-
Perception Jan 2021This study aimed to test differences in drawn size of familiar objects of different physical size in haptic drawings produced by blindfolded sighted participants. Using...
This study aimed to test differences in drawn size of familiar objects of different physical size in haptic drawings produced by blindfolded sighted participants. Using two sizes of the foil sheets on which they made convex drawings, they drew one object per foil. The results showed that the size of drawings increased linearly with the rising rank of real-world size. Although larger drawings were created on larger foils than on smaller ones, the ratio of the object drawn size within the foil sheet size did not differ across foil sizes. Hence, canonical size-a phenomenon known so far from studies on the visual domain-revealed here in a task performed in the haptic domain.
PubMed: 33446068
DOI: 10.1177/0301006620983697 -
Vision (Basel, Switzerland) Jul 2022Prior 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...
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.
PubMed: 35893758
DOI: 10.3390/vision6030041 -
British Journal of Psychology (London,... Nov 2021Estimating the size of bodies is crucial for interactions with physical and social environments. Body-size perception is malleable and can be altered using visual...
Estimating the size of bodies is crucial for interactions with physical and social environments. Body-size perception is malleable and can be altered using visual adaptation paradigms. However, it is unclear whether such visual adaptation effects also transfer to other modalities and influence, for example, the perception of tactile distances. In this study, we employed a visual adaptation paradigm. Participants were exposed to images of expanded or contracted versions of self- or other-identity bodies. Before and after this adaptation, they were asked to manipulate the width of body stimuli to appear as 'normal' as possible. We replicated an effect of visual adaptation such that the body-size selected as most 'normal' was larger after exposure to expanded and thinner after exposure to contracted adaptation stimuli. In contrast, we did not find evidence that this adaptation effect transfers to distance estimates for paired tactile stimuli delivered to the abdomen. A Bayesian analysis showed that our data provide moderate evidence that there is no effect of visual body-size adaptation on the estimation of spatial parameters in a tactile task. This suggests that visual body-size adaptation effects do not transfer to somatosensory body-size representations.
Topics: Adaptation, Physiological; Bayes Theorem; Body Image; Humans; Touch; Touch Perception
PubMed: 34120340
DOI: 10.1111/bjop.12514 -
PsyCh Journal Feb 2023The size-eccentricity effect is a perceptual distortion phenomenon in which a peripherally located object is perceived to be smaller than a centrally located object....
The size-eccentricity effect is a perceptual distortion phenomenon in which a peripherally located object is perceived to be smaller than a centrally located object. Although the increase in apparent object size caused by attention has been documented, little is known about the effect of different sizes of attentional focus on object appearance. The present study investigated how different sizes of attentional focus affect the size-eccentricity effect using a spatial pre-cueing paradigm. Additionally, we examined the influence of different task types on size perception. A peripheral object following a small attentional focus appeared larger, without observation of the size-eccentricity effect. In contrast, a peripheral object appeared smaller following a large attentional focus in both larger and smaller judgement tasks. These results suggest that the relative size of the attentional focus has opposite effects on the perception of object size, independent of task type. Furthermore, in addition to the structural properties of the retina and the locus of attention, the size of attentional focus determines the extent to which an object appears smaller in the periphery. The present study complements the attentional attraction field model of the size and density of population receptive fields in V1 and further explains how the effect of attention is restricted by retinal structure.
Topics: Humans; Attention; Size Perception; Judgment; Visual Perception
PubMed: 36167945
DOI: 10.1002/pchj.604 -
International Journal of Environmental... Sep 2020The study aimed to assess the association between body image perception and (dis)satisfaction and sociodemographic and behavioral factors in the elderly, using...
