Eye-movement patterns for perceiving bistable figures.

BackgroundThe anti-saccade task, when people must respond in the direction opposite to a visual stimulus, has been used as a marker of operation of the frontal cortical oculomotor area. However, early development of oculomotor control has been little studied with the infant anti-saccade paradigm, and a few studies did not recognize anti-saccades in infants in light of the results of adult anti-saccade. Since the characteristics of infant eye movements are little known, applying the criteria used in adult study is by no means the best way to study infant anti-saccade. As it is indicated that coordinated eye and head movements often enable infants to control the direction of their gaze, head movements should be examined as an infant orienting response. The aim of this study was to address how infants used eye and head movements during the anti-saccade paradigm. To distinguish infants' responses, we also investigated eye and head movements during a task for an inhibition of return. Inhibition of return, in which delayed responses occur in the direction to which attention had previously been oriented, has been thought to mark activity of the superior colliculus. Since the superior colliculus is thought to develop much earlier in life than the frontal lobes, we thought it useful to compare these task performances during infancy.MethodsInfants were divided into three groups according to age. Anti-saccade and inhibition-of-return tasks were given. Their eye and head movements during tasks were independently recorded by the corneal reflection method in the head-free condition.ResultsYounger infants tended to initiate eye movement less than older ones in both tasks. In the anti-saccade task, responses opposite to the cue tended to show longer latency than responses to the cue. Infants made faster responses toward the side opposite the cue when it was to the right than when it was left of fixation. Regarding the comparison of responses toward the side opposite the cue between two tasks, the leftward eye movement was faster than the leftward head movements in the inhibition-of-return task, while no difference of latency was observed between eye and head movements in the anti-saccade task. A qualitative analysis of the trajectory of these responses revealed that head movement trajectories were steeper in the anti-saccade than in the inhibition-of-return task.ConclusionYounger infants move head and eyes together, with head movements frequently starting first. On the other hand, both the leftward latency difference between eye and head and gentle trajectories of head in inhibition of return indicate that eye movements are more predominant over head movements in the inhibition-of-return task than in the anti-saccade task. This would suggest an earlier developing inhibition-of-return mechanism.

On the role of eye movement monitoring and discouragement on inhibition of return in a go/no-go task

Peripheral cues induce facilitation with short cue-target intervals and inhibition of return (IOR) with long cue-target intervals. Modulations of facilitation and IOR by continuous displacements of the eye or the cued stimuli are poorly understood. Previously, the retinal coordinates of the cued location were changed by saccadic or smooth pursuit eye movements during the cue-target interval. In contrast, we probed the relevant coordinates for facilitation and IOR by orthogonally varying object motion (stationary, moving) and eye movement (fixation, smooth pursuit). In the pursuit conditions, cue and target were presented during the ongoing eye movement and observers made a saccade to the target. Importantly, we found facilitation and IOR of similar size during smooth pursuit and fixation. The results suggest that involuntary orienting is possible even when attention has to be allocated to the moving target during smooth pursuit. Comparison of conditions with stabilized and moving objects suggest an oculocentric basis for facilitation as well as inhibition. Facilitation and IOR were reduced with objects that moved on the retina both with smooth pursuit and eye fixation.

Responses are slower to targets appearing in recently inspected locations, an effect known as Inhibition of Return (IOR). IOR is typically viewed as the consequence of an involuntary mechanism that prevents reinspection of previously visited locations and thereby biases attention toward novel locations during visual search. For an inhibitory tagging mechanism to serve this function effectively, it should be robust against eye movements and the movements of objects in the environment. We investigated whether the predictability of motion supports the coding of inhibitory tags in spatiotopic coordinates across eye movements and object-based coordinates across object motion. IOR was observed in both retinotopic and spatiotopic coordinates across eye movements, regardless of the predictability of the eye movement direction. In a matching experiment, but with predictable or unpredictable object motion instead of eye movements, IOR was reduced in magnitude by object motion and was not observed in object-based coordinates, even when the motion was predictable. Together the results suggest inhibitory tags can track objects as they move across the retina, but only when this motion is self-generated. We conclude that efference copy, not prediction, plays a key role in maintaining inhibition on previously attended objects across saccades.

