Role Of Eye Movements Research Articles

The Role of Eye Movements in the Process of Silicone Oil Emulsification After Vitreoretinal Surgery

Emulsification is a feared and common complication of the use of silicone oil (SO) as tamponade fluid after vitrectomy as it potentially associated with significant risks to ocular health, including elevated intraocular pressure (IOP), glaucoma, corneal and retinal changes. The aim of this study was to investigate the role and interplay of physical factors on the formation of SO emulsion. Experiments were performed in a model of the vitreous chamber with a realistic shape, filled with SO and an aqueous solution containing different concentrations of albumin, an endogenous protein known to modify the interfacial properties between SO and aqueous solutions. The model was subjected to harmonic and saccadic rotations and kept at body temperature. Results indicated that no emulsions were detected in the absence of albumin in the aqueous solution, while the presence of the protein facilitated emulsion formation, acting as a surfactant. Mechanical energy from eye movements was also found to be a key mechanism to produce emulsification, with higher mechanical energy provided to the system leading to smaller droplet sizes. The emulsions formed were stable over extended times. This study highlights the complex interplay of factors influencing SO emulsification in the vitreous chamber. A better understanding of the mechanisms underlying SO emulsification is crucial for developing strategies to mitigate SO emulsion and the related complications.

Time Compression Induced by Voluntary-Action and Its Underlying Mechanism: The Role of Eye Movement in Intentional Binding (IB)

Time Compression Induced by Voluntary-Action and Its Underlying Mechanism: The Role of Eye Movement in Intentional Binding (IB)

The role of eye movements in perceiving vehicle speed and time-to-arrival at the roadside

To avoid collisions, pedestrians depend on their ability to perceive and interpret the visual motion of other road users. Eye movements influence motion perception, yet pedestrians’ gaze behavior has been little investigated. In the present study, we ask whether observers sample visual information differently when making two types of judgements based on the same virtual road-crossing scenario and to which extent spontaneous gaze behavior affects those judgements. Participants performed in succession a speed and a time-to-arrival two-interval discrimination task on the same simple traffic scenario—a car approaching at a constant speed (varying from 10 to 90 km/h) on a single-lane road. On average, observers were able to discriminate vehicle speeds of around 18 km/h and times-to-arrival of 0.7 s. In both tasks, observers placed their gaze closely towards the center of the vehicle’s front plane while pursuing the vehicle. Other areas of the visual scene were sampled infrequently. No differences were found in the average gaze behavior between the two tasks and a pattern classifier (Support Vector Machine), trained on trial-level gaze patterns, failed to reliably classify the task from the spontaneous eye movements it elicited. Saccadic gaze behavior could predict time-to-arrival discrimination performance, demonstrating the relevance of gaze behavior for perceptual sensitivity in road-crossing.

The role of eye movements, attention, and hand movements on age-related differences in pegboard tests.

Well-documented manual dexterity impairments in older adults may critically depend on the processing of visual information. The purpose of this study was to determine age-related changes in eye and hand movements during commonly used pegboard tests and the association with manual dexterity impairments in older adults. The relationship between attentional deficits and manual dexterity was also assessed. Eye movements and hand kinematics of 20 young (20-38 yr) and 20 older (65-85 yr) adults were recorded during 9-Hole Pegboard, Grooved Pegboard, and a visuospatial dual test. Results were compared with standardized tests of attention (The Test of Everyday Attention and Trail Making Test) that assess visual selective attention, sustained attention, attentional switching, and divided attention. Hand movement variability was 34% greater in older versus young adults when placing the pegs into the pegboard and this was associated with decreased pegboard performance, providing further evidence that increased movement variability plays a role in dexterity impairments in older adults. Older adults made more corrective saccades and spent less time gazing at the pegboard than young adults, suggesting altered visual strategies in older compared with young adults. The relationship between pegboard completion time and Trail Making Test B demonstrates an association between attentional deficits and age-related pegboard impairments. Results contribute novel findings of age-associated changes in eye movements during a commonly used manual dexterity task and offer insight into potential mechanisms underlying hand motor impairments in older adults.NEW & NOTEWORTHY This eye tracking study contributes novel findings of age-associated changes in eye movements during the commonly used pegboard tests of manual dexterity, including a greater number of corrective saccades and lesser time gazing at the pegboard holes in older compared with young adults. An association between attentional deficits and dexterity impairments in older adults is also highlighted. Results shed light on potential mechanisms underlying well-documented motor deficits in older adults.

