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Predictive coding theories of autism suggest that symptoms could result from an atypical learning of expectations. We assessed whether adults with autism could learn expectations in an uncertain context. Twenty-nine neurotypicals and 25 autistic adults participated in an associative learning task. After hearing a tone, participants had to predict the rotation direction of a dot pair, and to report what they perceived. There was a probabilistic association between the tone and the rotation direction. This association could reverse within a block. Both groups were biased by their expectations, as they reported perceiving a rotation consistent with the contingency in a subset of ambiguous trials where the dots did not rotate. Participants made predictions above chance level, but contrary to neurotypicals, autistic participants updated their prior expectation less after a change in contingency. Computational modeling revealed a smaller influence of associative learning on perceptual expectations in the autism group. In an additional task, participants reported how confident they were about their percepts. Both groups expressed confidence in relation to the stimuli, but certainty ratings reflected response times in neurotypical participants only. These findings, showing a more inflexible adjustment of priors in autism, should help refining the predictive coding hypotheses of autism.

Colour and space are pervasive topics in both perception and art. This article investigates the role of colour and pattern in relation to space and time in the art works by two artists: Frank Stella, a well-known Post-War American abstract painter, and Pieter Vermeersch, an emerging Belgian abstract painter, representing a contemporary trend to break the barriers between artistic disciplines. While Stella adheres to the Modernist logic of non-illusionistic, non-spatial, non-referential art as object, perceived instantaneously, Vermeersch explores ways to enhance the viewers’ spatial and temporal experiences through complex art installations with multiple objects and architectural elements interacting with each other and with the spaces in which they are embedded. We discuss these major themes in some representative art works, and in the way they are perceived and appreciated by contemporary viewers, investigated in four empirical studies: two laboratory experiments using well-controlled stimuli derived from at works, and two museum studies employing a variety of methods, including mobile eye-tracking and questionnaires.

Do aesthetic preferences for images of neatly organized compositions (e.g., images collected on blogs like Things Organized Neatly©) generalize across cultures? In an earlier study, focusing on stimulus and personal properties related to order and complexity, Western participants indicated their preference for one of two simultaneously presented images (100 pairs). In the current study, we compared the data of the native Dutch-speaking participants from this earlier sample (N = 356) to newly collected data from a native Chinese-speaking sample (N = 220). Overall, aesthetic preferences were quite similar across cultures. When relating preferences for each sample to ratings of order, complexity, soothingness, and fascination collected from a Western, mainly Dutch-speaking sample, the results hint at a cross-culturally consistent preference for images that Western participants rate as more ordered, but a cross-culturally diverse relation between preferences and complexity. [ABSTRACT FROM AUTHOR]

The purpose of the present note is to draw attention to the potential role of a recently discovered visual illusion in creating traffic accidents. The illusion consists in a compelling and immediate experience that the space behind an occluding object in the foreground is empty. Although the illusion refers to a region of space, which is invisible due to occlusion (a blind spot), there is evidence to suggest that it is nevertheless driven by visual mechanisms and that it can be just as deceptive and powerful as ordinary visual illusions. We suggest that this novel illusion can make situations involving blind spots in a road user's field of view even more dangerous than one would expect based on the lack of visibility by itself. This could be because it erroneously makes the road user feel that (s)he has actually seen everything there is to see, and thus has verified that the blind spot is empty. This hypothesis requires further testing before definitive conclusions can be drawn, but we wish to make researchers and authorities involved in the analysis of traffic accidents and on-the-spot crash investigations aware of its potential role in order to encourage registration of relevant data and facilitate further research.

Visual perception in individuals with autism spectrum disorder (ASD) is often debated in terms of enhanced local and impaired global perception. Deficits in global motion perception seem to support this characterization, although the evidence is inconsistent. We conducted a large meta-analysis on global motion, combining 48 articles on biological and coherent motion. Results provide evidence for a small global motion processing deficit in individuals with ASD compared to controls in both biological and coherent motion. This deficit appears to be present independent of the paradigm, task, dependent variable, age or IQ of the groups. Results indicate that individuals with ASD are less sensitive to these types of global motion, although the difference in neural mechanisms underlying this behavioral difference remains unclear.

