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 271 records · Page 15Linked to original sources
PubMed1990

Shape, size and relative space position perception in neglect patients.

Shape, size and relative position in space perception were tested in 17 right brain damaged (RBD) patients with neglect symptoms, 10 RBD patients without neglect and 11 controls. Simultaneous pair comparison task in free vision was used. Two arrangements of the visual display were used: side by side and top-bottom. Neglect patients' performance was comparable to RBD and controls in the shape and size test, but was below the other groups in the relative space position test. The selective failure of neglect patients in the position task did not depend on the spatial arrangement of the visual display, which may indicate a general perceptual deficit, rather than a deficit restricted to the neglect hemifield.

Aged↗
PubMed2001

Penis size: Survey of female perceptions of sexual satisfaction.

BACKGROUND: Does the size of the male penis, in terms of length or width, make a difference in female sexual satisfaction? METHOD: To study the effect of penis width vs. length on female sexual satisfaction, 50 sexually active female undergraduate students were asked which felt better, i. e., was penis width or length more important for their sexual satisfaction. RESULTS: None reported they did not know, or that width and length were equally satisfying. A large majority, 45 of 50, reported width was more important (p <.001). CONCLUSION: Implications are discussed, including the fact that the data seem to contradict Masters and Johnson about penis size having no physiological effect on female sexual satisfaction.

Journal Article↗
PubMed1994

Black and white females' perceptions of ideal body size and social norms.

Different cultural norms and standards for appropriate female body size might contribute to the disparity in obesity rates between black and white adult females (46.0% and 24.6% respectively). The purpose of this study was to measure adolescents' perceptions of ideal size and social norms regarding female body size as well as adolescents' perceptions of significant others' evaluation and expectations of the adolescents' body size. Subjects included 437 adolescent girls (247 white and 190 black) aged 13 to 19 (x = 14.9, SD = .979) from six randomly selected public schools. The subjects, heights and weights were measured. Responses to a body image questionnaire and a series of nine female body drawings (arranged ordinally, 1 to 9, from thinnest to heaviest) were analyzed using the General Linear Model and Logistic Regression. The female body size considered ideal by black females was significantly larger than the size selected as ideal by white females (x = 3.47 and x = 3.13 respectively, p < 0.001). Black females were two times more likely than white females to describe themselves as thinner than other girls their age (O.R. = 2.01, 95% C.I. 1.34, 3.01) and seven times as likely to say that they were not overweight (O.R. = 7.08, 95% C.I. 3.72, 13.45). White females wanted to be a smaller size than they currently were and felt encouraged by significant others to lose weight or reduce their size. Black females did not indicate as great a desire as whites to be smaller and they tended to feel that their size was considered satisfactory by significant others. Only subjects from the low SES group perceived that significant others wanted them to gain weight. The differences between black and white subjects' beliefs and perceptions about body size norms may explain, in part, why heavier body weights persist in some cultural groups.

Adolescent↗
PubMed2006

Representation of object size in the somatosensory system.

In this study we investigate the haptic perception of object size. We report the results from four psychophysical experiments. In the first, we ask subjects to discriminate the size of objects that vary in surface curvature and compliance while changing contact force. We show that objects exhibit size constancy such that perception of object size using haptics does not change with changes in contact force. Based on these results, we hypothesize that size perception depends on the degree of spread between the digits at initial contact with objects. In the second experiment, we test this hypothesis by having subjects continuously contact an object that changes dynamically in size. We show that size perception takes into account the compliance of the object. In the third and fourth experiments we attempt to separate the individual contributions of proprioceptive and cutaneous input. In the third, we test the ability of subjects to perceive object size after altering the sensitivity of cutaneous receptors with adapting vibratory stimuli. The results from this experiment suggest that initial contact is signaled by the cutaneous slowly adapting type 1 afferents (SA1) and/or the rapidly adapting afferents (RA). In the last experiment, we block cutaneous input at the site of contact by anesthetizing the digital nerves and show that proprioceptive information alone provides only a rough estimate of object size. We conclude that the perception of object size depends on inputs from SA1 and possibly RA afferents, combined with inputs from proprioceptive afferents that signal the spread between digits.

Adult↗
PubMed1989

Body-image disturbances in bulimia nervosa: influences of actual body size.

This study evaluated body-image distortion and ideal body-size preferences in 423 nonbulimic women and 108 bulimics. Analyses of covariance were utilized to compare the bulimic and nonbulimic groups on measures of current and ideal body size. Weight was used as a covariate to evaluate the influence of actual body size on perception of current body size and selection of ideal body size. Bulimics chose current body sizes that were significantly larger than those picked by nonbulimics regardless of actual body size. Bulimics also chose thinner ideal body sizes than did nonbulimics, regardless of actual body size. These results suggest that body-image distortion and extreme preference for thinness are a fundamental characteristic of bulimia nervosa. These results were discussed in terms of how perception of a large body size and preference for a very thin body size might interact to produce a high degree of dissatisfaction and overconcern with body size in bulimia nervosa.

Adult↗
PubMed2002

Heaviness perception. I. Constant involvement of haptically perceived size in weight discrimination.

With visual input blocked, subjects in this study utilized fingertips only to investigate the involvement of haptically perceived size in heaviness perception among humans. The objects used for testing consisted of three sets - copper (CP), aluminum (AL), and plastic (PL) - of ten cubes of various weights (0.05-0.98 N). All of the cubes were covered with a smooth vinyl material to eliminate any extraneous input concerning the actual composition. Screens enclosed the working space to eliminate any possible visual cues. Each comparison was between a pair of cubes of the same material to eliminate the effect of density. Fifteen subjects ( M=19.2, SD=0.68 years) attempted to judge differences in heaviness between the first and second cube in each trial that had been handed to them by the experimenter and were grasped between the thumb and the index finger. A total of 340 trials with 70 combinations of weight composed of 160 ascending trials (heavier), 160 descending trials (lighter), and 20 identical weight trials were pseudo-randomly presented to each subject for each material. Combinations of difference in weight and the number of trials were identical for all materials so that haptic size was regarded as the single independent factor. Accuracy of the subjects' responses for identical weight differences that resulted from placing a pair of cubes of the same combination was compared among the three materials. It was observed that a material like CP that had a lesser size effect facilitated significantly more accurate discrimination of the identical weight differences than PL with its greater size effect. This suggests that small changes in haptic size by the fingertips have a direct influence on heaviness perception when comparing objects of equal density. This finding, therefore, can be considered analogous to the size-weight illusion when comparing objects of unequal density. The findings of this study also suggest the constant involvement of haptic size in heaviness perception by humans along with the existence of a processing mechanism that integrates the factors of weight and haptic size in which heaviness increases either as weight increases or as size decreases, and vice versa.

Adolescent↗
PubMed1963

Cat's ability to discriminate oblique rectangles.

Cats were trained to discriminate either between a horizontal and vertical rectangle or between two oblique rectangles, one at 45 degrees , the other at 135 degrees to horizontal. All animals were first trained with both shapes (one in each orientation) presented together, and then retrained with only one shape shown at a time. Throughout the experiment the animals being trained with oblique rectangles performed as well as those being trained with horizontal and vertical rectangles. This finding is in marked contrast with results obtained from other species. The results suggest that the ability of a species to discriminate between rectangles in different orientations may depend upon the relative numbers of cells in the visual system having receptive fields in each orientation.

Animals↗