Dissimilarity is used as evidence of category membership in multidimensional perceptual categorization: a test of the similarity-dissimilarity generalized context model

In exemplar models of categorization, the similarity between an exemplar and category members constitutes evidence that the exemplar belongs to the category. We test the possibility that the dissimilarity to members of competing categories also contributes to this evidence. Data were collected from two 2-dimensional perceptual categorization experiments, one with lines varying in orientation and length and the other with coloured patches varying in saturation and brightness. Model fits of the similarity-dissimilarity generalized context model were used to compare a model where only similarity was used with a model where both similarity and dissimilarity were used. For the majority of participants the similarity-dissimilarity model provided both a significantly better fit and better generalization, suggesting that people do also use dissimilarity as evidence.     

Posttraumatic stress symptoms following childbirth and mothers' perceptions of their infants

Postpartum psychological distress can adversely affect the early mother–infant relationship; however, this has not been investigated in relation to posttraumatic stress disorder (PTSD) following childbirth. This article explores whether PTSD symptoms relating to labor and delivery are associated with mothers' early perceptions of their infant. Using labor and childbirth as the stressor criterion, 211 women were assessed at 6 weeks' postpartum for symptoms of intrusions, avoidance, and hyperarousal. Their perceptions of their infants, of mother‐to‐infant attachment, and infant behavioral characteristics also were evaluated. In sum, 3.8% of the women fulfilled full diagnostic criteria, and a further 21.3% reported clinically significant symptoms on at least one dimension of PTSD. Those meeting full or partial criteria perceived their attachment relationships to be significantly less optimal and reported more negative maternal representations in terms of their infants being less warm and more invasive. They also rated them as being temperamentally more difficult, prone to distress, and less easy to soothe. However, when the effects of depression were partialled, only the effect for perceived warmth remained. Posttraumatic stress symptoms relating to labor and delivery may adversely influence maternal perceptions of infants, with potentially adverse implications for the developing mother–infant relationship. The overlap with depressive symptoms requires further exploration.     

The development of the Body Morph Assessment version 2.0 (BMA 2.0): Tests of reliability and validity

This study tested the psychometric characteristics of the Body Morph Assessment version 2.0 (BMA 2.0). A sample of 563 adults composed of four groups classified by gender and ethnicity (Caucasian men and women and African-American men and women) were studied. Support for the internal consistency and test–retest reliability of the BMA 2.0 was found for both men and women. A study of convergent validity was conducted. The BMA 2.0 was found to have adequate reliability and validity. Norms were established for the BMA 2.0 estimates of current body size (CBS), ideal body size (IBS), and acceptable body size (ABS) for Caucasian and African-American men and women. In summary, the BMA 2.0 is a reliable and valid computerized measure of CBS, IBS, ABS, the CBS–IBS discrepancy (body dissatisfaction), and provides an estimate of over/underestimation of body size as compared to individuals of the same sex and body mass index.     

Relative reinforcing effects of different oral ethanol doses in rhesus monkeys

The relative reinforcing effects of different doses of orally delivered ethanol were evaluated. Mouth-contact responding by rhesus monkeys was measured under concurrent fixed-ratio fixed-ratio schedules of liquid delivery (0.67 ml/delivery) from each of two spouts during daily 3-hr sessions. Experiment 1 examined persistence of responding with ethanol (2%, 8%, and 32% wt/vol) and water available. When fixed-ratio values from 8 to 128 were tested, the number of ethanol deliveries obtained per session decreased as the response requirement increased. The decrease in deliveries was less at higher than at lower ethanol concentrations, however. Experiment 2 examined choice between two ethanol concentrations under concurrent fixed-ratio 16 schedules (4% vs. 8%, 4% vs. 16%, 8% vs. 16%, 2% vs. 8%, 2% vs. 32%, 8% vs. 32%). Higher concentrations (16%, 32%) generally maintained more responding than concurrently available concentrations of 8% or less. An exception was the observation of a preference for 8% over 32% ethanol. When the fixed-ratio value was increased, however, the relative preference for these two doses was reversed so that 32% ethanol maintained more responding than 8% ethanol. Thus, the direction of the preference depended on the size of the response requirement. These results indicate that the reinforcing effects of ethanol increase with dose.     

Intersectional Identities,Identity Dimensions,and Academic Contingencies of Self-Worth

Many people rely on academic performance as an important part of their self-concept, or have academic contingencies of self-worth. We compared academic contingencies of self-worth in three groups of participants, who varied in their feelings about two minority identities: sexual minority Asian/Pacific Islanders, straight Asian/Pacific Islanders, and sexual minority Whites. Comparing pairs of groups that shared one marginalized social identity, we confirmed our hypothesis that participants’ feelings about their racial identity related to contingent self-worth differently based on their sexuality; in contrast, participants’ feelings about their sexual identity related to contingent self-worth in the same way regardless of race. The group defined by the intersection of two minority social identities (Asian/Pacific Islander and sexual minority) is of particular interest.     

Entrevista con Klaus R. Scherer

RESUMEN

El profesor Scherer es uno de los Psicólogos Sociales más importantes de la actualidad, un importante investigador en temas de psicoacústica o de la conducta no verbal no vocal (como a él le gusta llamar a su campo). La contribución del profesor Scherer a la investigación del análisis psicológico de la voz y de las relaciones entre personalidad y los sitemas vocales no verbales de la comunicación ha sido muy importante para el desarrollo de la investigación en la dimensión no-verbal de la conducta. En esta entrevista Scherer reflexiona sobre el pasado y presente de la psicología alemana, refleja los hitos principales de su área de estudio y plantea el problema de la responsabilidad del investigador en la aplicación de sus hallazgos y productos. Se presenta, en esta entrevista, un ejemplo esclarecedor de la importancia de los factores interdisciplinarios en la génesis y apertura de nuevas áreas para la investigación.     

A Structural Equation Analysis of the Wide Range Assessment of Memory and Learning in a Clinical Sample

A maximum likelihood confirmatory factor analysis was performed by applying LISREL VII to the Wide Range Assessment of Memory and Learning (WRAML) in a clinical sample (N = 271). Analyses were designed to determine which of 10 hypothesized oblique factor solutions could best explain memory as measured by the WRAML. Competing latent variable models were identified in previous studies and monographs on memory. Findings supported a three-factor model including Verbal Memory, Visual Memory, and Attention/Concentration factors. Our results are consistent with previous studies suggesting that attention is an important component of memory as measured by the WRAML. This study replicates previous research in which the Learning Index was not empirically supported.