Perception of interpersonal distance and social distancing before and during COVID-19 pandemic

Since COVID-19 is easily transmitted among people in close physical proximity, the focus of epidemiological policy during the COVID-19 crisis included major restrictions on interpersonal distance. However, the way in which distance restrictions affected spatial perception is unclear. In the current study, we examined interpersonal distance preferences and perceptions at three time points: pre-pandemic, early post-pandemic, and late post-pandemic. The results indicate that following the pandemic outbreak, people perceived others as farther away than they actually were, suggesting that the distance restrictions were associated with an enlargement of perceived interpersonal distance. Interestingly, however, people maintained the same distance from one another as before the outbreak, indicating no change in actual distance behavior due to the risk of infection. These findings suggest that COVID-19 was associated with a change in the way distance is perceived, while in practice, people maintain the same distance as before. In contrast, COVID-related anxiety predicted both a preference for maintaining a greater distance and a bias toward underestimating perceived distance from others. Thus, individuals who were highly fearful of COVID-19 perceived other people to be closer than they actually were and preferred to maintain a larger distance from them. The results suggest that subjective risk can lead to an increased perception of danger and a subsequent change in behavior. Taken together, even when behaviors should logically change, the decision-making process can be based on distorted perceptions. This insight may be used to predict public compliance.

Atypical Impact of Action Effect Delay on Motor Performance in Autism

Atypical sensory perception and motor impairments are primary features of autism spectrum disorder (ASD) that indicate atypical development and predict social and non-social challenges. However, their link is poorly understood. Sensory perception is often integrated with motor processes when a sensory effect is temporally contiguous with the motor response. Such sensory-motor coupling further improves motor behavior. Previous studies indicate alterations in sensory perception of action-effect temporal contiguity in ASD, which bares the question of how it may impact motor performance. People diagnosed with ASD and typically developed (TD) participants performed a speeded reaction-time task previously established to capture the facilitating impact of action's perceptual effect on motor response selection. The sensitivity of this mechanism to delays in the effect was measured, manipulating the action-effect temporal contiguity in a within-subject design. An immediate action effect (compared to a No-effect condition) facilitated response selection in the TD group. This facilitation effect was evident in the ASD group but did not show the typical sensitivity to the effect delay. While in the TD group, RT was shorter in the short (225ms) compared to the long (675ms) action effect delay condition, this distinguished pattern was absent in the ASD group. The findings provide supporting evidence that atypical motor performance in ASD results, at least in part, from an altered sensory perception of action effect temporal contiguity. We discuss the results in light of the reduced perceptual specialization account in ASD and its potential for undermining adaptive sensorimotor processes.

Refinement of face representations by exposure reveals different time scales of biases in face processing

Experience modulates face processing abilities so that face discrimination and recognition improve with development, especially for more frequently experienced faces (e.g., own-race faces). Although advanced models describe how experience generally modulates perception, the mechanism by which exposure refines internal perceptual representations of faces is unknown. To address this issue, we investigated the effect of short- and long-term experienced stimulus history on face processing. Participants performed same-different judgments in a serial discrimination task where two consecutive faces were drawn from a distribution of morphed faces. Use of stimulus statistics was measured by testing the gravitation of face representations towards the mean of a range of morphed faces around which they were sampled (regression-to-the-mean). The results demonstrated regression of face representations towards the experienced mean and the retention of stimulus statistics over days. In trials where regression facilitated discrimination, the bias diminished the otherwise disadvantage of other-race over own-races faces. The dynamics of the perceptual bias, probed by trial-by-trial performance, further indicated different timescales of the bias, depending on perceptual expertise: people with weak face-recognition skills showed the use of a stable reference, built on long-term statistics accumulated over many trials, along with an updating of this reference by recent trials. In contrast, the strong face recognizers showed a different pattern where sequential effects mostly contributed to discrimination, with relatively minimal reliance on the long-term average for other-race faces. The findings suggest a mechanism by which exposure refines face representations and reveal, for the first time in adults, associations between levels of specialization of perceptual representations and the extent to which these representations become narrowly tuned.

