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The presaccadic preview of a peripheral target enhances the efficiency of its postsaccadic processing, termed the extrafoveal preview effect. Peripheral visual performance-and thus the quality of the preview-varies around the visual field, even at isoeccentric locations: It is better along the horizontal than vertical meridian and along the lower than upper vertical meridian. To investigate whether these polar angle asymmetries influence the preview effect, we asked human participants to preview four tilted gratings at the cardinals, until a central cue indicated which one to saccade to. During the saccade, the target orientation either remained or slightly changed (valid/invalid preview). After saccade landing, participants discriminated the orientation of the (briefly presented) second grating. Stimulus contrast was titrated with adaptive staircases to assess visual performance. Expectedly, valid previews increased participants' postsaccadic contrast sensitivity. This preview benefit, however, was inversely related to polar angle perceptual asymmetries; largest at the upper, and smallest at the horizontal meridian. This finding reveals that the visual system compensates for peripheral asymmetries when integrating information across saccades, by selectively assigning higher weights to the less-well perceived preview information. Our study supports the recent line of evidence showing that perceptual dynamics around saccades vary with eye movement direction.

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Our interest was to evaluate changes in fixation duration as a function of time-on-task (TOT) during a random saccade task. We employed a large, publicly available dataset. The frequency histogram of fixation durations was multimodal and modelled as a Gaussian mixture. For this specific task, we found five fixation types. The "ideal" response would be a single accurate saccade after each target movement, with a typical saccade latency of 200-250 msec, followed by a long fixation (> 800 msec) until the next target jump. We found fixations like this, but they comprised only 10% of all fixations and were the first fixation after target movement only 23.4% of the time. More frequently (57.4% of the time), the first fixation after target movement was short (117.7 msec mean) and was commonly followed by a corrective saccade. Across the entire 100 sec of the task, median total fixation duration decreased. This decrease was approximated with a power law fit with R2 = 0.94. A detailed examination of the frequency of each of our five fixation types over time on task (TOT) revealed that the three shortest duration fixation types became more and more frequent with TOT whereas the two longest fixations became less and less frequent. In all cases, the changes over TOT followed power law relationships, with R2 values between 0.73 and 0.93. We concluded that, over the 100 second duration of our task, long fixations are common in the first 15 to 22 seconds but become less common after that. Short fixations are relatively uncommon in the first 15 to 22 seconds but become more and more common as the task progressed. Apparently. the ability to produce an ideal response, although somewhat likely in the first 22 seconds, rapidly declines. This might be related to a noted decline in saccade accuracy over time.

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The analysis of eye movements has proven valuable for understanding brain function and the neuropathology of various disorders. This research aims to utilize eye movement data analysis as a screening tool for differentiation between eight different groups of pathologies, including scholar, neurologic, and postural disorders. Leveraging a dataset from 20 clinical centers, all employing AIDEAL and REMOBI eye movement technologies this study extends prior research by considering a multi-annotation setting, incorporating information from recordings from saccade and vergence eye movement tests, and using contextual information (e.g. target signals and latency of the eye movement relative to the target and confidence level of the quality of eye movement recording) to improve accuracy while reducing noise interference. Additionally, we introduce a novel hybrid architecture that combines the weight-sharing feature of convolution layers with the long-range capabilities of the transformer architecture to improve model efficiency and reduce the computation cost by a factor of 3.36, while still being competitive in terms of macro F1 score. Evaluated on two diverse datasets, our method demonstrates promising results, the most powerful discrimination being Attention & Neurologic; with a macro F1 score of up to 78.8%; disorder. The results indicate the effectiveness of our approach in classifying eye movement data from different pathologies and different clinical centers accurately, thus enabling the creation of an assistant tool in the future.

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The subjective feeling of being the author of one's actions and the subsequent consequences is referred to as a sense of agency. Such a feeling is crucial for usability in human-computer interactions, where eye movement has been adopted, yet this area has been scarcely investigated. We examined how the temporal action-feedback discrepancy affects the sense of agency concerning eye movement. Participants conducted a visual search for an array of nine Chinese characters within a temporally-delayed gaze-contingent display, blurring the peripheral view. The relative delay between each eye movement and the subsequent window movement varied from 0 to 4,000 ms. In the control condition, the window played a recorded gaze behavior. The mean authorship rating and the proportion of "self" responses in the categorical authorship report ("self," "delayed self," and "other") gradually decreased as the temporal discrepancy increased, with "other" being rarely reported, except in the control condition. These results generally mirror those of prior studies on hand actions, suggesting that sense of agency extends beyond the effector body parts to other modalities, and two different types of sense of agency that have different temporal characteristics are simultaneously operating. The mode of fixation duration shifted as the delay increased under 200-ms delays and was divided into two modes at 200-500 ms delays. The frequency of 0-1.5° saccades exhibited an increasing trend as the delay increased. These results demonstrate the influence of perceived action-effect discrepancy on action refinement and task strategy.