Role of the frontal eye field in human pupil and saccade orienting responses.

The appearance of a salient stimulus evokes a series of orienting responses including saccades and pupil size to prepare the body for appropriate action. The midbrain superior colliculus (SC) that receives critical control signals from the frontal eye field (FEF) is hypothesized to coordinate all components of orienting. It has shown recently that the FEF, together with the SC, is also importantly involved in the control of pupil size, in addition to its well-documented role in eye movements. Although the role of the FEF in pupil size is demonstrated in monkeys, its role in human pupil responses and the coordination between pupil size and saccades remains to be established. Through applying continuous theta-burst stimulation over the right FEF and vertex, we investigated the role of the FEF in human pupil and saccade responses evoked by a salient stimulus, and the coordination between pupil size and saccades. Our results showed that neither saccade reaction times (SRT) nor pupil responses evoked by salient stimuli were modulated by FEF stimulation. In contrast, the correlation between pupil size and SRTs in the contralateral stimulus condition was diminished with FEF stimulation, but intact with vertex stimulation. Moreover, FEF stimulation effects between saccade and pupil responses associated with salient stimuli correlated across participants. This is the first transcranial magnetic stimulation (TMS) study on the pupil orienting response, and our findings suggest that human FEF was involved in coordinating pupil size and saccades, but not involved in the control of pupil orienting responses.

Eye movements to absent objects during mental imagery and visual memory in immersive virtual reality

The role of eye movements in mental imagery and visual memory is typically investigated by presenting stimuli or scenes on a two-dimensional (2D) computer screen. When questioned about objects that had previously been presented on-screen, people gaze back to the location of the stimuli, even though those regions are blank during retrieval. It remains unclear whether this behavior is limited to a highly controlled experimental setting using 2D screens or whether it also occurs in a more naturalistic setting. The present study aims to overcome this shortcoming. Three-dimensional (3D) objects were presented along a circular path in an immersive virtual room. During retrieval, participants were given two tasks: to visualize the objects, which they had encoded before, and to evaluate a statement about visual details of the object. We observed longer fixation duration in the area, on which the object was previously displayed, when compared to other possible target locations. However, in 89% of the time, participants fixated none of the predefined areas. On the one hand, this shows that looking at nothing may be overestimated in 2D screen-based paradigm, on the other hand, the looking at nothing effect was still present in the 3D immersive virtual reality setting, and thus it extends external validity of previous findings. Eye movements during retrieval reinstate spatial information of previously inspected stimuli.

Eyes Wide Shut: Gaze dynamics without vision, Symposium 6 at the 20th European Conference on Eye Movement Research (ECEM) in Alicante, 21.8.2019.

The human ability for visualization extends far beyond the physical items that surround us. We are able to dismiss the constant influx of photons hitting our retinas, and instead picture the layout of our kindergarten classroom, envision the gently swaying palm trees of our dream vacation, or foresee the face of a yet-to-be-born child. As we inspect imaginary objects and people with our mind’s eye, our corporeal eyeballs latch onto the fantasy. Research has found that our eyes can move as if seeing, even when there is nothing to look at. Thus, gaze explorations in the absence of actual vision have been reported in many contexts, including in visualization and memory tasks, and perhaps even during REM sleep. This symposium will present the manifold aspects of gaze dynamics in conditions when the visual input is impoverished or altogether absent. Presentations will address the characteristics of large and small eye movements during imagined and remembered scenes, the impact of visual field deficits on oculomotor control, and the role of eye movements in the future development of neural prosthetics for the blind.Video stream: https://vimeo.com/365522806

Eye Movements Actively Reinstate Spatiotemporal Mnemonic Content.