Contextual effects on duration perception are modality-specific

The perception of magnitude, crucial for a mental representation of the physical world, is often subject to significant biases. Many of these biases are similar across sensory modalities, implying a generalized perception of magnitude. At the same time, some physical magnitudes might have a dedicated modality-specific calibration mechanism to enhance perceptual sensitivity. We examined this question of generalized versus modality-specific processes testing between- and within-modalities' contextual effects on the perception of magnitude. In a constant stimuli procedure, a central standard was embedded in shorter and longer contextual standards. These contextual standards were sampled in either a relatively wider or narrower range of durations. Participants were asked to determine which of the two consecutive durations was longer. Better perceptual sensitivity was found for narrower contexts, with stronger effects in trials in which the standard was presented first. Interestingly, narrower context enhanced sensitivity for standards within the same modality but had no effect on standards of another modality. A unidirectional transfer of contextual effects was observed under certain conditions from auditory, the dominant modality in performing temporal judgments, to vision. These results suggest that the perceptual system appears to develop modality-specific calibration mechanisms, most likely, to enhance perceptual sensitivity and maintain sensory specialization. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

An effect that counts: Temporally contiguous action effect enhances motor performance

An action-effect temporal contiguity holds essential information for motor control. Emerging accounts suggest that the temporally contiguous action effect is rewarding in and of itself, further promoting the development of motor representations and reinforcing the selection of the relevant motor program. The current study follows these theoretical and empirical indications to directly investigate the promoting impact of action effect temporal contiguity on motor performance. In two experiments, participants rapidly moved toward a target location on a computer monitor and clicked on the target with their mouse key as quickly and accurately as possible. Their click response triggered a perceptual effect (a brief flash) on the target. To examine the impact of action-effect delay and its temporal contiguity context, we manipulated action-effect delay in two temporal contiguity contexts-long versus short lag conditions. The findings demonstrate that the temporally contiguous perceptual effect enhances motor performance as indicated by end-point precision and movement speed. In addition, a substantial impact of the temporal contiguity context was observed. Namely, we found enhanced motor performance after an ambiguous (300 ms) action-effect delay sampled from short compared to long lag distributions (Experiment 1). This pattern was inconclusive for an immediate action effect (Experiment 2). We discuss the findings in the context of reinforcement from action effect and movement control.

Intact Utilization of Contextual Information in Speech Categorization in Autism

Current theories of Autism Spectrum Disorder (ASD) suggest atypical use of context in ASD, but little is known about how these atypicalities influence speech perception. We examined the influence of contextual information (lexical, spectral, and temporal) on phoneme categorization of people with ASD and in typically developed (TD) people. Across three experiments, we found that people with ASD used all types of contextual information for disambiguating speech sounds to the same extent as TD; yet they exhibited a shallower identification curve when phoneme categorization required temporal processing. Overall, the results suggest that the observed atypicalities in speech perception in ASD, including the reduced sensitivity observed here, cannot be attributed merely to the limited ability to utilize context during speech perception.

Weaker face recognition in adults with autism arises from perceptually based alterations

Face recognition has been shown to be impaired in autism spectrum disorders (ASD). However, it is still debated whether these face processing deficits arise from perceptually based alterations. We tested individuals with ASD and matched typically developing (TD) individuals using a delayed estimation task in which a single target face was shown either upright or inverted. Participants selected a face that best resembled the target face out of a cyclic space of morphed faces. To enable the disentanglement of visual from mnemonic processing, reports were required either following a 1 and 6 second retention interval, or simultaneously while the target face was still visible. Individuals with ASD made significantly more errors than TD individuals in both the simultaneous and delayed intervals, indicating that face recognition deficits in autism are also perceptual rather than strictly memory based. Moreover, individuals with ASD exhibited weaker inversion effects than the TD individuals, on all retention intervals. This finding, that was mostly evident in precision errors, suggests that contrary to the more precise representations of upright faces in TD individuals, individuals with ASD exhibit similar levels of precision for inverted and upright faces, for both simultaneous and delayed conditions. These results suggest that weakened memory for faces reported in ASD may be secondary to an underlying perceptual deficit in face processing.