Aesthetic experiences with photographs are common in our digital society, yet there are many gaps in our scientific knowledge about how we look at, and aesthetically appreciate, photographs. Specifically, an in-depth view of these aesthetic experiences that takes into account the nuances of the photograph, as well as the emotional and meaning-making processes in the viewer, is lacking. In this project, we focus on a varied set of 58 contemporary artistic photographs (selected by expert judges) and, in two complementary studies, examine how 259 nonexperts aesthetically experience these photographs, whether contextual changes can impact their aesthetic preferences, and whether participants' preferences relate to their emotional responses and how they were making meaning of the photographs. In general, participants' aesthetic experiences varied greatly between photographs but they were robust against contextual changes (of other photographs or theme information). Emotional experience played a key role in participants' preferences, with low preferences for photographs associated with negative emotions (e.g., blood, sickness, and pollution), and high preferences for photographs associated with positive emotions (e.g., nature and a street scene reminiscent of vacation). Making meaning of (what was in) the photograph was also important, and participants' answers suggest that they did not always fully understand the photographs or integrate the photographs' nuances into a coherent whole. Results have implications for empirical aesthetics, the (art) photography practice, and how we are responding to photographs in general. [ABSTRACT FROM AUTHOR]

Pictorial awareness is addressed through experimental phenomenology involving over 90 naïve participants. Since one can't look at the "same" picture twice the study uses one-shot trials. The participant's fascination for the duration of a session is held through the artistic principle of theme and variation. Six variations focus on the theme of pictorial geometry, both two-dimensional and three-dimensional. Major findings are: Idiosyncratic deviations from veridical are huge as compared to common textbook "effects." Observers wield arbitrary heuristics for tasks that are "formally related." The assumption of a common formal framework is apparently unsound. The notion of "inverse optics" is misleading. A fair fraction of the population appears to lack monocular stereopsis as intuitive awareness. It suggests an as-yet unrecognized, but perhaps common variety of aphantasia. [ABSTRACT FROM AUTHOR]

Previous research suggested that adolescents with autism spectrum disorder are better than typically developing children in detecting local, non-social details within complex visual scenes. To better understand these differences, we used the image database by Sareen et al., containing the size and on-screen location information of all changes in the images, in a change blindness paradigm. In this task, an original and a modified real-world scene, separated by a gray blank, alternate repeatedly until observers detect the change. Our results indicated that participants with and without autism spectrum disorder performed similarly when scenes were presented upright, but that only the performance of the typically developing adolescents became worse in the inverted scene condition. In this condition, the correlation between performance and both image difficulty and change predictability was significantly weaker in autism spectrum disorder than in typically developing participants. We suggest that these findings result from a more locally biased search strategy in people with autism spectrum disorder, compared to typically developing participants, in tasks in which the rapid processing of global information does not help to improve change detection performance. Finally, although we found change location, change size, and age to influence participant performance, none of these was directly linked to the observed group-level differences.

Since its initial development, the embedded figures test (EFT) has been used extensively to measure local-global perceptual style. However, little is known about the perceptual factors that influence target detection. The current study aimed to investigate "disembedding" in children with and without ASD, aged 8-15 years, using the newly developed, stimulus-controlled L-EFT, M-EFT and D-EFT. Firstly, results revealed superior disembedding for children with ASD, irrespective of the type of target or embedding context, although the ASD group took more time in both the M-EFT and D-EFT. Secondly, the number of target lines continuing into the context proved more of a hindrance for the controls. Taken together, these findings provide strong evidence to support the notion of superior disembedding in ASD.

Local and global visual processing abilities and processing style were investigated in individuals with autism spectrum disorder (ASD) versus typically developing individuals, children versus adolescents and boys versus girls. Individuals with ASD displayed more attention to detail in daily life, while laboratory tasks showed slightly reduced global processing abilities, intact local processing abilities, and a more locally oriented processing style. However, the presence of these group differences depended on particular task and sample (i.e., age and gender) characteristics. Most measures of local and global processing did not correlate with each other and were not associated with processing style. Significant associations between local-global processing and ASD symptom severity were observed, but the causality of these associations remains unclear.