Eye movements support memory encoding by binding distinct elements of the visual world into coherent representations. However, the role of eye movements in memory retrieval is less clear. We propose that eye movements play a functional role in retrieval by reinstating the encoding context. By overtly shifting attention in a manner that broadly recapitulates the spatial locations and temporal order of encoded content, eye movements facilitate access to, and reactivation of, associated details. Such mnemonic gaze reinstatement may be obligatorily recruited when task demands exceed cognitive resources, as is often observed in older adults. We review research linking gaze reinstatement to retrieval, describe the neural integration between the oculomotor and memory systems, and discuss implications for models of oculomotor control, memory, and aging.

Randomized Controlled Trial: EMDR Early Intervention With and Without Eye Movements for Learned Helplessness State

Learned helplessness (LH) is considered a psychological trait, which occurs after repeated exposure to aversive and uncontrollable situations (Seligman, 1975). Such an exposure is found to lead motivational, cognitive, and emotional deficits. LH has also been linked to different psychological disorders such as depression, anxiety, posttraumatic stress disorder (PTSD), and trauma-related depression. Eye movement desensitization and reprocessing (EMDR) therapy has been accepted as an efficacious treatment for PTSD, but evidence for its effectiveness as an early intervention is still preliminary. Also, there is some uncertainty regarding the role of eye movements in EMDR. The current randomized controlled study investigated whether a single 15-minute session of EMDR's Recent Traumatic Episode Protocol (R-TEP) could reduce the effects of laboratory-induced LH. The study further investigated whether R-TEP without eye movements would have the same effect. Using established experimental tasks, an LH state was induced via unsolvable maze tasks with effects measured by the participants' performance in solving anagrams. Results revealed that an LH state was successfully induced by the unsolvable mazes. R-TEP effectively reversed the negative effects of the LH state and was significantly more effective than no treatment controls and the R-TEP condition without eye movements, which was essentially a narrative exposure intervention. Results suggest that R-TEP can be successfully administered immediately following a distressful event, and that eye movements appear to be a necessary component of EMDR in reversing the cognitive, motivational, and/or emotional deficits induced by LH.

The role of eye movements in manual responses to social and nonsocial cues.

Gaze and arrow cues cause covert attention shifts even when they are uninformative. Nonetheless, it is unclear to what extent oculomotor behavior influences manual responses to social and nonsocial stimuli. In two experiments, we tracked the gaze of participants during the cueing task with nonpredictive gaze and arrow cues. In Experiment 1, the discrimination task was easy and eye movements were not necessary, whereas in Experiment 2 they were instrumental in identifying the target. Validity effects on manual response time (RT) were similar for the two cues in Experiment 1 and in Experiment 2, though in the presence of eye movements observers were overall slower to respond to the arrow cue compared with the gaze cue. Cue direction had an effect on saccadic performance before the discrimination was presented and throughout the duration of the trial. Furthermore, we found evidence of a distinct impact of the type of cue on diverse oculomotor components. While saccade latencies were affected by the type of cue, both before and after the target onset, saccade landing positions were not. Critically, the manual validity effect was predicted by the landing position of the initial eye movement. This work suggests that the relationship between eye movements and attention is not straightforward. In the presence of overt selection, saccade latency related to the overall speed of manual response, while eye movements landing position was closely related to manual performance in response to different cues.

Is perceiving bodily action?

One of the boldest claims one finds in the enactivist and embodied cognition literature is that perceiving is bodily action (PBA). Research on the role of eye movements in vision have been thought to support PBA, whereas research on paralysis has been thought to pose no challenge to PBA. The present paper, however, will argue just the opposite. Eye movement research does not support PBA, whereas paralysis research presents a strong challenge that seems not to have been fully appreciated.

Constitutive relevance in cognitive science: The case of eye movements and cognitive mechanisms

In this paper I assess whether the recently proposed “No De-Coupling” (NDC) theory of constitutive relevance in mechanisms is a useful tool to reconstruct constitutive relevance investigations in scientific practice. The NDC theory has been advanced as a framework theoretically superior to the mutual manipulability (MM) account of constitutive relevance in mechanisms but, in contrast to the MM account, has not yet been applied to detailed case studies. I argue that the NDC account is also applicable to empirical practice and that it fares better than the MM account on both theoretical and empirical grounds. I elaborate these claims in terms of applications of the NDC theory to two case studies of cognitive science research on the role of eye movements in mechanisms for cognitive capacities.