In two experiments we investigated whether bistable visual perception is influenced by passive own body displacements due to vestibular stimulation. For this we passively rotated our participants around the vertical (yaw) axis while observing different rotating bistable stimuli (bodily or non-bodily) with different ambiguous motion directions. Based on previous work on multimodal effects on bistable perception, we hypothesized that vestibular stimulation should alter bistable perception and that the effects should differ for bodily versus non-bodily stimuli. In the first experiment, it was found that the rotation bias (i.e., the difference between the percentage of time that a CW or CCW rotation was perceived) was selectively modulated by vestibular stimulation: the perceived duration of the bodily stimuli was longer for the rotation direction congruent with the subject's own body rotation, whereas the opposite was true for the non-bodily stimulus (Necker cube). The results found in the second experiment extend the findings from the first experiment and show that these vestibular effects on bistable perception only occur when the axis of rotation of the bodily stimulus matches the axis of passive own body rotation. These findings indicate that the effect of vestibular stimulation on the rotation bias depends on the stimulus that is presented and the rotation axis of the stimulus. Although most studies on vestibular processing have traditionally focused on multisensory signal integration for posture, balance, and heading direction, the present data show that vestibular self-motion influences the perception of bistable bodily stimuli revealing the importance of vestibular mechanisms for visual consciousness.

Preliminary fMRI research has suggested that both bistable figure reversal and Symbol Search (a measure of processing speed) utilize the same neural pathways during task execution, namely the dorsolateral prefrontal cortex. The fMRI findings predict a positive relationship between Symbol Search (SS) and bistable figure reversal (BFR). In Study 1, a bistable Necker Cube and the My Wife/My Mother-in-law figure were presented on cards, and participants indicated reversals by tapping on a table. The frequency of perceptual reversals was positively correlated with performance on SS (WAIS-III) but not with Picture Completion scores (a measure of visual processing). In Study 2 the Necker Cube was presented on a computer screen, and eye movements were monitored. Participants indicated reversals by pressing a response button. Again, the frequency of perceptual reversals of the Necker Cube was positively correlated with performance on SS (WAIS-IV, this time). No correlation was found with looking strategy, as indexed by eye movement variables. The present study provides incremental validity for interpreting and highlighting SS as a measure of attention and working memory.

Although inhibition of return (IOR) has been examined in a number of experimental circumstances, it is not known if the number of potential target locations affects the magnitude of the inhibition at a cued location. To investigate this issue, participants were randomly presented with displays of two, four, or six potential target locations in a typical IOR detection task. The findings indicated that number of target locations did not affect IOR and that RTs at uncued locations varied systematically as a function of the spatial relationship between the cued and uncued location. Resume Bien que l'inhibition du retour (IOR) ait ete etudiee dans differents contextes experimentaux, on ne sait pas si le nombre d'emplacements possibles des cibles a un effet sur l'importance de l'inhibition a un emplacement marque par un indice. Pour approfondir l'examen de la question, on a presente aux participants des series de 2, 4 ou 6 emplacements possibles de cibles dans le contexte d'une tache typique de detection IOR. Les resultats indiquent que le nombre d'emplacements des cibles n'influe pas sur l'inhibition du retour et que le temps de reponse, pour les emplacements sans indice, varie systematiquement en fonction de la relation spatiale entre les emplacements accompagnes et non accompagnes d'indices. A considerable amount of research has examined inhibition of return (IOR) since the discovery of the phenomenon by Posner and Cohen in 1984. Posner and Cohen found that targets were detected more slowly at locations that had previously been cued when the delay between the presentation of the cue and the target exceeded 300 ms. They coined the term IOR for the effect, referring to their original notion that attention was inhibited to return to previously attended locations. Presumably, this inhibition occurred to make visual or attentional searches more efficient by biasing attention toward novel locations and away from previously inspected locations. It is because of this implication that IOR has been a topic for researchers in visual attention for more than a decade. Despite the wealth of research that has been conducted on IOR, some basic questions regarding the inhibitory effect have remained unasked and, consequently, unanswered. One of these questions is: Does the number of potential target locations affect IOR? This is a pertinent question because studies that have examined IOR have used anywhere from two (e.g., Maylor, 1984) to eight (e.g., Wright & Richard, 1996) potential target locations. Without knowing whether the number of potential target locations does or does not affect IOR, it is difficult to examine and interpret the different inhibitory effects produced between various experimental conditions. In addition to the pragmatic reasons for examining the effect of various possible target locations on IOR, there are also theoretical reasons to suggest that the number of locations may, or may not, differently affect IOR. On the one hand, if IOR does reflect the output of an attentional mechanism that improves searches, one might expect that the number of locations where the target might potentially occur would have a negative influence on the magnitude of IOR. Assuming that some amount of attention is allocated to each target location placeholder in a display, larger number of placeholders should require a greater proportion of the available attentional resources. This leads to a situation in which the amount of inhibition might be expected to decrease with increasing numbers of potential target locations because it would become more difficult to keep track of novel and previously attended locations. On the other hand, it may be that previously attended locations are tagged with inhibitory tags that require relatively little cognitive overhead, making the number of potential target locations largely irrelevant. For example, Klein and Taylor (1994) suggested that IOR occurs when eye movements are planned, but not executed, toward a specific location. …