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Our aim in this study was to understand how we perform visuospatial comparison tasks by analyzing ocular behavior and to examine how restrictions in macular or peripheral vision disturb ocular behavior and task performance. Two groups of 18 healthy participants with normal or corrected visual acuity performed visuospatial comparison tasks (computerized version of the elementary visuospatial perception [EVSP] test) (Pisella et al., 2013) with a gaze-contingent mask simulating either tubular vision (first group) or macular scotoma (second group). After these simulations of pathological conditions, all participants also performed the EVSP test in full view, enabling direct comparison of their oculomotor behavior and performance. In terms of oculomotor behavior, compared with the full view condition, alternation saccades between the two objects to compare were less numerous in the absence of peripheral vision, whereas the number of within-object exploration saccades decreased in the absence of macular vision. The absence of peripheral vision did not affect accuracy except for midline judgments, but the absence of central vision impaired accuracy across all visuospatial subtests. Besides confirming the crucial role of the macula for visuospatial comparison tasks, these experiments provided important insights into how sensory disorder modifies oculomotor behavior with or without consequences on performance accuracy.

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Humans explore visual scenes by alternating short fixations with saccades directing the fovea to points of interest. During fixation, the visual system not only examines the foveal stimulus at high resolution, but it also processes the extrafoveal input to plan the next saccade. Although foveal analysis and peripheral selection occur in parallel, little is known about the temporal dynamics of foveal and peripheral processing upon saccade landing, during fixation. Here we investigate whether the ability to localize changes across the visual field differs depending on when the change occurs during fixation, and on whether the change localization involves foveal, extrafoveal processing, or both. Our findings reveal that the ability to localize changes in peripheral areas of the visual field improves as a function of time after fixation onset, whereas localization accuracy for foveal stimuli remains approximately constant. Importantly, this pattern holds regardless of whether individuals monitor only foveal or peripheral stimuli, or both simultaneously. Altogether, these results show that the visual system is more attuned to the foveal input early on during fixation, whereas change localization for peripheral stimuli progressively improves throughout fixation, possibly as a consequence of an increased readiness to plan the next saccade.

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The regulation of emotions is a crucial facet of well-being and social adaptability, with explicit strategies receiving primary attention in prior research. Recent studies, however, emphasize the role of implicit emotion regulation, particularly implicating the ventromedial prefrontal cortex (VMPFC) in association with its implementation. This study delves into the nuanced role of the VMPFC through focality-optimized multichannel transcranial direct current stimulation (tDCS), shedding light on its causal involvement in implicit reappraisal. The primary goal was to evaluate the effectiveness of VMFPC-targeted tDCS and elucidate its role in individuals with high trait anxiety. Participants engaged in implicit and explicit emotion regulation tasks during multichannel tDCS targeting the VMPFC. The outcome measures encompassed negative emotion ratings, pupillary diameter, and saccade count, providing a comprehensive evaluation of emotion regulation efficiency. The intervention exhibited a notable impact, resulting in significant reductions in negative emotion ratings and pupillary reactions during implicit reappraisal, highlighting the indispensable role of the VMPFC in modulating emotional responses. Notably, these effects demonstrated sustained efficacy up to 1 day postintervention. This study underscores the potency of VMPFC-targeted multichannel tDCS in augmenting implicit emotion regulation. This not only contributes insights into the neural mechanisms of emotion regulation but also suggests innovative therapeutic avenues for anxiety disorders. The findings present a promising trajectory for future mood disorder interventions, bridging the gap between implicit emotion regulation and neural stimulation techniques.

