct problems. It must be remembered, however, that what made the theory of “cancellation” formulated by von Holst and Mittelstaedt (1950) so appealing was the clinical observation of perceptual instability following ocular paralysis. Following the concept of corollary discharge, the theory of efference copy had the advantage of simultaneously solving three problems: the stability of the visual world during the saccade, the same visual stability across saccades, and the visual constancy problem of allowing the subject to know where an object in space is.

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Previewing a face in the periphery reduces the fN170: Combined EEG and eye-tracking suggests two stages of trans-saccadic predictive processes

10.1101/468900 ◽

2018 ◽

Cited By ~ 1

Author(s):

Christoph Huber-Huber ◽

Antimo Buonocore ◽

Clayton Hickey ◽

David Melcher

Keyword(s):

Eye Movements ◽

Eye Tracking ◽

Bayes Factor ◽

Discrimination Performance ◽

Saccadic Eye Movements ◽

Visual Stability ◽

Face Inversion Effect ◽

Face Stimuli ◽

Two Stages ◽

Predictive Processes

AbstractThe world appears stable despite saccadic eye-movements. One possible explanation for this phenomenon is that the visual system predicts upcoming input across saccadic eye-movements, based on peripheral preview of the saccadic target. We tested this idea using concurrent electroencephalography (EEG) and eye-tracking. Participants made cued saccades to peripheral upright or inverted face stimuli that could change (invalid preview) or keep their orientation (valid preview) across the saccade. Experiment 1 demonstrated better discrimination performance and a reduced fixation-locked N170 (fN170) with valid than with invalid preview demonstrating integration of pre- and post-saccadic information. Moreover, the early fixation-locked EEG showed a preview face inversion effect suggesting that we perceive pre-saccadic input up to about 170 ms post fixation-onset, at least for face orientation. Experiment 2 replicated Experiment 1 and manipulated the proportion of valid and invalid trials (mostly valid versus mostly invalid, 66.6% to 33.3%) to test whether the preview effect reflected active expectations. A whole-scalp Bayes factor analysis provided evidence for no influence of proportion on the fN170 preview effect. Instead, before the saccade the preview face orientation effect declined earlier in the mostly invalid than in the mostly valid block suggesting some form of pre-saccadic expectations. We conclude that visual stability is achieved by two trans-saccadic integration processes: pre-saccadic prediction, reflected in the pre-saccadic proportion modulation, and early post-saccadic change-detection reflected in the fN170 preview effect.

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A theory of visual stability across saccadic eye movements

Behavioral and Brain Sciences ◽

10.1017/s0140525x00034361 ◽

1994 ◽

Vol 17 (2) ◽

pp. 247-258 ◽

Cited By ~ 156

Author(s):

Bruce Bridgeman ◽

A. H. C. Van der Heijden ◽

Boris M. Velichkovsky

Keyword(s):

Eye Movements ◽

Saccadic Eye Movements ◽

Visual Direction ◽

Visual Stability ◽

Perceptual Stability ◽

Adequate Information ◽

Psychological Evidence ◽

Calibration Solution ◽

Final Question ◽

Direction Constancy

AbstractWe identify two aspects of the problem of maintaining perceptual stability despite an observer's eye movements. The first, visual direction constancy, is the (egocentric) stability of apparent positions of objects in the visual world relative to the perceiver. The second, visual position constancy, is the (exocentric) stability of positions of objects relative to each other. We analyze the constancy of visual direction despite saccadic eye movements.Three information sources have been proposed to enable the visual system to achieve stability: the structure of the visual field, proprioceptive inflow, and a copy of neural efference or outflow to the extraocular muscles. None of these sources by itself provides adequate information to achieve visual direction constancy; present evidence indicates that all three are used.Our final question concerns how information processing operations result in a stable world. The three traditionally suggested means have been elimination, translation, or evaluation. All are rejected. From a review of the physiological and psychological evidence we conclude that no subtraction, compensation, or evaluation need take place. The problem for which these solutions were developed turns out to be a false one. We propose a “calibration” solution: correct spatiotopic positions are calculated anew for each fixation. Inflow, outflow, and retinal sources are used in this calculation: saccadic suppression of displacement bridges the errors between these sources and the actual extent of movement.

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Saccadic eye movements and visual stability

Nature ◽

10.1038/275766a0 ◽

1978 ◽

Vol 275 (5682) ◽

pp. 766-768 ◽

Cited By ~ 9

Author(s):

P. LENNIE ◽

A. SIDWELL

Keyword(s):

Eye Movements ◽

Saccadic Eye Movements ◽

Visual Stability

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A Retinotopic Attentional Trace after Saccadic Eye Movements: Evidence from Event-related Potentials

Journal of Cognitive Neuroscience ◽

10.1162/jocn_a_00390 ◽

2013 ◽

Vol 25 (9) ◽

pp. 1563-1577 ◽

Cited By ~ 11

Author(s):

Durk Talsma ◽

Brian J. White ◽

Sebastiaan Mathôt ◽

Douglas P. Munoz ◽

Jan Theeuwes

Keyword(s):

Eye Movements ◽

Eye Movement ◽

Visual Stimulus ◽

Saccadic Eye Movements ◽

Event Related Potentials ◽

Saccadic Eye Movement ◽

Visual Stability ◽

Specific Location ◽

Related Potentials ◽

Significant Attenuation

Saccadic eye movements are a major source of disruption to visual stability, yet we experience little of this disruption. We can keep track of the same object across multiple saccades. It is generally assumed that visual stability is due to the process of remapping, in which retinotopically organized maps are updated to compensate for the retinal shifts caused by eye movements. Recent behavioral and ERP evidence suggests that visual attention is also remapped, but that it may still leave a residual retinotopic trace immediately after a saccade. The current study was designed to further examine electrophysiological evidence for such a retinotopic trace by recording ERPs elicited by stimuli that were presented immediately after a saccade (80 msec SOA). Participants were required to maintain attention at a specific location (and to memorize this location) while making a saccadic eye movement. Immediately after the saccade, a visual stimulus was briefly presented at either the attended location (the same spatiotopic location), a location that matched the attended location retinotopically (the same retinotopic location), or one of two control locations. ERP data revealed an enhanced P1 amplitude for the stimulus presented at the retinotopically matched location, but a significant attenuation for probes presented at the original attended location. These results are consistent with the hypothesis that visuospatial attention lingers in retinotopic coordinates immediately following gaze shifts.

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