Size Judgments Research Articles

Mechanical properties and mechanism of damage and deterioration of coal under cyclic loading

To analyze the mechanical characteristics of damaged coal bodies and the mechanisms of evolution and degradation of internal pore and fracture defects under cyclic loads, raw coal containing original pore and fracture materials was selected as the research material. This study investigates the impact of cyclic loading on the mechanical properties of damaged coal and the evolution of flaw structures, such as pores and cracks, within the coal. A micro-fracture size judgment index (Ci) was defined based on fracture volume to determine the dominant macroscopic failure mode in coal bodies. The results indicate that a “hysteresis loop” forms in the loading and unloading curves of each cycle due to cyclic loading. During the cyclic loading and unloading phase, both the loading elastic modulus and the damage parameters of coal samples increase proportionally with the level of loading and the number of cycles. In the constant amplitude cyclic loading and unloading phase, there is minimal variation in the loading elastic modulus and damage parameters of coal samples, indicating their stability. As micro-scale fractures evolve within the coal body, pores with a volume less than 109 μm3 decrease with increasing cyclic loading and unloading during amplification cycles but remain relatively stable during equal amplitude cyclic loading phases. The contribution rate of damage to fractures with a volume between 109 and 1011 μm3 increases with higher load levels and cyclic loading/unloading during both amplification and equal amplitude cycles. The minimum order of magnitude for fracture volume that dominates macroscopic failure in the coal body is determined to be 109 and 1010 μm3.

Determinants of child body weight categorization in parents and health care professionals: Anexperimental study.

Parents infrequently recognize childhood overweight/obesity and healthcare professionals (HCPs) also struggle to visually identify it, potentially limiting the offer and uptake of weight management support. This study examined perceptual and attitudinal/cognitive determinants of child weight judgements amongst parents and HCPs to identify targets for intervention. We used a mixed experimental design with parents and HCPs as the between-participants factor. Stimulus gender, age and BMI centile were the within-participant repeated measures factors. One hundred and fifty-six HCPs and 249 parents of children aged 4-5 or 10-11 years viewed simulated child images. They estimated their relative size and categorized the weight status of each figure. Stimuli were photo-realistic figural scales based on 3D-scans of 4- to 5- and 10- to 11-year-old children varying in adiposity. Participants also reported their beliefs about causes, controllability and categorization of child weight. Both groups accurately estimated the figures' relative size. However, categorization of higher weight figures was poor, demonstrating a mismatch between perceptual judgements of size and categorization of weight status. Lower levels of comfort with assigning 'overweight' categorizations to children, and a stronger belief that weight was controllable by the child/parent, predicted less accurate weight status categorizations. Parental and HCP misperceptions when categorizing children's higher weight are related to attitudinal/cognitive factors, including reluctance to label a child's weight status as overweight and beliefs about whether a child's weight can be controlled by them or their family.

The influence of body orientation on length judgements.

Perceiving the size of a visual object requires the combination of various sources of visual information. A recent paper by Kim et al. (Body Orientation Affects the Perceived Size of Objects. Perception 2022, 51: 25-36) concluded that body orientation played a substantial role. The present paper aims to answer the question of whether the reported effect of body orientation on visuo-haptic size matching was due to effects on the visual or the haptic judgements of size. To do so, we used a within-participant design combining an experiment using visuo-haptic size matching with two experiments that assessed the visual and haptic size-percept using free magnitude estimation. Our experiments produced a systematic visuo-haptic mismatch, but the sign of the mismatch was opposite to that of the original study. Moreover, our study did not reveal a systematic effect of body orientation on this mismatch. Thirdly, we found that the mismatch we determined from participants matching a visual and haptic percept was considerably smaller than the mismatch we derived from their visual and haptic size estimates. In summary, our results emphasise that conclusions about the perceived size of objects are very sensitive to details of the experimental approach.

Features are more than just filling in the blanks on body size scales

ABSTRACT Despite widespread misperceptions of body size and shape, the specific visual features influencing such judgments remain unclear. This study assessed the contribution of internal body features (e.g., colour, shading) to the accuracy of female body size judgements and whether that contribution varies with body size. Using a bodyline task, 100 female participants evaluated images of female bodies, either depicted as real bodies including internal features (feature stimuli) or images of bodies as silhouettes only (silhouette stimuli). The results showed greater overall errors in body size estimation for silhouettes compared to full feature images. However, the direction of error differed for large and small bodies: small silhouettes were judged larger than their full-feature counterparts, while large silhouettes were judged smaller. These findings emphasize the importance of internal body features in shaping perceptions of female body size and highlight the complexity of judgement accuracy across different body sizes.