The influence of eye-movements on the development of a movement sequence representation during observational and physical practice

An experiment was conducted to examine the development of a movement sequence representation and the role of eye-movements during observational and physical practice. The task was to reproduce a 1300ms spatial-temporal pattern of a sequence of elbow flexions and extensions. An inter-manual transfer design with a retention and two effector transfer tests (contralateral limb) was used. The mirror transfer test required the same pattern of homologous muscle activation and a sequence of joint angles as experienced during the acquisition phase, and the non-mirror transfer test required the same visual-spatial pattern as performed or observed during acquisition. Participants were randomly assigned to one of four groups differing in eye-movements (free to use their eyes vs. instruction to fixate) and the practice type (observational practice vs. physical practice). The results indicated that permitting to use eye-movements facilitates sequence learning. This advantage was found on both practice types. The results of the transfer tests indicated that participants of the physical practice group who were permitted to use their eyes demonstrated superior transfer performance in the mirror transfer test, while participants in the observational practice group demonstrated better performance on the non-mirror transfer test. These findings indicated that eye-movements enhanced the development of a visual-spatial representation during observational practice as well as a motor representation during physical practice.

Modern Speed-Reading Apps Do Not Foster Reading Comprehension.

New computer apps are gaining popularity by suggesting that reading speeds can be drastically increased when eye movements that normally occur during reading are eliminated. This is done using rapid serial visual presentation (RSVP), where words are presented 1 at a time, thus preventing natural eye movements such as saccades, fixations, and regressions from occurring. Al- though the companies producing these apps suggest that RSVP reading does not yield comprehension deficits, research investigating the role of eye movements in reading documents shows the necessity of natural eye movements for accurate comprehension. The current study explored variables that may affect reading comprehension during RSVP reading, including text difficulty (6th grade and 12th grade), text presentation speed (static, 700 wpm, and 1,000 wpm), and working memory capacity (WMC). Consistent with recent work showing a tenuous relationship between comprehension and WMC, participants' WMC did not predict comprehension scores. Instead, comprehension was most affected by reading speed: Static text was associated with superior performance, relative to either RSVP reading condition. Furthermore, slower RSVP speeds yielded better verbatim comprehension, and faster speeds benefited inferential comprehension.

Implicit Learning of Spatial Configuration Occurs without Eye Movement

AbstractStudies have demonstrated that eye movements enhance visual memory. However, the role of eye movement in implicit learning is not clear. We investigated whether implicit learning of spatial configuration requires eye movement using the contextual cueing paradigm. Eye movements were restricted by instructing participants to maintain fixation on the center of a display during a visual search. The results demonstrated that contextual cueing occurs even without eye movements. Furthermore, contextual cueing effects were obtained more rapidly when eye movements were restricted compared to when eye movements were allowed. The findings suggest that eye movements mediate the learning progress in contextual cueing: stabilization of spatial layout representation by restriction of eye movements induces a rapid learning of configuration.

Learning to search. The importance of eye movements in the decrease of response times during a visual choice reaction time task

Reaction times are often used as an indicator of the efficiency of the processes in thecentral nervous system. While extensive research has been conducted on the possibleresponse time correlates, the role of eye movements in visual tasks is yet unclear. Here wereport data to support the role of eye movements during visual choice reaction time training.Participant performance, reaction times, and total session duration improved. Eyemovementsshowed expected changes in saccade amplitude and resulted in improvementin visual target searching.