Sensory Perception in Autism: What Can We Learn?

Autism is a neurodevelopmental disorder of unknown etiology. Recently, there has been a growing interest in sensory processing in autism as a core phenotype. However, basic questions remain unanswered. Here, we review the major findings and models of perception in autism and point to methodological issues that have led to conflicting results. We show that popular models of perception in autism, such as the reduced prior hypothesis, cannot explain the many and varied findings. To resolve these issues, we point to the benefits of using rigorous psychophysical methods to study perception in autism. We advocate for perceptual models that provide a detailed explanation of behavior while also taking into account factors such as context, learning, and attention. Furthermore, we demonstrate the importance of tracking changes over the course of development to reveal the causal pathways and compensatory mechanisms. Finally, we propose a developmental perceptual narrowing account of the condition. Expected final online publication date for the Annual Review of Vision Science, Volume 8 is September 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

Individuals with autism show non-adaptive relative weighting of perceptual prior and sensory reliability

LAY ABSTRACT

Unique perceptual skills and abnormalities in perception have been extensively demonstrated in those with autism for many perceptual domains, accounting, at least in part, for some of the main symptoms. Several new hypotheses suggest that perceptual representations in autism are unrefined, appear less constrained by exposure and regularities of the environment, and rely more on actual concrete input. Consistent with these emerging views, a bottom-up, data-driven fashion of processing has been suggested to account for the atypical perception in autism. It is yet unclear, however, whether reduced effects of prior knowledge and top-down information, or rather reduced noise in the sensory input, account for the often-reported bottom-up mode of processing in autism. We show that neither is sufficiently supported. Instead, we demonstrate clear differences between autistics and neurotypicals in how incoming input is weighted against prior knowledge and experience in determining the final percept. Importantly, the findings tap central differences in perception between those with and without autism that are consistent across identified sub-clusters within each group.

Nonsymbolic-Magnitude Deficit in Adults With Developmental Dyscalculia: Evidence of Impaired Size Discrimination but Intact Size Constancy

Although researchers have debated whether a core deficit of nonsymbolic representation of magnitude underlies developmental dyscalculia (DD), research has mostly focused on numerosity processing. We probed the possibility of a general magnitude deficit in individuals with DD and asked whether sensitivity to size varied in contexts of depth ordering and size constancy. We measured full psychometric functions in size-discrimination tasks in 12 participants with DD and 13 control participants. Results showed that although people with DD exhibited veridical perceived magnitude, their sensitivity to size was clearly impaired. In contrast, when objects were embedded in depth cues allowing size-constancy computations, participants with DD demonstrated typical sensitivity to size. These results demonstrate a deficit in the perceptual resolutions of magnitude in DD. At the same time, the finding of an intact size constancy suggests that when magnitude perception is facilitated by implicit mandatory computations of size constancy, this deficit is no longer evident.

Double dissociation between perception and action in children

Previous research has demonstrated a functional dissociation between vision for perception and vision for action. However, the developmental trajectory of this functional dissociation is not well understood. We directly compared the sensitivity of grasping and perceptual estimations within the same experimental design to the real and illusory sizes of objects positioned in the Ponzo illusion display. Two different-sized objects were placed such that the differences between their real sizes and their perceived sizes were pitted against each other. Children aged 5-8 years and adults made perceptual size discriminations and then grasped (action) or estimated (perception) one of the objects based on its perceived size. Consistent with previous results, for the action task, grasping apertures of adults were scaled with the physical differences in the objects' sizes, even in trials where their overt perceptual decisions were deceived by the illusion. In contrast, perceptual estimations were robustly modulated by the illusion. Interestingly, children outperformed adults in their perceptual discriminations but exhibited adult-like behavior in grasping and in perceptual estimations of the objects, demonstrating a dissociation between perception and action. These results suggest that although the two visual functions are not operating at fully mature levels during childhood, some key mechanisms that support a dissociation between these functions are already in place.