The effect of retinal sizes on ensemble size judgments of objects in different depth planes

The effect of retinal sizes on ensemble size judgments of objects in different depth planes

Testing the validity of online psychophysical measurement of body image perception.

This body image study tests the viability of transferring a complex psychophysical paradigm from a controlled in-person laboratory task to an online environment. 172 female participants made online judgements about their own body size when viewing images of computer-generated female bodies presented in either in front-view or at 45-degrees in a method of adjustment (MOA) paradigm. The results of these judgements were then compared to the results of two laboratory-based studies (with 96 and 40 female participants respectively) to establish three key findings. Firstly, the results show that the accuracy of online and in-lab estimates of body size are comparable, secondly that the same patterns of visual biases in judgements are shown both in-lab and online, and thirdly online data shows the same view-orientation advantage in accuracy in body size judgements as the laboratory studies. Thus, this study suggests that that online sampling potentially represents a rapid and accurate way of collecting reliable complex behavioural and perceptual data from a more diverse range of participants than is normally sampled in laboratory-based studies. It also offers the potential for designing stratified sampling strategies to construct a truly representative sample of a target population.

Breadth of substance use is associated with the selection of a larger food portion size via elevated impulsivity

Substance use is associated with altered or elevated food consumption and disordered eating. In the present study we examined whether breadth (variety) of drug use was associated with elevated portion size in a general population sample as it was in persons in recovery from substance use disorder. Furthermore, measures of emotional eating, impulsivity, food misuse, food craving were taken as possible mediators and reward responsiveness was examined as a potential moderator of this association. 444 adults (48.6 % women, mean age of 47.8 years) completed an online study in which they were asked to make judgements of ideal portion size for 6 different foods using a validated online tool that allowed participants to adjust the portion size of images of foods. Ideal portion size has been identified as a strong predictor of actual consumption. Participants were also asked to report the number of substances used in the past and provide anthropometric information. The results confirmed that breadth of drug use was associated with selection of higher portion size. Reward responsiveness was not a moderator of this relationship. Of the tested mediators, only impulsivity mediated the association between breadth of drug use and portion size. The results show that impulsivity may underlie the association between eating and substance use.

Reduced influence of perceptual context in mild traumatic brain injury is not an illusion.

Perceptual grouping is impaired following mild traumatic brain injury (mTBI). This may affect visual size perception, a process influenced by perceptual grouping abilities. We conducted two experiments to evaluate visual size perception in people with self-reported history of mTBI, using two different size-contrast illusions: the Ebbinghaus Illusion (Experiment 1) and the Müller-Lyer illusion (Experiment 2). In Experiment 1, individuals with mTBI and healthy controls were asked to compare the size of two target circles that were either the same size or different sizes. The target circles appeared by themselves (no-context condition), or were surrounded by smaller or larger circles (context condition). Similar levels of accuracy were evident between the groups in the no-context condition. However, size judgements by mTBI participants were more accurate in the context condition, suggesting that they processed the target circles separately from the surrounding circles. In Experiment 2, individuals with mTBI and healthy controls judged the length of parallel lines that appeared with arrowheads (context condition) or without arrowheads (no context condition). Consistent with Experiment 1, size judgements by mTBI participants were more accurate than size judgements by control participants in the context condition. These findings suggest that mTBI influences size perception by impairing perceptual grouping of visual stimuli in near proximity.

Predicting Online Behavioural Responses to Transcranial Direct Current Stimulation in Stroke Patients with Anomia.

Anomia, or difficulty naming common objects, is the most common, acquired impairment of language. Effective therapeutic interventions for anomia typically involve massed practice at high doses. This requires significant investment from patients and therapists. Aphasia researchers have increasingly looked to neurostimulation to accelerate these treatment effects, but the evidence behind this intervention is sparse and inconsistent. Here, we hypothesised that group-level neurostimulation effects might belie a more systematic structure at the individual level. We sought to test the hypothesis by attempting to predict the immediate (online), individual-level behavioural effects of anodal and sham neurostimulation in 36 chronic patients with anomia, performing naming and size judgement tasks. Using clinical, (pre-stimulation) behavioural and MRI data, as well as Partial Least Squares regression, we attempted to predict neurostimulation effects on accuracies and reaction times of both tasks. Model performance was assessed via cross-validation. Predictive performances were compared to that of a null model, which predicted the mean neurostimulation effects for all patients. Models derived from pre-stimulation data consistently outperformed the null model when predicting neurostimulation effects on both tasks' performance. Notably, we could predict behavioural declines just as well as improvements. In conclusion, inter-patient variation in online responses to neurostimulation is, to some extent, systematic and predictable. Since declines in performance were just as predictable as improvements, the behavioural effects of neurostimulation in patients with anomia are unlikely to be driven by placebo effects. However, the online effect of the intervention appears to be as likely to interfere with task performance as to improve it.