Exposition on Eye Movements in Managerial Decision

Exploration on Managerial decision making has extended from Managerial decision behaviourist approach to cognitive approach that focuses on decision processes that ensue prior to response. In neural computational simulations, each Managerial decision during decision task is represented by node of neural activity. Decision related neural activity has components of intensification of activity and decision inception for neural activity to overcome for decision to be completed. One way to investigate computational Managerial decision making is to scan positioning of Managerial decision behaviour leading to judgment point. Eye movements are central measure of Managerial decision. Eye movements are indissolubly linked to optical consideration as both are prime tools for choosing stimulating shares of chromatic prospects for enriched perceptual and rational processing. Investigating eye movements is expedient in providing evidence of orientation of Managerial decision Managerial decision behaviour replicating computational decision during decision formation. Role of eye movements, intentional or reflex, help in gaining, possessing and tracing visual inducements, during Managerial decision formation is not entirely clear. Current proof suggests that orientation of eye movement itself may not be an essential constituent. Rather, it can be as a result of intensification in contact to incitement as an e influential factor in Managerial decision formation. Purpose of present scholarship is to survey foregoing conclusions that eye movements have contributory stimulus on Managerial decision formation in a rational fashion. We review experiential studies that employ eye movement monitoring as process tracing and tracking method with gazing in Managerial decision-making research. Using Kowlerian Model, we present an investigation that explains experimental methods and analysis with contemporary eye tracking savoir-faire. This paper countenances a specific hypothesis about role of eye movements in Managerial decision Managerial decision; understanding how eye movements are premeditated, carried out notwithstanding recurrent vicissitudes in optical assortment that eye movement harvest. One major effort is understanding how should Managers’ decide, deal with risks and uncertainties, create options better than originally available, potential responses to problems and evaluate strengths and weaknesses of each prospective action using apparatus of eye tracking/tracing and gazing.

The Interaction Between Vision and Eye Movements †.

The existence of a central fovea, the small retinal region with high analytical performance, is arguably the most prominent design feature of the primate visual system. This centralization comes along with the corresponding capability to move the eyes to reposition the fovea continuously. Past research on visual perception was mainly concerned with foveal vision while the observers kept their eyes stationary. Research on the role of eye movements in visual perception emphasized their negative aspects, for example, the active suppression of vision before and during the execution of saccades. But is the only benefit of our precise eye movement system to provide high acuity of the small foveal region, at the cost of retinal blur during their execution? In this review, I will compare human visual perception with and without saccadic and smooth pursuit eye movements to emphasize different aspects and functions of eye movements. I will show that the interaction between eye movements and visual perception is optimized for the active sampling of information across the visual field and for the calibration of different parts of the visual field. The movements of our eyes and visual information uptake are intricately intertwined. The two processes interact to enable an optimal perception of the world, one that we cannot fully grasp by doing experiments where observers are fixating a small spot on a display.

The role of eye movements in the ‘Spine Drift” illusion perception

The role of eye movements in the ‘Spine Drift” illusion perception

Implications of Lateral Cerebellum in Proactive Control of Saccades.

Although several lines of evidence establish the involvement of the medial and vestibular parts of the cerebellum in the adaptive control of eye movements, the role of the lateral hemisphere of the cerebellum in eye movements remains unclear. Ascending projections from the lateral cerebellum to the frontal and parietal association cortices via the thalamus are consistent with a role of these pathways in higher-order oculomotor control. In support of this, previous functional imaging studies and recent analyses in subjects with cerebellar lesions have indicated a role for the lateral cerebellum in volitional eye movements such as anti-saccades. To elucidate the underlying mechanisms, we recorded from single neurons in the dentate nucleus of the cerebellum in monkeys performing anti-saccade/pro-saccade tasks. We found that neurons in the posterior part of the dentate nucleus showed higher firing rates during the preparation of anti-saccades compared with pro-saccades. When the animals made erroneous saccades to the visual stimuli in the anti-saccade trials, the firing rate during the preparatory period decreased. Furthermore, local inactivation of the recording sites with muscimol moderately increased the proportion of error trials, while successful anti-saccades were more variable and often had shorter latency during inactivation. Thus, our results show that neuronal activity in the cerebellar dentate nucleus causally regulates anti-saccade performance. Neuronal signals from the lateral cerebellum to the frontal cortex might modulate the proactive control signals in the corticobasal ganglia circuitry that inhibit early reactive responses and possibly optimize the speed and accuracy of anti-saccades. Although the lateral cerebellum is interconnected with the cortical eye fields via the thalamus and the pons, its role in eye movements remains unclear. We found that neurons in the caudal part of the lateral (dentate) nucleus of the cerebellum showed the increased firing rate during the preparation of anti-saccades. Inactivation of the recording sites modestly elevated the rate of erroneous saccades to the visual stimuli in the anti-saccade trials, while successful anti-saccades during inactivation tended to have a shorter latency. Our data indicate that neuronal signals in the lateral cerebellum may proactively regulate anti-saccade generation through the pathways to the frontal cortex, and may inhibit early reactive responses and regulate the accuracy of anti-saccades.