Typical perceptual organization in autism: Perceptual grouping and spatial distortion

The extensive literature on global-local processing in people with autism spectrum disorder (ASD) has recently shifted from arguing for a processing impairment among those with ASD to positing an attenuated preference for global processing. One suggestion is that the fast extraction of the global gist is less efficient in ASD, in contrast to the superior attention-driven processing of local elements. To examine this claim of attenuated global processing, the present study tested how perceptual grouping affected the global organization of visual scenes, specifically testing the claim of less mandatory, more optional global processing in ASD. Participants judged the distance between grouped and ungrouped elements in displays in which illusory distortions were inherent in configurations exemplifying the Gestalt principles of organization. Results from six experiments manipulating different Gestalt cues showed a consistent pattern, indicating that for individuals with ASD, as for typically developed (TD) individuals, grouping processes are organizational in nature, incorporating the grouping of related elements while parsing these from other unrelated elements. This parsing is accompanied by distortions in the spatial relationships perceived in the visual scene. ASD participants exhibited an overall larger tendency to overestimate the distances, but they also demonstrated typical perceptual organization processes that were robust and mandatory and, as in neurotypicals, affected the perception of the whole scene. Autism Res 2019. © 2019 International Society for Autism Research, Wiley Periodicals, Inc. LAY SUMMARY: It is known that individuals with autism spectrum disorder (ASD) perceive the world in a different way than their typically developed (TD) peers. While TD individuals exhibit strong bias toward processing the global structure of visual scenes, individuals with ASD exhibit enhanced perception of the local elements. We showed that when the local and global levels are not competing, individuals with autism demonstrate robust global organization that operates even when not directly instructed.

Perception in autism does not adhere to Weber's law

Perceptual atypicalities are a widely acknowledged but poorly understood feature of autism. We demonstrate here a striking violation of one of the most adaptive psychophysical computations - Weber's law - in high-functioning individuals with autism. JNDs based on the best-fitting psychometric functions were measured for size visual judgments (Exp. 1), weight haptic discrimination (Exp. 2), and illusive perception of weight (brightness-weight illusion; Exp. 3). Results for the typically developed group confirmed Weber's law, demonstrating a linear increase in JNDs with intensity, resulting in constant fractions across intensities. The results for the ASD, in contrast, showed no scaling of JNDs with intensity; instead, fractions decreased linearly with intensity. In striking contrast to its consistency in typical perception, Weber's law does not hold for visual and haptic perception in autism. These robust modulations in psychophysical computations, demonstrated for different domains of perception, suggest a modality-independent, low-level mechanism driving altered perception in autism.

Reduced perceptual specialization in autism: Evidence from the other-race face effect

Emerging accounts of autism suggest that flexible and broadly tuned perceptual representations, presumably resulting from reduced specialization, may underlie atypical perception. Here, we examined the other-race effect (ORE) to study face processing specialization arising from specific experience with own-race faces. Face discrimination was tested for own- and other-race faces in typically developed individuals and in individuals with autism spectrum disorder (ASD). For each race, faces were morphed to vary discrimination difficulty, and orientation was manipulated to examine inversion effects. The ASD group displayed overall lower sensitivity and reduced inversion effects in processing faces. Importantly, the processing advantage for own-race faces was substantially smaller in this group, resulting specifically from the reduced specialization for the own-race faces. Moreover, the typical larger inversion effect for Caucasian faces was not observed in the ASD group; sensitivity to orientation was smaller and equivalent for the two face races. These more broadly tuned representations in autism may account for the overall weaker representations of faces and suggest, more broadly, that a failure in perceptual specialization may underlie atypical perception in autism. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Adults’ Markers of Face Processing Are Present at Age 6 and Are Interconnected Along Development