Application of 3D Printing Technology in Customized Garment Production

Abstract In this paper, human body images are acquired by DSLR camera shooting, and the photos are grayscaled based on the HIS model. Then, the different operations weaken the similar parts between the images, and the other parts of the photos are highlighted. The image is separated from the background by image binarization. After the contour detection of the image, the pixel coordinates of the contour points in the image are deposited into a dynamic array by the size judgment of the pixel values. The subsequent size calculation is called to make a pad. According to the human body, clothing size automation measurement has been derived from the human body characteristics of the size, the use of three-dimensional printing technology to produce clothing to meet consumer demand, and three-dimensional printing technology to support the production of customized clothing under the experimental analysis. It is verified that the data difference between the actual size of the subject’s ready-made clothes and the size of the clothes produced based on 3D printing technology is kept within ±0.48cm. The virtual fitting pressure is less than the comfort threshold of women’s upper body pressure (2.75kpa), which indicates that the clothes produced by this research will not cause physiological discomfort to the human body and, at the same time, meet the consumer’s personalized clothing customization needs.

Humans' (Homo sapiens), capuchin monkeys' (Sapajus [Cebus] apella), and rhesus macaques' (Macaca mulatta) size judgments shift when stimuli change in frequency.

When making decisions, humans often strive to uphold objective, absolute standards, such as about what is small versus large, blue versus purple, or unfair versus fair, suggesting that our judgments should not be swayed by extraneous factors such as the sequence or frequency of events to be judged. Yet in previous research, when some items (e.g., threatening faces) became less frequent, humans responded by expanding their concept (of "threatening") to include more ambiguous stimuli. We assessed the origins of this perceptual frequency bias by testing 25 capuchins, seven rhesus monkeys, and 102 humans on a computer task in which they had to classify one circle at a time (pulled from a continuum of 50 circle sizes) as either small or large. Small and large circles initially appeared with equal probability but over time small circles either became less frequent, more frequent, or did not change in frequency. All three species showed changes in judgment, but contrary to predictions, they contracted, rather than expanded, their size judgments of the less frequent category. In other words, when small circles became rare, participants were more likely to judge ambiguous circles sizes as large (and vice versa). This may have been due to the immediate explicit feedback, as has recently been found in humans, and we consider possible mechanisms driving our participants' responses. These results suggest that humans' difficulties in maintaining absolute standards are shared with other animals. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Right frontal HD-tDCS reveals causal involvement of time perception networks in temporal processing of concepts

Evidence suggests that perceptual and action related features of concepts are grounded in the corresponding sensory-motor networks in the human brain. However, less is known about temporal features of event concepts (e.g., a lecture) and whether they are grounded in time perception networks. We examined this question by stimulating the right dorsolateral prefrontal cortex (rDLPFC)—a part of time perception network—using HD-tDCS and subsequently recording EEG while participants performed semantic and time perception tasks. Semantic tasks were composed of event noun duration judgment (EDur), object noun size judgement (OSize), event (EVal) and object noun valence judgement. In the time perception task, participants judged the durations of pure tones. Results showed that cathodal stimulation accelerated responses for time perception task and decreased the magnitude of global field power (GFP) compared to sham stimulation. Semantic tasks results revealed that cathodal, but not sham, stimulation significantly decreased GFP for EDur relative to OSize, and to EVal. These findings provide first causal evidence that temporal features of event words are grounded in the rDLPFC as part of the temporal cognition network and shed light on the conceptual processing of time.

Differential involvement of the anterior and posterior hippocampus, parahippocampus, and retrosplenial cortex in making precise judgments of spatial distance and object size for remotely acquired memories of environments and objects.