A number of psychophysical methods that suppress retinal input from reaching awareness have been used to isolate and study the neural correlates of visual consciousness. I describe a novel disappearance phenomenon in which a low-contrast peripheral pattern is vividly erased from awareness: after adapting to the pattern for a few seconds, flashing a high-contrast patch over it can elicit the perceptual disappearance of the stimulus. This finding was explained in terms of nonlinear interaction between adaptation to sustained spatial pattern and rapid gain adjustment to transient change. It was next shown that transient changes contingent upon prior adaptation elicit perceptual alternations in structure from motion, binocular rivalry, Necker cube, and ambiguous apparent motion—linking disappearance phenomena and bistable perception. We next used binocular rivalry and inattentional blindness to examine if invisible inputs influence the neuronal mechanisms that adapt to different aspects of the stimuli. The face identity-specific aftereffect was found to be cancelled by binocular suppression or by inattentional blindness of the inducing face. Conversely, the same suppression did not interfere with the orientation-specific aftereffect. Thus, the competition between incompatible or interfering visual inputs to reach awareness is resolved before those aspects of information that are exploited in face identification are processed. Subsequent experiments showed that face identity aftereffect is invariant to eye movements, but fMRI adaptation in face-selective region of the fusiform cortex did not show such invariance. Therefore identity aftereffect originates either at the same level or subsequent to the level of face processing in the fusiform area. Next, we show that recognition of facial emotional expressions occurs after the level of attentional selection: visual search results were incompatible with preattentive processing of emotional categories. We thus suggest that the invisible or unattended faces are suppressed in early visual areas. This conjecture was experimentally confirmed by showing that when a stimulus is not attended, it evoked a weaker and weaker response in fMRI in subsequent stages of visual processing hierarchy. Thus, attention determines how far the visual input is processed and whether or not a high-level representation of the input would be constructed.

Inhibition of return (IOR) is the effect of slower responses to validly than invalidly cued targets. The discovery of IOR raised controversy as to whether it has two “flavors”, i.e., attentional/perceptual and motoric, or whether it is a homogeneous visual-motor phenomenon that should be understood in terms of the preparation of different effectors (mainly eye movement). Since manipulation of fixation offset (0 and 200 ms gap) is believed to affect the latency of saccades, we measured its influence on saccadic and manual IOR with a simple keypress response when eye movements were forbidden. In the two experiments which we carried out, the fixation offset decreased IOR in both the saccadic and the manual conditions. The results suggest the limitations of the attentional hypothesis, which assumes that manual IOR is independent of the motoric component; they are also in line with the tenets of the oculomotor hypothesis of IOR.

