Optimism and pessimism in the context of health: bipolar opposites or separate constructs?

One difficulty plaguing research on dispositional optimism and health is whether optimism and pessimism are bipolar opposites or constitute distinct constructs. The present study examined the Life Orientation Test to determine whether the two-factor structure is explained by method bias (due to measurement) or substantive differences. The authors compared three measurement models: bipolar, bivariate, and method artifact. Optimism and pessimism emerged as distinct constructs due to substantive differences. The authors also considered the validity of optimism and pessimism, examining their relations with psychological and physical health outcomes. Optimism and pessimism were more similar in relation to psychological health than to other health-related behavior or physical health outcomes. However, a strongly interpretable pattern for the relation of optimism and pessimism to the health outcomes did not emerge. Further research may benefit from considering optimism and pessimism as bivariate and also should consider the conceptual components and behavioral mechanisms specific to each variable.     

Western scrub-jays (<Emphasis Type="Italic">Aphelocoma californica</Emphasis>) use cognitive strategies to protect their caches from thieving conspecifics

Food caching birds hide food and recover the caches when supplies are less abundant. There is, however, a risk to this strategy because the caches are susceptible to pilfering by others. Corvids use a number of different strategies to reduce possible cache theft. Scrub-jays with previous experience of pilfering other's caches cached worms in two visuospatially distinct caching trays either in private or in the presence of a conspecific. When these storers had cached in private, they subsequently observed both trays out of reach of a conspecific. When these storers had cached in the presence of a conspecific, they subsequently watched the observer pilfering from one of the trays while the other tray was placed in full view, but out of reach. The storers were then allowed to recover the remaining caches 3 h later. Jays cached more worms when they were observed during caching. At the time of recovery, they re-cached more than if they had cached in private, selectively re-caching outside of the trays in sites unbeknown to potential thieves. In addition, after a single pilfering trial, the jays switched their recovery strategy from predominantly checking their caches (i.e. returning to a cache site to see whether the food remained there) to predominantly eating them. Re-caching remained constant across the three trials. These results suggest that scrub-jays use flexible, cognitive caching and recovery strategies to aid in reducing potential future pilfering of caches by conspecifics.     

Pretty in Ink: Conformity,Resistance, and Negotiation in Women's Tattooing

Since the early 1990s, Canadian women have participated in tattooing in unprecedented numbers. These women are utilizing tattoo body projects (C. Shilling, 1993) to communicate a wide range of personal and cultural messages, and challenging the long-standing association between tattooing and masculinity. However, and perhaps more consequentially, women's tattoo projects express diverse sensibilities about femininity and the feminine body. For some Canadian women, contesting culturally established (N. Elias & J. Scotson, 1965) constructions of the female body is central in their tattoo body projects, whereas others participate in tattooing as an explicit form of consent to such constructions. In this paper, women's tattooing activities and their subsequent tattoo narratives are critically inspected as deeply gendered practices and discourses. I present participant observation and interview data on tattoo enthusiasm in Canada. The focus is directed toward the ways in which conformity to, resistance against, and the negotiation of established cultural ideas about femininity are equally embedded in women's tattooing. Drawing upon feminist theories about bodies (cf. S. Bordo, 1990; K. Davis, 1994; J. Price & M. Shildrick, 1999; S. Williams & G. Bendelow, 1998) and central tenets of process-sociology (N. Elias, 1991, 1994, 1996; N. Elias & J. Scotson, 1965), emphasis is given to how women employ tattooing as a communicative signifier of established and outsider constructions of femininity.     

Fimbria-fornix lesions disrupt the dead reckoning (homing) component of exploratory behavior in mice

Exploration is the primary way in which rodents gather information about their spatial surroundings. Thus, spatial theories propose that damage to the hippocampus, a structure thought to play a fundamental role in spatial behavior, should disrupt exploration. Exploration in rats is organized. The animals create home bases that are central to exploratory excursions and returns, and hippocampal formation damage alters the organization of exploration by disrupting returns. Mice do not appear to readily establish home bases in novel environments, thus, for this species, it is more difficult to establish the contribution of the hippocampus to exploration. The purpose of the present study was threefold: develop a task in which mice center their exploration from a home base, determine whether the exploratory behavior is organized, and evaluate the role of fimbria-fornix lesions on exploration. Mice were given a novel exploratory task in which their nesting material was placed on a large circular table. Video records of control and fimbria-fornix mice were made in both light and dark (infrared light) conditions. Exploration patterns (outward trips, stops, and homeward trips) were reconstructed from the video records. Control mice centered their activity on their bedding, from which they made circuitous outward trips marked by many stops, and periodic direct returns. The bedding-centered behavior and outward trips of the fimbria-fornix mice were similar to those of the control mice, but significantly fewer direct return trips occurred. The direct homeward trips observed under light and dark conditions were consistent with a dead-reckoning strategy, in which an animal computes its present position and homeward trajectory from self-movement cues generated on the outward trip. Because the fimbria-fornix lesions disrupted the homeward component of exploratory trips, we conclude that the fimbria-fornix may contribute to dead reckoning in mice. The results also show that the home-bedding methodology facilitates the establishment of a home base by mice, thus providing a useful methodology for studies with mice.     