The hippocampus is known to support processing of precise spatial information in recently learned environments. It is less clear, but crucial for theories of systems consolidation, to know whether it also supports processing of precise spatial information in familiar environments learned long ago and whether such precision extends to objects and numbers. In this fMRI study, we asked participants to make progressively more refined spatial distance judgments among well-known Toronto landmarks (whether landmark A is closer to landmark B or C) to examine hippocampal involvement. We also tested whether the hippocampus was similarly engaged in estimating magnitude regarding sizes of familiar animals and numbers. We found that the hippocampus was only engaged in spatial judgment. Activation was greater and lasted longer in the posterior than anterior hippocampus, which instead showed greater modulation as discrimination between spatial distances became more fine grained. These findings suggest that the anterior and posterior hippocampus have different functions which are influenced differently by estimation of differential distance. Similarly, parahippocampal-place-area and retrosplenial cortex were involved only in the spatial condition. By contrast, activation of the intraparietal sulcus was modulated by precision in all conditions. Therefore, our study supports the idea that the hippocampus and related structures are implicated in retrieving and operating even on remote spatial memories whenever precision is required, as posted by some theories of systems consolidation.

Monocular cues are superior to binocular cues for size perception when they are in conflict in virtual reality

Three-dimensional (3D) depth information is important to estimate object sizes. The visual system extracts 3D depth information using both binocular cues and monocular cues. However, how these different depth signals interact with each other to compute the object size in 3D space is unclear. Here, we aim to study the relative contribution of monocular and binocular depth information to size perception in a modified Ponzo context by manipulating their relations in a virtual reality environment. Specifically, we compared the amount of the size illusion in the following two conditions, in which monocular cues and binocular disparity in the Ponzo context can indicate the same depth sign (congruent) or opposite depth sign (incongruent). Our results show an increase in the amount of the Ponzo illusion in the congruent condition. In contrast, in the incongruent condition, we find that the two cues indicating the opposite depth signs do not cancel out the Ponzo illusion, suggesting that the effects of the two cues are not equal. Rather, binocular disparity information seems to be suppressed and the size judgment is mainly dependent on the monocular depth information when the two cues are in conflict. Our results suggest that monocular and binocular depth signals are fused for size perception only when they both indicate the same depth sign and top-down 3D depth information based on monocular cues contributes more to size perception than binocular disparity when they are in conflict in virtual reality.

Sizing up the crowd: Assessing spatial integration difficulties in body size judgements across eating disorder symptomatology.

Body size judgements are frequently biased, or inaccurate, and these errors are further exaggerated for individuals with eating disorders. Within the eating disorder literature, it has been suggested that exaggerated errors in body size judgements are due to difficulties with integration. Across two experiments, we developed a novel integration task, named the Ebbinghaus Illusion for Bodies in Virtual Reality (VR), to assess whether nearby bodies influence the perceived size of a single body. VR was used to simulate the appearance of a small crowd around a central target body. In Experiment 1 (N = 412), participants were required to judge the size of a central female target within a crowd. Experiment 1 revealed an Ebbinghaus Illusion, in which a central female appeared larger when surrounded by small distractors, but comparatively smaller when surrounded by large distractors. In other words, the findings of Experiment 1 demonstrate that surrounding crowd information is integrated when judging an individual's body size; a novel measure of spatial integration (i.e., an Ebbinghaus Illusion for Bodies in VR). In Experiment 2 (N = 96), female participants were selected based on high (n = 43) and low (n = 53) eating disorder symptomatology. We examined whether the magnitude of this illusion would differ amongst those with elevated versus low eating disorder symptomatology, in accordance with weak central coherence theory, with the high symptomatology group displaying less spatial integration relative to the low group. The results of Experiment 2 similarly found an Ebbinghaus Illusion for Bodies in VR. However, illusion magnitude did not vary across high and low symptomatology groups. Overall, these findings demonstrate that surrounding crowd information is integrated when judging individual body size; however, those with elevated eating disorder symptomatology did not show any integration deficit on this broader measure of spatial integration.

Temporal features of concepts are grounded in time perception neural networks: An EEG study

Experimental evidence suggests that modality-specific concept features such as action, motion, and sound partially rely on corresponding action/perception neural networks in the human brain.Little is known, however, about time-related features of concepts. We examined whether temporal features of concepts recruit networks that subserve time perception in the brain in an EEG study using event and object nouns. Results showed significantly larger ERPs for event duration vs object size judgments over right parietal electrodes, a region associated with temporal processing. Additionally, alpha/beta (10–15 Hz) neural oscillation showed a stronger desynchronization for event duration compared to object size in the right parietal electrodes. This difference was not seen in control tasks comparing event vs object valence, suggesting that it is not likely to reflect a general difference between event and object nouns. These results indicate that temporal features of words may be subserved by time perception circuits in the human brain.

Looking at the Ebbinghaus illusion: differences in neurocomputational requirements, not gaze-mediated attention, explain a classic perception-action dissociation.