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OBJECTIVE: To date the vast majority of research in the visual neurosciences have been forced to adopt a highly constrained perspective of the vision system in which stimuli are processed in an open-loop reactive fashion (i.e., abrupt stimulus presentation followed by an evoked neural response). While such constraints enable high construct validity for neuroscientific investigation, the primary outcomes have been a reductionistic approach to isolate the component processes of visual perception. In electrophysiology, of the many neural processes studied under this rubric, the most well-known is, arguably, the P300 evoked response. There is, however, relatively little known about the real-world corollary of this component in free-viewing paradigms where visual stimuli are connected to neural function in a closed-loop. While growing evidence suggests that neural activity analogous to the P300 does occur in such paradigms, it is an open question when this response occurs and what behavioral or environmental factors could be used to isolate this component. APPROACH: The current work uses convolutional networks to decode neural signals during a free-viewing visual search task in a closed-loop paradigm within an open-world virtual environment. From the decoded activity we construct fixation-locked response profiles that enable estimations of the variable latency of any P300 analogue around the moment of fixation. We then use these estimates to investigate which factors best reduce variable latency and, thus, predict the onset time of the response. We consider measurable, search-related factors encompassing top-down (i.e., goal driven) and bottom-up (i.e., stimulus driven) processes, such as fixation duration and salience. We also consider saccade size as an intermediate factor reflecting the integration of these two systems. MAIN RESULTS: The results show that of these factors only saccade size reliably determines the onset time of P300 analogous activity for this task. Specifically, we find that for large saccades the variability in response onset is small enough to enable analysis using traditional ensemble averaging methods. SIGNIFICANCE: The results show that P300 analogous activity does occur during closed-loop, free-viewing visual search while highlighting distinct differences between the open-loop version of this response and its real-world analogue. The results also further establish saccades, and saccade size, as a key factor in real-world visual processing.

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Contrast sensitivity (CS), which constrains human vision, decreases from fovea to periphery, from the horizontal to the vertical meridian, and from the lower vertical to the upper vertical meridian. It also depends on spatial frequency (SF), and the contrast sensitivity function (CSF) depicts this relation. To compensate for these visual constraints, we constantly make saccades and foveate on relevant objects in the scene. Already before saccade onset, presaccadic attention shifts to the saccade target and enhances perception. However, it is unknown whether and how it modulates the interplay between CS and SF, and if this effect varies around polar angle meridians. CS enhancement may result from a horizontal or vertical shift of the CSF, increase in bandwidth, or any combination. In addition, presaccadic attention could enhance CS similarly around the visual field, or it could benefit perception more at locations with poorer performance (i.e., vertical meridian). Here, we investigated these possibilities by extracting key attributes of the CSF of human observers. The results reveal that presaccadic attention (1) increases CS across SF, (2) increases the most preferred and the highest discernable SF, and (3) narrows the bandwidth. Therefore, presaccadic attention helps bridge the gap between presaccadic and postsaccadic input by increasing visibility at the saccade target. Counterintuitively, this CS enhancement was more pronounced where perception is better-along the horizontal than the vertical meridian-exacerbating polar angle asymmetries. Our results call for an investigation of the differential neural modulations underlying presaccadic perceptual changes for different saccade directions.

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This meta-analysis examined inhibitory control performance in the antisaccade task across mental disorders. Following PRISMA guidelines, we analyzed data from k = 146 studies (n = 13,807 participants) on antisaccade performance. Effect sizes were estimated using random-effects models and restricted maximum-likelihood estimation, with robustness tests for study heterogeneity and publication bias. Most disorders displayed elevated error rates, with schizophrenia showing the greatest impairments, followed by autism spectrum disorder, bipolar disorder and attention deficit hyperactivity disorder. Small to medium impairments were also found in eating disorders, major depressive disorder, obsessive-compulsive disorder and substance use disorder. Results were robust against corrections for publication bias and largely unaffected by confounding variables. Prolonged latencies were observed in schizophrenia, attention deficit hyperactivity disorder, bipolar disorder and obsessive compulsive disorder, with smaller and less robust effect sizes. Results indicate inhibitory control deficits in the antisaccade task across mental disorders, especially evident for error rates. While present in most disorders, results imply varying degrees of impairments, ranging from small to large in effect sizes, with largest impairments in schizophrenia.

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BACKGROUND:  There may be confusion about which canal is involved in patients with benign paroxysmal positional vertigo (BPPV), especially with those that have subtle findings. The study aimed to determine if video head impulse testing may be used in such patients as a diagnostic tool. Symptom scoring and treatment efficiency in BPPV are essential parts of the process. Therefore, inventories like "Dizziness Handicap Inventory" may be useful in this regard. METHODS:  Patients with posterior and lateral canal BPPV were included. Video head impulse testing was performed prior to treatment and 1 week after treatment. Vestibuloocular reflex (VOR) gains were noted and compared to the opposite side. The presence of correction saccades was noted as well. Also, pretreatment and posttreatment Dizziness Handicap Inventory scores were compared. RESULTS:  Fifty-seven patients were diagnosed with posterior canal BPPV, and sixteen were with horizontal canal BPPV. In patients with posterior canal BPPV, there was no difference between the involved canal VOR gains and the other canals on the same side (P=.639). The involved horizontal canal did not differ from the opposite horizontal canal. Patients with lateral canal BPPV show more significant improvement after treatment compared to patients with posterior canal BPPV. CONCLUSION:  Video head impulse testing may not be used to estimate the involved canal in BPPV; however, it may be used to evaluate the efficiency of the treatment, especially in the lateral canal.

