Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Size Perception”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 109 records · Page 6Linked to original sources
PubMed1988

Comparison of the human perception of hole size by the tongue and the fingers.

Thirty blindfolded subjects assessed the size of holes (2.4-19.1 mm dia) that were presented to the tongue by using their fingers to select a matching hole from a comparator series of 38 holes (1.6-25.4 mm dia). Subjects consistently overestimated the size of holes less than 10 mm, but there was little disparity for holes greater 14 mm in diameter. The relationship between the size of hole presented to the tongue and that judged by the fingers to be of equal size was not linear across the range tested. The illusion, expressed as the ratio of apparent size to real size, could be described as an hyperbolic function of stimulus size.

Adolescent↗
PubMed1984

Premenstrual syndrome: weight, abdominal swelling, and perceived body image.

One hundred forty-eight menstrual cycles were studied in 52 women, and in each cycle various parameters were measured to determine an objective means of assessing the syndrome. Daily mood assessment, body weight, plasma 17 beta-estradiol levels, and plasma progesterone levels were measured. The abdominal dimensions were measured in the lateral and anteroposterior diameters at the level of the umbilicus and 10 cm below; at the same time the same dimensions were measured as perceived by the patient. Mood score showed a marked increase during the premenstrual phase of each cycle. The symptom of bloatedness was marked during the premenstrual phase of the cycle. Despite these highly elevated scores for bloatedness there was no increase in body weight or the measured body dimensions in any plane. However, the patient's perception of body size did increase, and the discrepancy between the perceived body size and the actual body size (perception error) was significant.

Body Image↗
PubMed2004

Evidence for impaired visual context processing in schizotypy with thought disorder.

Visual context processing was examined in relation to schizotypy in a large nonclinical university population. Schizotypal status was assessed with the Schizotypal Personality Questionnaire (SPQ) [Schizophr. Bull. 17 (1991) 555]. Schizotypal (n=32) and non-schizotypal (n=37) subjects were tested on a contour integration task (where context processing is necessary for good performance) and a visual size perception task (where context processing impairs accurate performance). In addition, a short form of the Thought Disorder Index (TDI) [Psychol. Assess. 5 (1993) 75] was administered to 28 schizotypal subjects. Thought disordered schizotypal subjects showed significantly impaired performance on the contour integration task but more accurate performance on the visual size perception task. These results support the hypothesis that deficits in visual context processing are the manifestation of a larger disturbance of cognitive coordination in schizotypy and schizophrenia.

Adult↗
PubMed2001

Body dissatisfaction among White and African American male and female college students.

Body size perception has been shown to be highly influenced by cultural factors including race. This study assessed body size perceptions of a convenience sample of college students (N=630). Included in a paper-and-pencil survey were current height and weight (body mass index (BMI)=wt [kg]/ht(2) [m]), perceived BMI, desired MI and perceptions of BMIs desired by others. Also assessed were perceptions of underweight, acceptable weight and overweight/obesity. African American females were found to have a higher current BMI than Whites (P< or =.001), higher desired BMI (P< or =.001) and higher BMI perceived to be desired by others (P< or =.001). African American and White males did not differ on any of these measures. Most (83%) underweight (BMI<19) African American females perceived themselves as underweight while only about one-half of underweight (56%) White females perceived themselves as underweight. Almost half (43%) of White females and about a fourth (27%) of African American females of acceptable BMI range (BMI=19-25) desired to be in the underweight range. Of those who were overweight (BMI=25-30), 20% of the Whites and only 3.0% of the African Americans chose an underweight silhouette as being desired. While African Americans and White males tended to have similar perceptions that there remains sociocultural influences in African American females regarding acceptance of a large body size.

Journal Article↗
PubMed2003

Scaling of letter size and contrast equalises perception across eccentricities and set sizes.

Double E(2)N(2) scaling, i.e. magnifying size and contrast, allows modelling of the deterioration of face recognition performance with increasing eccentricity (E) and the size (N) of the set from which a target face has to be identified. E(2) and N(2) values represent the eccentricities and set sizes at which stimulus size and contrast must double in order to keep performance unchanged, whilst parameter K represents the multiplicative interaction between E and N. In the current study we investigated whether double E(2)N(2) scaling can model performance deterioration with increasing eccentricity and set size in letter perception too. Contrast sensitivity for letter perception was investigated as a function of letter size at N=1-8 and E=0 degrees -10 degrees. The superimposition of contrast sensitivity functions produced two scaling surfaces, one for letter size and another for contrast, which allowed modelling of the changes in letter perception with increasing E and N. With increasing eccentricity/set size the change of scale was much faster for contrast than letter size. Thus, in letter perception, contrast scaling was more important than spatial scaling. When compared with face perception, the change of spatial scale with increasing eccentricity was slower for letters whereas the change of contrast scale was similar for both. With increasing set size the changes of both spatial and contrast scales are faster for faces. In spatial scaling the interaction between eccentricity and set size was similar for letters and faces whereas in contrast scaling letters showed no interaction. Thus, letter perception was less affected by eccentricity and set size than face perception.

