Apparent contrast of suprathreshold gratings varies with stimulus orientation

Human contrast sensitivity is known to vary with both stimulus spatial frequency and orientation. Previous research has indicated, however, that the apparent contrast of a sinusoidal grating is independent of spatial frequency at suprathreshold levels. We have found that the apparent contrast of suprathreshold gratings is not independent of its orientation. Observers adjusted the apparent contrasts of vertical and oblique gratings to match a 40% standard. Contrast match deviations were found at a number of spatial frequencies, indicating a lack of contrast constancy with stimulus orientation. The apparent contrast of gratings in different orientations could not be predicted in any simple fashion from either contrast threshold differences or ratios.     

Validation of the Differential Emotions Scale in 613 mothers

Mothers (N=613) with infants who took the Differential Emotions Scale (DES) were compared in a cross-validation study by factor analysis to 957 high school and college students. Despite differences in factor-analytic technique, similarities in factor structure suggested that the DES discriminates the majority of fundamental emotions as posited by Izard.Robert Emde is supported by Research Scientists Award No. 5 KO5 MH 36808 and NIMH Project Grant No. 2 RO1 MH 22803. The authors wish to acknowledge the critical support of the Developmental Psychobiology Research Group, Department of Psychiatry, University of Colorado Medical School, and wish to express their gratitude to Carroll Izard for allowing us to publish his factor-analytic results.     

Importance of the overall similarity of objects of adults' and children's classifications

Previous work has shown that adults and older children tend to classify multi-dimensional objects by identity on one dimension, whereas children under 8 years of age tend to classify these same objects by a relation of overall similarity. The present study investigated the hypothesis that this developmental trend is restricted to the classification of simple objects that differ only by limited amounts on a few dimensions. The specific hypothesis was that overall-similarity relations structure both adults' and children's classifications of heterogenous objects (objects that differ in a variety of ways). This hypothesis was suggested by the correspondence between the structure of young children's classifications and the structure of natural categories. The result of two experiments supported the hypothesis. When the to-be-classified objects varied simultaneously on relatively many dimensions, adults as well as children constructed classifications that maximized within-category similarity on all varying dimensions. The implications of these results for accounts of the perception of multidimensional relations and classificatory behavior are discussed.     

Sharing behavior and racial preference in children

Three groups of white children, 43 preschoolers and first-graders, 46 third-graders, and 44 fifth-graders, were asked to choose either a white child or a black child as a recipient of sharing and also as a companion for several social interaction situations ordered for social distance. The preschoolers and first-graders preferred to share and interact socially with the white child. The third-graders and the fifth-graders displayed a weaker preference for the white child over the black child on the sharing task, no preference in situations of high social distance, and a preference for the white child in situations of low social distance. The results from ancillary measures suggested that the choices of the younger children were motivated by a generalized color preference but that the choices of the older children were guided by an awareness of the social meaning of racial categories.The investigation was supported by the Research Advisory Council of East Tennessee State University.     

Postdecision evaluation of choice alternatives as a function of valence of alternatives,choice, and expected delay of choice consequences

The effects of valence of alternatives, choice, and expected delay of choice consequences on postdecision evaluations of choice alternatives were studied by either giving subjects a choice between two experimental tasks (both either pleasant or unpleasant) or assigning subjects their initially preferred task. Crosscutting valence and choice, subjects expected either no delay, 10-min delay, or 30-min delay before engaging in the task. All subjects evaluated both tasks immediately after the delay instructions but before experiencing the actual delay. Results confirmed the expected dissonance effect; that is, an upward evaluation of the chosen alternative and a downward evaluation of the rejected alternative, relative to no-choice conditions. Moreover, the relative upward evaluation of the chosen alternative increased as the expected delay decreased. Valence was not found to interact with other variables. The results are discussed in terms of differential salience of choice alternatives.     

Negative attitudes toward masturbation and pelvic vasocongestion: A thermographic analysis

The present study examined differences in pelvic vasocongestion as a function of negative attitudes toward masturbation. Pelvic vasocongestion was measured thermographically, which is a noninvasive means of detecting and photographing individual heat patterns to indicate physiological condition and functional changes within. The results indicated that women, with positive attitudes toward masturbation, who read an erotic story, experienced the greatest increase in pelvic vasocongestion. This and other findings were discussed in terms of masturbation acting to facilitate the patterning of sexual arousal and orgasmic functioning, especially in regard to creating the capacity for pelvic engorgement.