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Many studies have attempted to identify the root cause of dyslexia. Different theories of dyslexia have proposed either a phonological, attentional, or visual deficit. While research has used eye-tracking to study dyslexia, only two previous studies have used the moving-window paradigm to explore the perceptual span in dyslexic reading, and none have done so in visual search. The present study analysed the perceptual span using both reading and visual search tasks to identify language-independent attentional impairments in dyslexics. We found equivocal evidence that the perceptual span was impaired in dyslexic reading and no evidence of impairment in visual search. However, dyslexic participants did show deficits in the visual search task, with lower search accuracy and shorter saccades compared with controls. These results lend support for a visual, rather than attentional or phonological, account of dyslexia.

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Evidence has demonstrated that athletes exhibit superior cognitive performance associated with executive control. In the oculomotor system, this function has been examined using the interleaved pro-saccade and anti-saccade task (IPAST), wherein participants, prior to target appearance, are instructed to either automatically look at the peripheral target (pro-saccade) or suppress the automatic response and voluntarily look in the opposite direction (anti-saccade). While the IPAST has provided much insight into sensorimotor and inhibitory processing, it has yet to be performed in athletes. Moreover, limited research has examined saccade metrics in athletes. Here, we examined saccade latency and movement kinematics in the IPAST among athletes (N = 40) and nonathletes (NON) (N = 40). Higher direction error rates were obtained in the anti-saccade compared to the pro-saccade condition, with no differences between athletes and NON noted. Significantly faster saccade latencies were observed in athletes compared to NON in both conditions, in addition to faster pro-saccades compared to anti-saccades. Furthermore, athletes showed significantly higher frequencies and faster latencies of express saccades compared to NON in correct pro-saccades. Additionally, athletes exhibited significantly faster latencies of express saccades compared to NON in erroneous anti-saccades. Differences in saccade metrics between athletes and NON were not seen. Overall, these findings demonstrate that athletes display altered saccade performance likely associated with sensorimotor and preparatory processing, highlighting the potential of using IPAST to objectively investigate sensorimotor and cognitive functions in athletes.

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It is well known that attention is captured by salient objects or events. The notion that attention is attracted by salience information present in the visual field is also at the heart of many influential models of attention. These models typically posit a hierarchy of saliency, suggesting that attention progresses from the most to the least salient item in the visual field. However, despite the significance of this claim in various models, research on eye movements challenges the idea that search strictly follows this saliency hierarchy. Instead, eye-tracking studies have suggested that saliency information has a transient impact, only influencing the initial saccade toward the most salient object, and only if executed swiftly after display onset. While these findings on overt eye movements are important, they do not address covert attentional processes occurring before a saccade is initiated. In the current series of experiments, we explored whether there was evidence for secondary capture-whether attention could be captured by another salient item after the initial capture episode. To explore this, we utilized displays with multiple distractors of varying levels of saliency. Our primary question was whether two distractors with different saliency levels would disrupt search more than a single, highly salient distractor. Across three experiments, clear evidence emerged indicating that two distractors interfered more with search than a single salient distractor. This observation suggests that following initial capture, secondary capture by the next most salient distractor occurred. These findings collectively support the idea that covert attention traverses the saliency hierarchy. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

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Predictive remapping of receptive fields (RFs) is thought to be one of the critical mechanisms for enforcing perceptual stability during eye movements. While RF remapping has been observed in several cortical areas, its role in early visual cortex and its consequences on the tuning properties of neurons have been poorly understood. Here, we track remapping RFs in hundreds of neurons from visual area V2 while subjects perform a cued saccade task. We find that remapping is widespread in area V2 across neurons from all recorded cortical layers and cell types. Furthermore, our results suggest that remapping RFs not only maintain but also transiently enhance their feature selectivity due to untuned suppression. Taken together, these findings shed light on the dynamics and prevalence of remapping in the early visual cortex, forcing us to revise current models of perceptual stability during saccadic eye movements.