Response time can be delayed if a target stimulus appears at a location or object that was previously cued. This inhibition of return (IOR) phenomenon has been attributed to a delay in activating attentional or motor processes to a previously cued stimulus. Two experiments required subjects to localize or identify a target stimulus. In Experiment 1, the subjects' eyes were not monitored. In Experiment 2, the subjects' eyes were monitored, and the subjects were instructed to either execute or withhold an eye movement to a target stimulus. The results indicated that IOR was always present for location and identification responses, supporting an attentional account of IOR. However, IOR was larger when eye movements were executed, indicating that a motor component can contribute to IOR. Finally, when eye movements were withheld, IOR was larger when a target was presented alone than when it was presented with a distractor, suggesting that IOR is larger for exogenous than for endogenous covert orienting. Together, the data indicate that IOR is composed of both an oculomotor component and an attentional component.

A predator leaps out from behind a rock—that's sure to catch your attention. The idea that certain types of stimuli have a hardwired “hotline” to attention has fascinated psychologists, philosophers, and neuroscientists for more than a century. In 1890, William James enumerated “strange

Taylor and Klein (Journal of Experimental Psychology: Human Perception and Performance 26:1639-1656, 2000) discovered two mutually exclusive "flavors" of inhibition of return (IOR): When the oculomotor system is "actively suppressed," IOR affects input processes (the perception/attention flavor), whereas when the oculomotor system is "engaged," IOR affects output processes (the motor flavor). Studies of brain activity with ignored cues have typically reported that IOR reduces an early sensory event-related potential (ERP) component (i.e., the P1 component) of the brain's response to the target. Since eye movements were discouraged in these experiments, the P1 reduction might be a reflection of the perception/attention flavor of IOR. If, instead of ignoring the cue, participants made a prosaccade to the cue (and then returned to fixation) before responding to the target, the motor flavor of IOR should then be generated. We compared these two conditions while monitoring eye position and recording ERPs to the targets. If the P1 modulation is related to the perceptual/attentional flavor of IOR, we hypothesized that it might be absent when the motoric flavor of IOR was generated by a prosaccade to the cue. Our results demonstrated that target-related P1 reductions and behavioral IOR were similar, and significant, in both conditions. However, P1 modulations were significantly correlated with behavioral IOR only when the oculomotor system was actively suppressed, suggesting that P1 modulations may only affect behaviorally exhibited IOR when the attentional/perceptual flavor of IOR is recruited.

Attention can be covertly shifted to peripheral stimuli to improve their processing. However, attention is also then inhibited against returning to the previously attended location; thus, both detection and discrimination of a stimulus presented at that location decrease (the inhibition of return [IOR] effect). The after-effect of the covert orienting hypothesis postulates a close link between attention shifting, IOR, and oculomotor control. The fixation offset, which improves the generation of saccades, decreases IOR in detection tasks, suggesting a close link between IOR and oculomotor control. However, according to some alternative views (e.g., the input-based IOR hypothesis and the object files segregation/integration hypothesis), IOR may be related to some sensory rather than motor processes. Some studies support that view and show that IOR may occur differently in detection and discrimination tasks and that oculomotor processes do not affect IOR in tasks where manual responses are required and eye movements are suppressed. Two experiments presented in this article show that removing the fixation point decreases manual IOR in detection and discrimination tasks. The results are discussed in terms of various theoretical approaches.

Decades of research using Posner's classic spatial cueing paradigm has uncovered at least two forms of inhibition of return (IOR) in the aftermath of an exogenous, peripheral orienting cue. One prominent dissociation concerns the role of covert and overt orienting in generating IOR effects that relate to perception- and action-oriented processes, respectively. Another prominent dissociation concerns the role of covert and overt orienting in generating IOR effects that depend on object- and space-based representation, respectively. Our objective was to evaluate whether these dichotomies are functionally equivalent by manipulating placeholder object presence in the cueing paradigm. By discouraging eye movements throughout, Experiments 1A and 1B validated a perception-oriented form of IOR that depended critically on placeholders. Experiment 2A demonstrated that IOR was robust without placeholders when eye movements went to the cue and back to fixation before the manual response target. In Experiment 2B, we replicated Experiment 2A's procedures except we discouraged eye movements. IOR was observed, albeit only weakly and significantly diminished relative to when eye movements were involved. We conclude that action-oriented IOR is robust against placeholders but that the magnitude of perception-oriented IOR is critically sensitive to placeholder presence when unwanted oculomotor activity can be ruled out.