Adult↗
PubMed1991

Transformation theory of size judgment.

Perception of size is assessed by having observers adjust a comparison target at a fixed distance to match the size of a standard located at different distances. Results depend on instructions, target orientation, and available stimulus cues. A mathematical theory assumes that the brain performs an inverse transformation on the proximal information impinging on the retina to recover the original distal size of the target. Results depend on the target visual angle, and the effective target distance and orientation applied in performing the inverse transformation. Effective values are linked to instructions, target location, and stimulus cues. Two models are developed and successfully fit to empirical data. One emphasizes the distance parameter; the second, the orientation parameter.

Attention↗
PubMed2002

Development of the Children's Body Image Scale.

OBJECTIVE: The aim of this study was to develop a gender-appropriate pictorial scale to measure body image in young children based on a measurable index of adiposity. METHOD: Pictorial scales for boys and girls containing seven body pictures representing standard percentile curves for body mass index (BMI) for healthy children were developed. The Children's Body Image Scale (CBIS) was administered to 312 children aged between 7 and 12 years. RESULTS: Accuracy of body size perception, indicated by the correlation between actual and perceived BMI category figure, developed with age, girls acquiring accuracy earlier than boys. Whereas girls developed a good accuracy (r =.60, p <.001, 10-12 years), in boys, the correlation, though significant, was not strong (r =.35, p <.01, 10-12 years). There was a consistent bias towards underestimation of body size using this technique. There was a high frequency of body size dissatisfaction across all the age ranges, 48% girls and 36% boys wished to have a smaller body figure than their own, and only 10% of girls and 20% boys wished to have a larger body figure. Construct validity was assessed in a subset of 153 children in which additional measures of restrained eating (DEBQ-R) and body esteem were available. From the age of 8 years, the CBIS provides a good measure of body dissatisfaction. CONCLUSIONS: The CBIS provides a good measure of body size perception in girls and an adequate measure in boys aged 8 years and older. It also provides a good measure of body size dissatisfaction in children. Internalization of a thin body ideal takes place at a young age, many children desiring a BMI below the average norm.

Body Constitution↗
PubMed2001

Specific body image pathology in acute schizophrenia.

Despite a wide phenomenological interest in body image pathology in schizophrenia, there has been little systematic empirical research. This study aimed at establishing the specificity of body image pathology in patients with schizophrenia, its changes during acute treatment, and its association with other symptom factors. Cognitive (thoughts/beliefs regarding the body--body concept), affective (body satisfaction--body cathexis) and perceptual (body size estimation--body schema) facets of body image and psychopathology were assessed in in-patients with paranoid schizophrenia (N = 60), schizoaffective disorder (N = 19), depressive disorder (N = 40) and anxiety disorder (N = 28) at admission, and after 2 and 4 weeks of treatment. Body size perception was also assessed in a sample of healthy subjects (N = 44). Patients with paranoid schizophrenia/schizoaffective disorder showed under-estimation of lower extremities at each time point. They expressed a higher degree of body concept disturbances at admission, but not at later stages. In a factor analysis, body perception and body concept loaded on distinct factors, which were separate from positive symptoms, negative symptoms, and anxiety. Patients with acute paranoid schizophrenia and schizoaffective disorder seem to have a specific and consistent disturbance of body size perception, which might indicate a dysfunction of sensory information processing.

Acute Disease↗
PubMed2004

Relationship between oral sensitivity and masticatory performance.

The size of a bolus determines how it will be manipulated in the mouth and swallowed. We hypothesized that mucosal sensitivity would be important for masticatory function. The accuracy of solid object size perception, spatial acuity, and food particle size reduction during mastication were measured in 22 healthy adults with/without topical anesthesia of their oral mucosa. Topical anesthesia had no effect on the perception of sphere sizes, but significantly reduced spatial sensitivity. Without anesthesia, there was a correlation between an individual's ability to perceive the sizes of steel spheres (diameter, 4-9 mm) and the sizes of food particles chewed for 15 cycles and at swallowing. There was no correlation between spatial sensitivity and food particle size. We suggest that the stimuli used to test two-point discrimination stimulates only superficial receptors, which involve light touch and are easily anesthetized, while the spheres might excite more deeply-set receptors. The latter appear to be more important for masticatory performance and swallowing.

Adult↗