Recent studies on the development of face processing argue for a late, quantitative, domain-specific development of face processing, and face memory in particular. Most previous findings were based on separately tracking the developmental course of face perception skills, comparing performance across different age groups. Here, we adopted a different approach studying the mechanisms underlying the development of face processing by focusing on how different face skills are interrelated over the years (age 6 to adulthood). Specifically, we examined correlations within and between different categories of tasks: face domain-specific skills involving face recognition based on long-term representations (famous face), and short-term memory retention (Cambridge Face Memory Test), perceptual face-specific marker (inversion effect), global effects in scene perception (global–local task), and the perception of facial expressions. Factor analysis revealed that face identity skills have a similar pattern of interrelations throughout development, identifying two factors: a face domain-specific factor comprising adultlike markers of face processing and a general factor incorporating related, but nonspecific perceptual skills. Domain-specific age-related changes in face recognition entailing short- and long-term retention of face representations were observed, along with mature perceptual face-specific markers and more general perceptual effects predicting face perception skills already at age 6. The results suggest that the domain-specific changes in face processing are unlikely to result from developmental changes in perceptual skills driving face recognition. Instead, development may either involve improvement in the ability to retain face representations in memory or changes in the interactions between the perceptual representations of faces and their representations in long-term memory.

Emotional cues differently modulate visual processing of faces and objects

Ample evidence suggests that emotion affects visual perception. Here we asked how arousal, induced by emotional stimuli and modulated by anxiety trait, biases competition among stimuli to favor the perceptually conspicuous ones. We first demonstrated that negatively arousing pictures impaired subsequent discrimination of cars, but not the discrimination of faces, among individuals with high-trait anxiety. To directly demonstrate the role of attention in the emotional modulations of visual perception, we used a modified exogenous cuing task, showing that for anxious individuals, a negatively arousing cue elicited cost when processing cars but not faces. These results indicate that arousal biases attention toward perceptually salient stimuli, allowing those with high-trait anxiety to disengage attention from an arousing stimulus more easily when it is followed by a face. The results suggest that attention modulates the effects of emotion on perception, leading to higher resilience of high-priority stimuli to arousal-biased competition. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

The role of early visual input in the development of contour interpolation: the case of subjective contours

We tested the effect of early monocular and binocular deprivation of normal visual input on the development of contour interpolation. Patients deprived from birth by dense central cataracts in one or both eyes, and age-matched controls, discriminated between fat and thin shapes formed by either illusory or luminance-defined contours. Thresholds indicated the minimum amount of curvature (the fatness or thinness) required for discrimination of the illusory shape, providing a measure of the precision of interpolation. The results show that individuals deprived of visual input in one eye, but not those deprived in both eyes, later show deficits in perceptual interpolation. The deficits were shown mostly for weakly supported contours in which interpolation of contours between the inducers was over a large distance relative to the size of the inducers. Deficits shown for the unilateral but not for the bilateral patients point to the detrimental effect of unequal competition between the eyes for cortical connections on the later development of the mechanisms underlying contour interpolation.

Strong Bias Towards Analytic Perception in ASD Does not Necessarily Come at the Price of Impaired Integration Skills

We first demonstrated analytic processing in ASD under conditions in which integral processing seems mandatory in TD observers, a pattern that is often taken to indicate a local default processing in ASD. However, this processing bias does not inevitably come at the price of impaired integration skills. Indeed, examining the same group of individuals with ASD on a task with explicit demands for integrated representations, Experiment 2 showed that the same observers with ASD demonstrated intact spatial integration. The results further showed that performance was not only quantitatively, but also qualitatively comparable to that of TD observers, demonstrating the sensitivity of integration in ASD to the same interactive effects of Gestalt cues.