Event Abstract Back to Event Dissociating the neural mechanisms underlying spatiotopic and retinotopic inhibition of return: An investigation using eye tracking and electroencephalography Jason Satel1*, Matthew D. Hilchey2, Zhiguo Wang3 and Raymond M. Klein2 1 University of Nottingham Malaysia Campus, School of Psychology, Malaysia 2 Dalhousie University, Department of Psychology and Neuroscience, Canada 3 Hangzhou Normal University, Center for Cognition and Brain Disorders, China Inhibition of return (IOR) is a behavioral phenomenon wherein responses are inhibited to stimuli at locations that have been previously attended. To investigate the neural reference frame of IOR, an eye movement must be introduced between stimulus onsets. Previous work has demonstrated that IOR is represented in spatiotopic, rather than retinotopic, coordinates [Maylor & Hockey (1985). Inhibitory component of externally controlled covert orienting in visual space. J Exp Psychol Hum Percept Perform, 11, 777-787]. Event-related potentials (ERPs) have further demonstrated that reductions in the early sensory P1 component are associated with retinotopic, but not spatiotopic, cueing - even though IOR is only present for spatiotopic cueing [Satel, Wang, Hilchey, & Klein (2012). Examining the dissociation of retinotopic and spatiotopic inhibition of return with event-related potentials. Neurosci Lett, 52, 40-44]. Here, we have expanded on previous designs by incorporating: 1) online eye tracking to ensure appropriate oculomotor behavior throughout trials, 2) both upper and lower visual field starting positions to avoid confounds associated with differential processing across hemifields, 3) an early eye movement condition to compare IOR when cueing is retinotopic, spatiotopic, and overlapping, 4) catch trials to discourage anticipatory responses, and 5) early target trials to ensure attention is not entirely focused upon central fixation during cue onset. Results show the expected pattern of spatiotopic IOR (11 ms, p < 0.01) without P1 reductions, non-significant retinotopic IOR (6 ms, ns) with P1 reductions, and strong IOR (43 ms, p < 0.001) with P1 reductions when retinotopic and spatiotopic representations overlap. These results continue to support the hypothesis that IOR is represented in spatiotopic coordinates and that retinotopic IOR is simply a remnant of repeated sensory stimulation in retinotopic coordinate space. Keywords: Attention, Event-related potentials, inhibition of return, spatiotopic, retinotopic Conference: XII International Conference on Cognitive Neuroscience (ICON-XII), Brisbane, Queensland, Australia, 27 Jul - 31 Jul, 2014. Presentation Type: Poster Topic: Attention Citation: Satel J, Hilchey M, Wang Z and Klein R (2015). Dissociating the neural mechanisms underlying spatiotopic and retinotopic inhibition of return: An investigation using eye tracking and electroencephalography. Conference Abstract: XII International Conference on Cognitive Neuroscience (ICON-XII). doi: 10.3389/conf.fnhum.2015.217.00340 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 19 Feb 2015; Published Online: 24 Apr 2015. * Correspondence: Dr. Jason Satel, University of Nottingham Malaysia Campus, School of Psychology, Semenyih, Malaysia, jsatel@gmail.com Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Jason Satel Matthew D. Hilchey Zhiguo Wang Raymond M. Klein Google Jason Satel Matthew D. Hilchey Zhiguo Wang Raymond M. Klein Google Scholar Jason Satel Matthew D. Hilchey Zhiguo Wang Raymond M. Klein PubMed Jason Satel Matthew D. Hilchey Zhiguo Wang Raymond M. Klein Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.