The multiple object tracking (MOT) paradigm has proven its value in targeting a number of aspects of visual cognition. This study used MOT to investigate the effect of object-based grouping, both in children with and without autism spectrum disorder (ASD). A modified MOT task was administered to both groups, who had to track and distinguish four targets that moved randomly amongst four distracters, irrespective of the grouping condition. No group difference was revealed between children with and without ASD: both showed adequate MOT abilities and a similar amount of grouping interference. Implications of the current result are considered for previous MOT studies, the developmental trajectory of perceptual grouping, and the idea of heightened sensitivity to task characteristics in ASD.

While most typically developing (TD) participants have a coarse-to-fine processing style, people with autism spectrum disorder (ASD) seem to be less globally and more locally biased when processing visual information. The stimulus-specific spatial frequency content might be directly relevant to determine this temporal hierarchy of visual information processing in people with and without ASD. We implemented a semantic priming task in which (in)congruent coarse and/or fine spatial information preceded target categorization. Our results indicated that adolescents with ASD made more categorization errors than TD adolescents and needed more time to process the prime stimuli. Simultaneously, however, our findings argued for a processing advantage in ASD, when the prime stimulus contains detailed spatial information and presentation time permits explicit visual processing.

Studies using hierarchical patterns to test global precedence and local-global interference in individuals with ASD have produced mixed results. The current study focused on stimulus variability and locational uncertainty, while using different attentional modes. Two groups of 44 children with and without ASD completed a divided attention task as well as a global and local selective attention task. The results revealed global-to-local and local-to-global interference in ASD, to the same extent as in the TD group. Both groups struggled with the same type of stimuli (i.e., ignoring the global level information) and performed similar in all three tasks. Future studies on (visual) information processing in ASD should pursue the impact of stimulus noise and trial-by-trial uncertainty further.

Adolescents with and without autism spectrum disorder (ASD) performed two priming experiments in which they implicitly processed a prime stimulus, containing high and/or low spatial frequency information, and then explicitly categorized a target face either as male/female (gender task) or as positive/negative (Valence task). Adolescents with ASD made more categorization errors than typically developing adolescents. They also showed an age-dependent improvement in categorization speed and had more difficulties with categorizing facial expressions than gender. However, in neither of the categorization tasks, we found group differences in the processing of coarse versus fine prime information. This contradicted our expectations, and indicated that the perceptual differences between adolescents with and without ASD critically depended on the processing time available for the primes.

The allure of aesthetic appeal in images captivates our senses, yet the underlying intricacies of aesthetic preferences remain elusive. In this study, we pioneer a novel perspective by utilizing several different machine learning (ML) models that focus on aesthetic attributes known to influence preferences. Our models process these attributes as inputs to predict the aesthetic scores of images. Moreover, to delve deeper and obtain interpretable explanations regarding the factors driving aesthetic preferences, we utilize the popular Explainable AI (XAI) technique known as SHapley Additive exPlanations (SHAP). Our methodology compares the performance of various ML models, including Random Forest, XGBoost, Support Vector Regression, and Multilayer Perceptron, in accurately predicting aesthetic scores, and consistently observing results in conjunction with SHAP. We conduct experiments on three image aesthetic benchmarks, namely Aesthetics with Attributes Database (AADB), Explainable Visual Aesthetics (EVA), and Personalized image Aesthetics database with Rich Attributes (PARA), providing insights into the roles of attributes and their interactions. Finally, our study presents ML models for aesthetics research, alongside the introduction of XAI. Our aim is to shed light on the complex nature of aesthetic preferences in images through ML and to provide a deeper understanding of the attributes that influence aesthetic judgements. [ABSTRACT FROM AUTHOR]