The study aimed to assess the association between body image perception and (dis)satisfaction and sociodemographic and behavioral factors in the elderly, using multinomial logistic regression. Data were analyzed for 1686 women and 1499 men participating in the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil). Men with less schooling and women with lower per capita income showed higher odds of underestimating their body size. Former smokers of both sexes showed higher odds of overestimating their body size; lower schooling and lower per capita income decreased these odds. Increasing age, lower per capita income, and smoking increased the odds of dissatisfaction due to thinness in men, and married marital status decreased these odds. In women, low per capita income, weekly consumption of vegetables, and smoking increased the odds of such dissatisfaction. Factors that increased the odds of dissatisfaction due to excess weight in both sexes were primary or secondary schooling and former smoking. In women, low per capita income, weak physical activity, weekly consumption of vegetables, and excessive alcohol intake also increased the odds of such dissatisfaction. The results suggest that improved living conditions and the adoption of healthy behaviors can help reduce misperceived negative body image among elderly.
Topics: Adult; Aged; Body Image; Body Size; Brazil; Cross-Sectional Studies; Female; Humans; Longitudinal Studies; Male; Personal Satisfaction; Size Perception
PubMed: 32933014
DOI: 10.3390/ijerph17186632 -
Attention, Perception & Psychophysics Feb 2020The visual system can efficiently summarize various lower-level and higher-level features of ensembles. However, no research to date has directly investigated how...
The visual system can efficiently summarize various lower-level and higher-level features of ensembles. However, no research to date has directly investigated how different features interact with each other within a single summary and whether people can efficiently report an integrated summary of two feature dimensions. In the first two experiments, we specifically investigated whether individuals can integrate spatial and size information to report a bound spatial summary, the center of mass (CoM), as efficiently as the centroid, which is devoid of size information. Both experiments revealed that viewers were equally accurate in extracting the centroid and the CoM, with the size distribution inadvertently affecting the centroid estimates. In the final experiment, we investigated whether encouraging observers to attend to individual item size would cause the centroid estimates to be biased toward the CoM. When item size was task-irrelevant, as in the centroid task, observers were able to selectively focus on spatial location, eliminating any impact from the size distribution. Taken together, these findings demonstrate that viewers are capable of extracting integrated summaries, possibly through a mechanism that allows them to represent the spatial distribution of sizes. We discuss possible mechanisms that may support the extraction of integrated summaries, and highlight the need to consider multilevel mechanisms extending beyond simple feature- and object-based mechanisms.
Topics: Adult; Female; Humans; Male; Photic Stimulation; Size Perception; Space Perception; Young Adult
PubMed: 31898066
DOI: 10.3758/s13414-019-01944-9 -
BMC Family Practice Feb 2021The attitudes towards obesity may have an important role on healthier behavior. The goal of the present study was to explore the attitudes towards obesity and to...
BACKGROUND
The attitudes towards obesity may have an important role on healthier behavior. The goal of the present study was to explore the attitudes towards obesity and to investigate how these attitudes were associated with lifestyle-changing behavior among the patients attending primary care centers, health care professionals and public health experts.
METHODS
This cross-sectional survey study was performed in 10 primary care offices in different regions in Lithuania and in 2 public health institutions. Nine hundred thirty-four patients, 97 nurses, 65 physicians and 30 public health experts have filled the questionnaire about attitudes towards obesity and presented data about lifestyle-changing activities during last 12 months. The attitudes were compared between different respondent groups and factors associated with healthier behaviors were analyzed among overweight/obese individuals in our study population.
RESULTS
Participants failed to visually recognize correct figure corresponding to male and female with obesity. Majority of respondents' perceived obesity as a risk factor for heart diseases and diabetes but had less knowledge about other diseases associated with weight. About one third of respondents changed their lifestyle during last 12 months. Overweight individuals with age < 45 years (OR 1.64, 1.06-2.55; p = 0.025) were more likely and those who overestimated current weight (OR 0.44, 0.20-0.96; p = 0.036) less likely to change their lifestyle. Disappointment with their current weight (OR 2.57, 1.36-4.84; p = 0.003) was associated with healthier behavior among participants with obesity.
CONCLUSION
Participants had similar body size perception and knowledge about obesity. Younger age had significant association with lifestyle changing behavior among overweight individuals and disappointment with current weight among obese participants.
