Comparison and contrast in perceptual categorization

People categorized pairs of perceptual stimuli that varied in both category membership and pairwise similarity. Experiments 1 and 2 showed categorization of 1 color of a pair to be reliably contrasted from that of the other. This similarity-based contrast effect occurred only when the context stimulus was relevant for the categorization of the target (Experiment 3). The effect was not simply owing to perceptual color contrast (Experiment 4), and it extended to pictures from common semantic categories (Experiment 5). Results were consistent with a sign-and-magnitude version of N. Stewart and G. D. A. Brown's (2005) similarity-dissimilarity generalized context model, in which categorization is affected by both similarity to and difference from target categories. The data are also modeled with criterion setting theory (M. Treisman & T. C. Williams, 1984), in which the decision criterion is systematically shifted toward the mean of the current stimuli.     

Believe it or not: on the possibility of suspending belief

We present two experiments that cast doubt on existing evidence suggesting that it is impossible to suspend belief in a comprehended proposition. In Experiment 1, we found that interrupting the encoding of a statement's veracity decreased memory for the statement's falsity when the false version of the statement was uninformative, but not when the false version was informative. This suggests that statements that are informative when false are not represented as if they were true. In Experiment 2, participants made faster lexical decisions to words implied by preceding statements when they were told that the statements were true than when the veracity of the statements was unknown or when the statements were false. The findings suggest that comprehending a statement may not require believing it, and that it may be possible to suspend belief in comprehended propositions.     

Gender differences in patterns of emotional distress following heart transplantation

The study provides the first empirical evaluation of gender differences in psychological symptomatology and DSM-III-R major depressive disorder (MDD) across the first year following heart transplantation. An important goal was to identify physical health-related and psychosocial factors that could account for, or mediate, any association between gender and psychological distress. The sample for the present analyses was drawn from a larger cohort of 172 heart recipients and included all 28 women in the cohort plus 118 men who were matched demographically with the group of women. Detailed patient assessments were completed at 2, 7, and 12 months posttransplant. As expected, women's symptom levels were consistently higher than men's. However, while men's symptom levels in all areas declined with time posttransplant, women's distress in the area of depression initially improved but then worsened by the 12-month assessment. The distribution of episodes of MDD showed a temporal pattern of gender differences similar to that of depressive symptoms. The most important mediators of the gender-depression relationship were factors related to early posttransplant daily functional limitations: women reported more impairments in daily activities. Higher levels of such impairments, in turn, predicted subsequently higher depression levels by 12 months posttransplant. Several additional variables pertaining to transplant-related concerns and a low sense of personal mastery—while not serving as mediators—exerted their own independent effects on 12-month depression levels. The findings are relevant to the tailoring of educational and clinical interventions to the individual needs of women and men who receive heart transplants.Roberta G. Simmons, Ph.D., died on February 15, 1993, during data collection for this paper.     

Biblical authority and the not-so strange silence of Scripture about abortion.

Biblical authority is definitive for many Protestants in matters of faith and practice. The question this essay addresses is the deafening silence of this Scriptural authority on the controversial issue of abortion, especially because Christian scholars have argued vehemently against this practice. In particular, Michael Gorman's recent article 'Why is the New Testament silent about abortion?' raises many substantive issues with implications for the very meaning of authority, faith, and the life of the community. It is contended that elective abortion poses significant substantive issues with which a woman, or couple, must struggle, and that it is inappropriate (perhaps unfaithful) to make such a profound decision according to unfeeling or out-modeled patriarchal rules.     

The effect of asymmetrical sample training on retention functions for hedonic samples in rats

Rats were trained in a symbolic delayed matching-to-sample task to discriminate sample stimuli that consisted of the presence of food or the absence of food. Asymmetrical sample training was provided in which one group was initially trained with only the food sample and the other group was initially trained with only the no-food sample. In addition, within each group half of the rats were trained with an illuminated intertrial interval (ITI) and the remaining rats with a dark ITI. While the retention functions did not differ as a function of which sample was trained first, they did differ as a function of the similarity in the illumination conditions during the ITI and the delay interval. Symmetrical retention functions were obtained when the lighting conditions were similar and slightly asymmetrical retention functions were obtained when the lighting conditions were dissimilar. Probe tests confirmed that features of the no-food sample were attended to and used to generate a memory representation for the no-food sample. The results are not consistent with the hypothesis that asymmetrical sample training encourages coding of the sample introduced initially and default responding to the subsequently introduced sample. Rats generate memory representations for both samples when asymmetrical sample training is given with hedonic samples.     

Parental Behaviors During Family Interactions Predict Changes in Depression and Anxiety Symptoms During Adolescence

This study investigated the prospective, longitudinal relations between parental behaviors observed during parent-adolescent interactions, and the development of depression and anxiety symptoms in a community-based sample of 194 adolescents. Positive and negative parental behaviors were examined, with negative behaviors operationalized to distinguish between observed parental expressions of aggression and dysphoria. Results showed that higher levels of parental aggression prospectively predicted higher levels of both depression and anxiety symptoms in adolescents over two-and-a-half years, whereas higher levels of positive parental behaviors prospectively predicted lower levels of depression symptoms only. Parental dysphoric behavior was not related to changes in either symptom dimension. These results suggest that patterns of parental behaviors may be differentially associated with depressive versus anxious outcomes in adolescents, and highlight the potential role for family-focused prevention or treatment interventions aimed at reducing an escalation of depression and anxiety symptoms in adolescence.