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Purpose: Within the healthy population there is a large variation in the ability to perform smooth pursuit eye movements. Our purpose was to investigate the genetic and physiological bases for this variation. Methods: We carried out a whole-genome association study, recording smooth pursuit movements for 1040 healthy volunteers by infrared oculography. The primary phenotypic measure was root mean square error (RMSE) of eye position relative to target position. Secondary measures were pursuit gain, frequency of catch-up saccades, and frequency of anticipatory saccades. Ten percent of participants, chosen randomly, were tested twice, giving estimates of test-retest reliability. Results: No significant association was found with three genes previously identified as candidate genes for variation in smooth pursuit: DRD3, COMT, NRG1. A strong association (P = 3.55 × 10-11) was found between RMSE and chromosomal region 1q42.2. The most strongly associated marker (rs701232) lies in an intron of KCNK1, which encodes a two-pore-domain potassium ion channel TWIK-1 (or K2P1) that affects cell excitability. Each additional copy of the A allele decreased RMSE by 0.29 standard deviation. When a psychophysical test of visually perceived motion was used as a covariate in the regression analysis, the association with rs701232 did not weaken (P = 5.38 × 10-12). Conclusions: Variation in the sequence or the expression of the pH-dependent ion channel TWIK-1 is a likely source of variance in smooth pursuit. The variance associated with TWIK-1 appears not to arise from sensory mechanisms, because the use of a perceptual covariate left the association intact.

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A single bout of exercise enhances executive function (EF) and may relate to an increase in cerebral blood flow (CBF). A limitation in the current literature is that biologically female participants are underrepresented given some evidence that changes in hormone levels across the menstrual cycle impact physiological and psychological variables. Here, biologically female participants completed separate single bouts of moderate intensity exercise (80% of estimated lactate threshold) during the follicular (FOL) and luteal (LUT) phases of their menstrual cycle. In addition, biologically male participants completed a same duration/intensity exercise session. Middle cerebral artery velocity (MCAv) was used to estimate CBF and pre- and postexercise EF was assessed via the antisaccade task. Results showed that resting MCAv was larger in the LUT than FOL phase; however, the exercise-mediated increase in MCAv was equivalent between menstrual cycle phases, and between female and male participants. Antisaccade reaction times reliably decreased from pre- to postexercise and frequentist and non-frequentist statistics demonstrated that the magnitude of the decrease was equivalent across FOL and LUT phases, and between female and male participants. Thus, results evince that menstrual cycle status should not serve as a basis limiting biologically female participants' inclusion in research examining exercise and EF.

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When two peripheral objects are presented in close proximity, saccades towards one of these objects land at a weighted average location between the two objects. This phenomenon, known as the 'global effect' or 'saccade averaging', disappears when the distance between the objects increases. When objects are further apart, outside the averaging zone, saccades land on one of the objects with little or no saccade averaging. Although it is known that the strength of the global effect is dependent on the specific features of the two objects, it is unclear if the size of the zone in which averaging can occur (i.e., the averaging zone) is adaptive. The aim of the current study was to investigate whether the size of the averaging zone adapts to variations in object luminance contrast of the objects. In order to systematically assess changes in the averaging zone, in two experiments, observers made saccadic eye movements while the luminance of the target and the distractor varied. We report three major findings: 1) When a distractor was more luminant relative to the target, the averaging zone increased (Exp. 1). Notably, saccade averaging never entirely ceased to exist, even for remote distractors. 2) When target and distractor were equiluminant, the averaging zone did not change with absolute luminance (Exp. 2). 3) Higher (relative and absolute) luminance increased the averaging zone especially for shorter saccadic response times (SRT). We conclude that the averaging zone is adaptive and becomes larger with increasing relative luminance and especially when SRTs are short.

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Visual processing differs between the foveal and peripheral visual field. These differences can lead to different appearances of objects in the periphery and the fovea, posing a challenge to perception across saccades. Differences in the appearance of visual features between the peripheral and foveal visual field may bias change discrimination across saccades. Previously it has been reported that spatial frequency (SF) appears higher in the periphery compared to the fovea (Davis et al., 1987). In this study, we investigated the visual appearance of SF before and after a saccade and the discrimination of SF changes during saccades. In addition, we tested the contributions of pre- and postsaccadic information to change discrimination performance. In the first experiment, we found no differences in the appearance of SF before and after a saccade. However, participants showed a clear bias to report SF increases. Interestingly, a 200-ms postsaccadic blank improved the precision of the responses but did not affect the bias. In the second experiment, participants showed lower thresholds for SF increases than for decreases, suggesting that the bias in the first experiment was not just a response bias. Finally, we asked participants to discriminate the SF of stimuli presented before a saccade. Thresholds in the presaccadic discrimination task were lower than in the change discrimination task, suggesting that transsaccadic change discrimination is not merely limited by presaccadic discrimination in the periphery. The change direction bias might stem from more effective masking or overwriting of the presaccadic stimulus by the postsaccadic low SF stimulus.

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