Role of dopamine,the frontal cortex and memory circuits in drug addiction: insight from imaging studies

Drug addiction is characterized by a set of recurring processes (intoxication, withdrawal, craving) that lead to the relapsing nature of the disorder. We have used positron emission tomography to investigate in humans the role of dopamine (DA) and the brain circuits it regulates in these processes. We have shown that increases in DA are associated with the subjective reports of drug reinforcement corroborating the relevance of drug-induced DA increases in the rewarding effects of drugs in humans. During withdrawal we have shown in drug abusers significant reductions in DA D2 receptors and in DA release. We postulate that this hypodopaminergic state would result in a decreased sensitivity to natural reinforcers perpetuating the use of the drug as a means to compensate for this deficit and contributing to the anhedonia and dysphoria seen during withdrawal. Because the D2 reductions are associated with decreased activity in the anterior cingulate gyrus and in the orbitofrontal cortex we postulate that this is one of the mechanisms by which DA disruption leads to compulsive drug administration and the lack of control over drug intake in the drug-addicted individual. This is supported by studies showing that during craving these frontal regions become hyperactive in proportion to the intensity of the craving. Craving is also associated with activation of memory circuits including the amygdala (implicated in conditioned learning), hippocampus (implicated in declarative learning), and dorsal striatum (implicated in habit learning) all of which receive DA innervation. We therefore postulate that dopamine contributes to addiction by disrupting the frontal cortical circuits that regulate motivation, drive, and self-control and by memory circuits that increase the motivational salience of the drug and drug-associated stimuli.     

The role of diverse instruction in conceptual change

This study examined how a fundamental principle of induction and scientific reasoning, information diversity, could be used to promote change in children's mental models of the earth's shape. Six-year-old children (N=132) were randomly allocated to a control or to one of two training conditions. Some training groups received instruction that simultaneously challenged children's beliefs concerning (a) why the earth appears flat to a surface observer and (b) the role of gravity. Others received instruction that repeatedly challenged only one of these beliefs. An adaptation of the Vosniadou and Brewer (1992, Cognitive Psychology 24, 535-585) protocol for identifying mental models of the earth was administered before and after instruction. Both instruction methods produced increases in factual knowledge. Only children receiving instruction about two core beliefs, however, showed an increased rate of acceptance of a spherical earth model at posttest. The findings show that instruction that challenges diverse aspects of children's na?ve scientific beliefs is more likely to produce conceptual change.     

Executive functioning as a potential mediator of age-related cognitive decline in normal adults

Critical requirements for the hypothesis that executive functioning is a potential mediator of age-related effects on cognitive functioning are that variables assumed to reflect executive functioning represent a distinct construct and that age-related effects on other types of cognitive functioning are reduced when measures of executive functioning are statistically controlled. These issues were investigated in a study involving 261 adults between 18 and 84 years of age. Although age-related effects on various cognitive abilities were substantially reduced after statistical control of the variance in measures hypothesized to represent executive functioning, there was only weak evidence for the existence of distinct constructs corresponding to executive functioning or to aspects of executive control concerned with inhibition, updating, or time sharing.     

The social reality of the imaginary audience: a grounded theory approach

Traditional approaches to understanding the imaginary audience are challenged in this study. Three hundred sixty-one British schoolchildren (aged 14 and 15 years) were asked to express their worries and concerns, using grounded theory methodology. Qualitative responses were collated and coded according to emerging categories, with "what other people think" identified as the central concern. In particular, the findings are used to critique Elkind's (1967) theory of adolescent egocentrism. Data presented in this study suggest that adolescents worry about what other people think because there are real personal and social consequences. Such concerns are seen as being based in social reality and are not imaginary as Elkind suggested. In conclusion, new methodologies which place young people at the center of the analysis are advocated.     

Child-parent attachment and children's peer relations: a quantitative review

The central premise of attachment theory is that the security of the early child-parent bond is reflected in the child's interpersonal relationships across the life span. This meta-analysis was based on 63 studies that reported correlations between child-parent attachment and children's peer relations. The overall effect size (ES) for child-mother attachment was in the small-to-moderate range and was quite homogeneous. ESs were similar in studies that featured the Strange Situation and Q-sort methods. The effects were larger for peer relations in middle childhood and adolescence than for peer relations in early childhood. ESs were also higher for studies that focused on children's close friendships rather than on relations with other peers. Gender and cultural differences in ESs were minimal. The results for the few studies on father-child attachment were inconclusive.     

Design and development of the European American values scale for Asian Americans

Existing instruments for measuring Asian American acculturation emphasize behavior acculturation to the exclusion of value acculturation. Most are based on the assumption that acquisition of European American behavior occurs simultaneously with the loss of Asian behavior. With the advent of the Asian Values Scale (AVS; B.S.K. Kim, D.R. Atkinson, & P.H. Yang, 1999), it is now possible to assess adherence to Asian cultural values. This article describes the development of a scale that can be used to measure Asian American adherence to European American values. The current scale, combined with the AVS, can be used to independently measure Asian American acculturation to European American values and enculturation in Asian values.