Illusory figures: Individual differences apparent depth and lightness

When the luminance of a pattern that induces a sharp-edged illusory circle was decreased, both illusory contrast with the surround and the illusory depth difference between that circular area and the inducing elements reliably increased. Thus, changes in both of these effects apparently participate in (contribute to) the increased overall salience that had previously been found with decreased luminance. However, among individuals, the correlation between this improvement in contrast and this increase in depth was exceedingly small.     

Infants’ sensitivity to the depth cue of shading

Five- and 7-month-old infants were tested for sensitivity to the depth cue of shading. Infants were presented with two displays: a surface in which a convexity and a concavity were molded and a photograph in which shading specified a convexity and a concavity. Each display was presented under both monocular and binocular viewing conditions. Reaching was observed as the dependent measure. Infants in both age groups reached preferentially for the actual convexity in both the monocular and binocular viewing conditions. In the monocular photograph condition, the 7-month-olds reached preferentially for the apparent convexity specified by shading, indicating that they perceived it to be an actual convexity. These infants showed no significant reaching preference in the binocular photograph condition. This finding rules out interpretations of the infants’ reaching not based on perceived depth. The results therefore suggest that the 7-month-olds perceived depth from shading. The 5-month-olds showed no significant reaching preferences when viewing the photograph; thus, they showed no evidence of depth perception from shading. These findings are consistent with the results of a number of studies that have investigated infants’ sensitivity to pictorial depth cues. Together, these studies suggest that the ability to perceive depth from pictorial cues may first develop between 5 and 7 months of age.     

Perception of social distributions

Accurate representation of the distribution of social attitudes and behaviors can guide effective social behavior and is often essential for correct inferences. We examined the accuracy of people's beliefs about the distributions of a large number of attitudinal and behavioral dimensions. In two studies we measured actual attitudes and behaviors in a student population, and we assessed beliefs by asking subjects to estimate the distribution of 100 students on these dimensions. We examined the accuracy of subjects' perceptions of the means, standard deviations, and distribution shapes. Subjects showed a number of systematic biases, including overestimation of dispersion and overestimation of the means of behavioral distributions and a false consensus bias, but their overall accuracy was impressive.     

Response pattern analysis of the Hand Test: age differences

Extended the literature on age differences on the Hand Test using a multivariate model to examine absolute and relative differences in response. Participants were 47 adults (M age = 22.47 yrs.), 24 males and 23 females; and 45 older adults (M age = 64.87 yrs.), 21 males and 24 females. Data were analyzed in terms of percentage of response and absolute frequency of specific responses, between the age groups. Results indicated similar findings to those previously reported for the Hand Test, though magnitude of personality deterioration or withdrawal was lessened, for the percentage analysis. Results indicated the importance of using both absolute frequency of response and percentage of response in the interpretation of projective test data, especially for older adults.     

Amount of information about the attitude object and attitude-behavior consistency

The synthesis of two separate lines of inquiry--research on information integration and longitudinal studies of attitudes--prompted the hypothesis that the degree of consistency between attitudes and behavior will increase as a function of the amount of information available about the attitude object. The hypothesis was tested in three separate longitudinal studies, ranging in length from 4 days to 4 months, that investigated the following behaviors: voting for candidates for political office, voting for two social policy election initiatives, and having an influenza vaccination. In support of the hypothesis, in each study, amount of information moderated the consistency between attitudes and behavior; and the significance of this relation remained even after controlling for the effects of a number of other potential moderators, including prior direct behavioral experience with the attitude object and attitude certainty. Consistent with previous research, direct behavioral experience was also a determinant of attitude-behavior consistency, and for the behavior of having an influenza vaccination, this relation was independent of the effect of amount of information. The discussion focuses on the interrelation among moderators of attitude-behavior consistency and on the theoretical implications of the findings.     

Statistical consistency and hypothesis testing for nonmetric multidimensional scaling

The properties of nonmetric multidimensional scaling (NMDS) are explored by specifying statistical models, proving statistical consistency, and developing hypothesis testing procedures. Statistical models with errors in the dependent and independent variables are described for quantitative and qualitative data. For these models, statistical consistency often depends crucially upon how error enters the model and how data are collected and summarized (e.g., by means, medians, or rank statistics). A maximum likelihood estimator for NMDS is developed, and its relationship to the standard Shepard-Kruskal estimation method is described. This maximum likelihood framework is used to develop a method for testing the overall fit of the model.     

Flicker fusion frequency and organic syndrome in alcoholics

Flicker fusion frequencies of 48 healthy controls and of 35 alcoholics were measured to detect possible associations between flicker fusion and signs of nonspecific brain damage, the aim of the study. FFF was statistically significantly lower in patients addicted to alcohol than in healthy subjects. Lower flicker fusion frequencies were associated with the severeness of organic psychosis as rated psychopathologically. The hypothesis that addiction to alcohol is a sign of diffuse, nonspecific, organic brain damage was discussed.     

Behavioral analysis of sexual dysfunction in Hansen's disease

Human sexual behavior is an interactive process including CNS, hormonal, and sex-gland activities. This process can be disrupted in males who have Hansen's disease if testicular atrophy occurs. Elevations of centrally mediated luteinizing hormone and deficient testosterone levels were found in a male with Hansen's disease whose insufficient erections were secondary to atrophic testes. Quasi-experimental (A-B) analysis provided evidence for the efficacy of testosterone treatment for such a condition.