Perceiving and grasping an object present an animal with different sets of computational problems. The solution in primates entails the specialization of separate neural networks for visual processing with different object representations. This explains why the Ebbinghaus illusion minimally affects the grasping hand's in-flight aperture, which normally scales with target size, even though the size of the target disc remains misperceived. An attractive alternative account, however, posits that grasps are refractory to the illusion because participants fixate on the target and fail to attend to the surrounding context. To test this account, we tracked both limb and gaze while participants made forced-choice judgments of relative disc size in the Ebbinghaus illusion or did so in combination with grasping or manually estimating the size of one of the discs. We replicated the classic dissociation: grasp aperture was refractory to the measured illusory effect on perceived size, while judgments and manual estimates of disc size were not. Importantly, the number of display-wide saccades per second and the percentage of total fixation time or fixations directed at the selected disc failed to explain the dissociation. Our findings support the contention that object perception and goal-directed action rely on distinct visual representations. This article is part of a discussion meeting issue 'New approaches to 3D vision'.

Hand constraint reduces brain activity and affects the speed of verbal responses on semantic tasks

According to the theory of embodied cognition, semantic processing is closely coupled with body movements. For example, constraining hand movements inhibits memory for objects that can be manipulated with the hands. However, it has not been confirmed whether body constraint reduces brain activity related to semantics. We measured the effect of hand constraint on semantic processing in the parietal lobe using functional near-infrared spectroscopy. A pair of words representing the names of hand-manipulable (e.g., cup or pencil) or nonmanipulable (e.g., windmill or fountain) objects were presented, and participants were asked to identify which object was larger. The reaction time (RT) in the judgment task and the activation of the left intraparietal sulcus (LIPS) and left inferior parietal lobule (LIPL), including the supramarginal gyrus and angular gyrus, were analyzed. We found that constraint of hand movement suppressed brain activity in the LIPS toward hand-manipulable objects and affected RT in the size judgment task. These results indicate that body constraint reduces the activity of brain regions involved in semantics. Hand constraint might inhibit motor simulation, which, in turn, would inhibit body-related semantic processing.

View Normalization of Object Size in the Right Parietal Cortex.

Prior knowledge alters perception already on early levels of processing. For instance, judging the display size of an object is affected by its familiar size. Using functional magnetic resonance imaging, we investigated the neural processes involved in resolving ambiguities between familiar object size and physical object size in 33 healthy human subjects. The familiar size was either small or large, and the object was displayed as either small or large. Thus, the size of the displayed object was either congruent or incongruent with its internally stored canonical size representation. Subjects were asked to indicate where the stimuli appeared on the screen as quickly and accurately as possible, thereby ensuring that differential activations cannot be ascribed to explicit object size judgments. Incongruent (relative to congruent) object displays were associated with enhanced activation of the right intraparietal sulcus (IPS). These data are consistent with but extend previous patient studies, which found the right parietal cortex involved in matching visual objects presented atypically to prototypical object representations, suggesting that the right IPS supports view normalization of objects. In a second experiment, using a parametric design, a region-of-interest analysis supported this notion by showing that increases in size mismatch between the displayed size of an object and its familiar viewing size were associated with an increased right IPS activation. We conclude that the right IPS performs view normalization of mismatched information about the internally stored prototypical size and the current viewing size of an object.

Exploring the development of high-level contributions to body representation using the rubber hand illusion and the monkey hand illusion

During development our body undergoes significant changes, yet we are able to maintain a coherent experience of our body and sense of self. Bodily experience is thought to comprise integration of multisensory signals (vision, touch, and proprioception) constrained by top-down knowledge of body appearance. Evidence from developmental studies suggests that low-level multisensory integration develops throughout childhood, reaching adult levels by 10 years of age. However, how high-level cognitive knowledge changes during childhood to constrain our multisensory body experience is unknown. This study describes four experiments examining high-level contributions to the bodily experience in children compared with adults using the rubber hand illusion and a monkey hand illusion. We found that children (5–17 years of age) exhibited more flexible body representations, showing stronger illusions for small and fantastical (monkey) fake hands compared with adults. Conversely, using a task indirectly capturing changes in hand size, we found that children and adults demonstrated statistically equivalent increases and decreases in hand size following illusions over large and small hands, respectively. Interestingly, at baseline children showed a bias in reporting larger hand size judgments that decreased with age. Finally, we did not find a relationship between individual differences in fantasy proneness and illusion strength for a fantastical (monkey) hand for children or adults, suggesting that developmental changes of top-down constraints are not purely driven by more diffuse boundaries between imagination and reality. These data suggest that high-level constraints acting on our multisensory body experience change during development, allowing children a more flexible bodily experience compared with adults.