Comparing black-capped (Poecile atricapillus) and mountain chickadees (Poecile gambeli): use of geometric and featural information in a spatial orientation task

Since Cheng (Cognition 23:149–178, 1986) first proposed the “geometric module” in rats, a great deal of research has focused on how other species use geometric information and how geometric encoding may differ across species. Here, hand-reared and wild-caught black-capped chickadees and wild-caught mountain chickadees searched for food hidden in one corner in a rectangular environment. Previous research has shown that mountain chickadees do not spontaneously encode geometric information when a salient feature is present near the goal location. Using a slightly different training and testing procedure, we found that both hand-reared and wild-caught black-capped chickadees encoded geometric information, even in the presence of a salient landmark. Some, but not all, mountain chickadees also encoded geometric information. Overall, our results suggest that use of geometric information may be a less preferred strategy for mountain chickadees than for either wild-caught or hand-reared black-capped chickadees. To our knowledge, this is the first direct interspecies comparison of use of geometric information in a spatial orientation task.     

Gender differences in the relationships of cardiovascular symptoms and somatosensory amplification to mortality

Symptoms of angina and dyspnea predict coronary artery disease and death less well in women than in men. Greater somatosensory amplification - a psychosocial propensity to report symptoms of physical discomfort - may lead women to report relatively high levels of angina and dyspnea for reasons unrelated to coronary disease, reducing their associations with mortality. We assessed this hypothesis in a nationally representative survey of U.S. adults. When stratified by gender, angina and dyspnea significantly predicted mortality among men, but predicted it less well among women. After adjusting for amplification, cardiovascular symptoms did not predict mortality among women, but amplification was positively associated with mortality among older women.     

Sex ratio and mate preferences: a cross‐cultural investigation

Sex ratio is the number of men per 100 reproductive‐age women within a specified mating pool. We generated and tested two hypotheses about the cross‐cultural relationships between sex ratio and mate preferences using preference ratings of 18 characteristics provided by 9809 participants and corresponding sex ratio data secured from an international organization. The Classical Sex Ratio Mate Preference Shifts Hypothesis predicts that in imbalanced sex ratio societies, the more numerous sex will lower their standards, to facilitate acquisition of a partner of the less numerous sex. The Alternative Sex Ratio Mate Preference Shifts Hypothesis predicts that in lower sex ratio societies, men will lower their standards to secure more short‐term matings, whereas women will raise their standards to avoid deception by men seeking short‐term relationships. Results supported the Classical Sex Ratio Mate Preference Shifts Hypothesis for men, and the Alternative Sex Ratio Mate Preference Shifts Hypothesis for women. Discussion addresses limitations of the current research and highlights future directions for research on the relationships between sex ratio and mating psychology and behavior. Copyright © 2006 John Wiley & Sons, Ltd.     

Impact of neighborhood disadvantage on overt behavior problems during early childhood

Researchers have yet to examine the impact of neighborhood disadvantage on early child behavior problems (BPs) longitudinally. We examined the impact of neighborhood disadvantage on overt BPs in a low-income, urban sample of 281 African American and European American boys followed longitudinally from toddlerhood to school entry. Measures included census data and maternal report of BPs, sociocultural factors, parental criminality, and maternal depressive symptomatology. After controlling for age 2 overt BPs, family selection variables, and residential instability, neighborhood effects on boys' behavior emerged, but only at age 6 and only at the extreme of neighborhood disadvantage (i.e., underclass). Findings suggest boys in underclass neighborhoods are at risk for overt BPs as they make the transition to elementary school.     

Religious Fundamentalism and Gender Differences

The role of religious fundamentalism and its relationship to shame and guilt was evaluated in 107 students who attend a church-sponsored university. A number of personality measures were given and gender differences were analyzed. The role of externalization was similar for males in this sample to that of earlier studies. However, it was found that females showed positive correlations between externalization and both shame and guilt. For females, more fundamentalistic religious training may help to contribute to an external orientation at the expense of identifying with a personal religion, and appropriate guilt.     

Memory deficits in young schizophrenics with normal general intellectual function

The aim of the present study was to examine different dimensions of memory functioning in young schizophrenics with normal general intellectual abilities. Thirty-three patients with schizophrenia and 33 healthy controls were included in the study. The results suggest that immediate short-term memory is intact, though there emerged a working memory deficit in the schizophrenia group. Deficient encoding of verbal material was observed in some, but not in other, testing conditions. There also seemed to be a retrieval deficit for verbal material in schizophrenia, though no storage deficit was indicated. Impaired memory for non-verbal material was also revealed. These results occurred in a context of intact executive functioning as measured by the Wisconsin Card Sorting Test. The results indicate that temporal and frontal structures, as well as their interconnections, may be compromised in schizophrenia.     

Testing the investment model of relationship commitment and stability in a longitudinal study of married couples

This study tested Rusbult’s (1980, 1983) investment model of relationship commitment and stability using data from both partners of 3,627 married couples. As pre-dicted, spouses’ satisfaction, investments, and quality of alternatives were unique predictors of their commitment to the marital relationship. Additionally, commitment assessed at the initial testing predicted marital termination or stability 18 months later. Multiple-group path analyses showed that the investment model provided an adequate fit to the data and that the associations among variables were similar for husbands and wives. Limitations of the model as well as directions for future research are consid-ered. This research used the American Couples, 1975-1978, data set [made accessible in 1992, computer data]. These data were collected by Philip Blumstein and Pepper Schwartz and are available through the archive of the Henry A. Murray Research Center of Radcliffe College, Cambridge, Massachusetts (Producer and Distributor). This paper is based on work supported under a National Science Foundation Graduate Fellowship awarded to Emily A. Impett and a UCLA Academic Senate Research Grant to Letitia Anne Peplau. The authors are very grateful to Kevin Kim and Jodie Ullman for statistical consulting and Brian Doss for comments on an earlier draft.