Evidence for similar early but not late representation of possible and impossible objects

The perceptual processes that mediate the ability to efficiently represent object 3D structure are still not fully understood. The current study was aimed to shed light on these processes by utilizing spatially possible and impossible objects that could not be created in real 3D space. Despite being perceived as exceptionally unusual, impossible objects still possess fundamental Gestalt attributes and valid local depth cues that may support their initial successful representation. Based on this notion and on recent findings from our lab, we hypothesized that the initial representation of impossible objects would involve common mechanisms to those mediating typical object perception while the perceived differences between possible and impossible objects would emerge later along the processing hierarchy. In Experiment 1, participants preformed same/different classifications of two markers superimposed on a display containing two objects (possible or impossible). Faster reaction times were observed for displays in which the markers were superimposed on the same object (“object-based benefit”). Importantly, this benefit was similar for possible and impossible objects, suggesting that the representations of the two object categories rely on similar perceptual organization processes. Yet, responses for impossible objects were slower compared to possible objects. Experiment 2 was designed to examine the origin of this effect. Participants classified the location of two markers while exposure duration was manipulated. A similar pattern of performance was found for possible and impossible objects for the short exposure duration, with differences in accuracy between these two types of objects emerging only for longer exposure durations. Overall, these findings provide evidence that the representation of object structure relies on a multi-level process and that object impossibility selectively impairs the rendering of fine-detailed description of object structure.

The development of contour interpolation: evidence from subjective contours

Adults are skilled at perceiving subjective contours in regions without any local image information (e.g., Ginsburg, 1975; Kanizsa, 1976). Here we examined the development of this skill and the effect thereon of the support ratio (i.e., the ratio of the physically specified contours to the total contour length). Children (6-, 9-, and 12-year-olds) and adults discriminated between fat and skinny shapes formed by subjective or luminance-defined contours. By 9 years of age, children were as sensitive as adults to small differences in luminance-defined contours, but not until 12 years of age were children as sensitive as adults in performing the same task with subjective contours. Remarkably, 6-year-olds' sensitivity to subjective contours was independent of the support ratio, unlike that of older children and adults. The results suggest that, during middle childhood, the interpolation of subjective contours becomes tied to the support ratio, so that contours that are more likely to reflect the contours of real objects (i.e., highly supported contours) are more easily interpolated.

Visual cognitive function: changes associated with chronic insomnia in older adults

Older adults typically exhibit poor sleep efficiency as well as a decline in visual perception. In this study, the authors investigated whether late-life insomnia is associated with age-related changes in visual processing of global and local aspects of hierarchical figures. The study findings suggest that late-life insomnia may be one of the most important factors contributing to the decline of visual processing in older adults. The findings offer hope that treatment of insomnia in older adults could have beneficial effects on improving visual processing in this population.

Developmental trends in utilizing perceptual closure for grouping of shape: effects of spatial proximity and collinearity

In two experiments, visual search was used to study the grouping of shape on the basis of perceptual closure among participants 5-23 years of age. We first showed that young children, like adults, demonstrate an efficient search for a concave target among convex distractors for closed connected stimuli but an inefficient search for open stimuli. Reliable developmental differences, however, were observed in search for fragmented stimuli as a function of spatial proximity and collinearity between the closure-inducing fragments. When only closure was available, search for all the age groups was equally efficient for spatially close fragments and equally inefficient for spatially distant fragments. When closure and collinearity were available, search for spatially close fragments was equally efficient for all the age groups, but search for spatially distant fragments was inefficient for younger children and improved significantly between ages 5 and 10. These findings suggest that young children can utilize closure as efficiently as can adults for the grouping of shape for closed or nearly closed stimuli. When the closure-inducing fragments are spatially distant, only older children and adults, but not 5-year-olds, can utilize collinearity to enhance closure for the perceptual grouping of shape.

Influence of past experience on perceptual grouping

We used primed matching to examine the microgenesis of perceptual organization for familiar (upright letters) and unfamiliar (inverted letters) visual configurations that varied in the connectedness between their line components. The configurations of upright letters were available for priming as early as 40 ms, irrespective of connectedness between their line components. The configurations of connected inverted-letter primes were also available this early, but the configurations of disconnected inverted letters were not available until later These results show that past experience contributes to the early grouping of disconnected line segments into configurations. These findings suggest an interactive model of perceptual organization in which both image-based properties (e.g., connectedness) and input from object memories contribute to perceptual organization.