Topics: Body Mass Index; Cross-Sectional Studies; Female; Health Knowledge, Attitudes, Practice; Humans; Life Style; Male; Obesity; Overweight; Physicians; Public Health; Size Perception
PubMed: 33588766
DOI: 10.1186/s12875-021-01383-2 -
Journal of Neurophysiology Oct 2019It is tempting to describe human reach-to-grasp movements in terms of two, more or less independent visuomotor channels, one relating hand transport to the object's... (Review)
Review
It is tempting to describe human reach-to-grasp movements in terms of two, more or less independent visuomotor channels, one relating hand transport to the object's location and the other relating grip aperture to the object's size. Our review of experimental work questions this framework for reasons that go beyond noting the dependence between the two channels. Both the lack of effect of size illusions on grip aperture and the finding that the variability in grip aperture does not depend on the object's size indicate that size information is not used to control grip aperture. An alternative is to describe grip formation as emerging from controlling the movements of the digits in space. Each digit's trajectory when grasping an object is remarkably similar to its trajectory when moving to tap the same position on its own. The similarity is also evident in the fast responses when the object is displaced. This review develops a new description of the speed-accuracy trade-off for multiple effectors that is applied to grasping. The most direct support for the digit-in-space framework is that prism-induced adaptation of each digit's tapping movements transfers to that digit's movements when grasping, leading to changes in grip aperture for adaptation in opposite directions for the two digits. We conclude that although grip aperture and hand transport are convenient variables to describe grasping, treating grasping as movements of the digits in space is a more suitable basis for understanding the neural control of grasping.
Topics: Fingers; Hand Strength; Humans; Illusions; Motor Skills; Movement; Size Perception
PubMed: 31339802
DOI: 10.1152/jn.00123.2019 -
Children (Basel, Switzerland) Jul 2023This secondary data analysis study aimed to examine the associations between 1) body size perception (BSP) and body size dissatisfaction (BSD) and 2) lifestyle behaviors...
This secondary data analysis study aimed to examine the associations between 1) body size perception (BSP) and body size dissatisfaction (BSD) and 2) lifestyle behaviors and BSP and BSD in adolescents. The study pooled cross-sectional data from two studies ( = 301) performed in adolescents. Weight and height were measured, while lifestyle behaviors and perceived actual and desired body size variables were self-reported. Linear regression analysis assessed the contribution of sex and zBMI to BSP and BSD scores. Pearson's correlation explored associations between BSP and BSD. Cohen's effect sizes compared satisfied and dissatisfied adolescents within the underestimators subgroup. A positive association between BSP and BSD scores was observed among girls living with normal-weight and overweight/obesity only (r = 0.26; ≤ 0.001 and r = 0.38; < 0.05, respectively). Underestimators who were satisfied with their body size showed a moderate effect size for a lower zBMI, a small effect size for lower screen time, and higher sleep duration compared to dissatisfied underestimators. Underestimation was associated with more body size satisfaction in adolescent girls with normal weight and overweight/obesity, suggesting a protective effect of underestimation. These findings support the hypothesis that body size satisfaction and underestimation in adolescents is associated with healthier lifestyle behaviors.
PubMed: 37508760
DOI: 10.3390/children10071263 -
Clinical & Experimental Optometry May 2020This review of the literature in visual search superiority in autism was intended to quantify the effect size of visual search performance in autism. Not all studies... (Review)
Review
This review of the literature in visual search superiority in autism was intended to quantify the effect size of visual search performance in autism. Not all studies have found an advantage within the autistic population. Early findings on search superiority have led to different proposed mechanisms for the observed results. A review of feature search found that the effect size was low across 15 included studies (Cohen's d 0.089 [-0.150 to 0.293]). However, the effect size was larger for more complex search paradigms using a conjunctive search strategy with Cohen's d showing a moderate effect of 0.223 (0.087 to 0.293). The majority of studies were limited to a small sample size and biased toward the high-functioning end of the autistic spectrum. The overall results indicate that within the autism spectrum disorder population there is a low to moderate search advantage compared to typically developing individuals.
Topics: Attention; Autism Spectrum Disorder; Discrimination Learning; Humans; Vision, Low; Visual Perception
PubMed: 31282016
DOI: 10.1111/cxo.12940