The mechanisms underlying atypical sensory processing in autism remain to be elucidated, but research points toward a role of the glutamatergic/GABAergic balance. To investigate the potential relationships between visual sensitivity and its molecular correlates in autism, we combined data from electroencephalography (EEG) and magnetic resonance spectroscopy (MRS) studies. Twenty autistic adults and sixteen neurotypical adults (NT) participated in both an EEG study assessing visual sensitivity (Sapey‐Triomphe et al., Autism Research, 2023) and in an MRS study measuring Glx and GABA+ concentrations in the occipital cortex (Sapey‐Triomphe et al., Molecular Autism, 2021). These studies revealed no group differences in neural detection thresholds or in Glx/GABA levels in the occipital cortex. Neural detection thresholds for contrast and spatial frequency (SF) were determined using fast periodic visual stimulations and neural frequency tagging. In the present study, Glx/GABA+ concentrations in the occipital cortex and neural detection thresholds did not differ between groups. Interestingly, lower Glx/GABA+ ratios were associated with lower contrast detection thresholds and higher SF detection thresholds. These correlations were also significant within the neurotypical and autistic groups. This report suggests that the Glx/GABA balance regulates visual detection thresholds across individuals. In both autistic and NTs, lower Glx/GABA ratios in the occipital cortex allow for better detection of visual inputs at the neural level. This study sheds light on the neurochemical underpinnings of visual sensitivity in autism and warrants further investigation. Lay Summary: Visual sensitivity is atypical in autism, but its underlying neural and molecular mechanisms remain relatively unknown. Here, we demonstrate a relationship between the brain's ability to detect a visual information and the concentrations of two key neurotransmitters. Interestingly, this relationship was observed in both neurotypical and autistic adults, suggesting an overall intact role of these neurotransmitters in processing low‐level visual information in autism. [ABSTRACT FROM AUTHOR]

Categorization is an essential cognitive and perceptual process, which happens spontaneously. However, earlier research often neglected the spontaneous nature of this process by mainly adopting explicit tasks in behavioral or neuroimaging paradigms. Here, we use frequency-tagging (FT) during electroencephalography (EEG) in 22 healthy human participants (both male and female) as a direct approach to pinpoint spontaneous visual categorical processing. Starting from schematic natural visual stimuli, we created morph sequences comprising 11 equal steps. Mirroring a behavioral categorical perception discrimination paradigm, we administered a FT-EEG oddball paradigm, assessing neural sensitivity for equally sized differences within and between stimulus categories. Likewise, mirroring a behavioral category classification paradigm, we administered a sweep FT-EEG oddball paradigm, sweeping from one end of the morph sequence to the other, thereby allowing us to objectively pinpoint the neural category boundary. We found that FT-EEG can implicitly measure categorical processing and discrimination. More specifically, we could derive an objective neural index of the required level to differentiate between the two categories, and this neural index showed the typical marker of categorical perception (i.e., stronger discrimination across as compared with within categories). The neural findings of the implicit paradigms were also validated using an explicit behavioral task. These results provide evidence that FT-EEG can be used as an objective tool to measure discrimination and categorization and that the human brain inherently and spontaneously (without any conscious or decisional processes) uses higher-level meaningful categorization information to interpret ambiguous (morph) shapes. [ABSTRACT FROM AUTHOR]

In order to accurately study in situ aesthetic responses as participants explore gallery spaces and museum exhibitions, we need a way to comprehensively, exhaustively, and precisely classify the behaviors displayed in such settings. We have restructured and extended a preliminary taxonomy of museum navigation behavior to give it a hierarchical structure and precise behavioral criteria. Our taxonomy features categories for both art related and non-art related eye-gaze behaviors. Art Gazes are further categorized as Orientation behaviors, which do not require bodily movement, or Changing Perspective behaviors, which do require bodily movement. This taxonomy, consisting of 32 different behaviors, was developed using mobile eye-tracking data collected with Tobii glasses at the Pieter Vermeersch exhibition at the M Museum in Leuven. The four-room exhibition featured contemporary artworks primarily consisting of marble slabs painted with color gradients, as well as large, architectural installation features. Three raters coded the mobile eye-tracking recordings according to the taxonomical criteria. Four participants' gaze data were used to assess interrater reliability, using the correlation between the durations of taxonomical behaviors coded for each participant by each rater (r =.98) and Cohen's kappa for the agreed number of instances of taxonomical behaviors (k =.67). The taxonomy is both comprehensive and exhaustive in capturing the array of behaviors displayed by participants in the exposition. The use of this taxonomy, or increasingly refined versions of it, will enable us to assess specific behavioral processes which occur in naturalistic museum settings and which may influence aesthetic appreciation. [ABSTRACT FROM AUTHOR]