Neural correlates of variable working memory load across adult age and skill: dissociative patterns within the fronto-parietal network

We examined neural changes related to variations in working memory load by using an n -back task with three levels and functional magnetic resonance imaging. Younger adults were divided into high- and low-performing groups (Young-High; Young-Low) and compared with older adults. Relative to Young-High, capacity-constraints in working memory were apparent between load 1–2 for the elderly and between load 2–3 for Young-Low. Capacity-constraints in neural activity followed this pattern by showing a monotonically increasing response in parietal cortex and thalamus for Young-High, whereas activity leveled off at 1-back for the elderly and at 2-back for Young-Low. The response in dorsal frontal cortex followed a similar pattern with the addition that the magnitude of activation differed within capacity limitations (Old > Young at 1-back; Young-Low > Young-High at 2-back). These findings indicate that an important determinant of WM capacity is the ability to keep the frontal cortex adequately engaged in relation to current task demands.     

Toddlers can adaptively change how they categorize: same objects,same session,two different categorical distinctions

Two experiments demonstrate that 14‐ to 18‐month‐old toddlers can adaptively change how they categorize a set of objects within a single session, and that this ability is related to vocabulary size. In both experiments, toddlers were presented with a sequential touching task with objects that could be categorized either according to some perceptually salient dimension corresponding to a taxonomic distinction (e.g. animals vs. vehicles) or to some less obvious dimension (e.g. rigid vs. deformable). In each experiment, children with larger productive vocabularies responded to both dimensions, showing evidence of sensitivity to each way of categorizing the items. Children with smaller productive vocabularies attended only to the taxonomically related categorical grouping. These experiments confirm that toddlers can adaptively shift the basis of their categorization and highlight the dynamic interaction between the child and the current task in early categorization.     

Token Majority: The Work Attitudes of Male Flight Attendants

This study examined the work experiences of men, a traditional workplace majority, as minority members of a female-dominated occupation. We used tokenism and social categorization theories to propose and test a set of hypotheses that link token status (a less than 15% minority) with male flight attendants' work attitudes through intervening psychological and job factors. Survey data from a sample of 236 male and female flight attendants supported a model in which a negative relationship between token status and the work attitudes of job satisfaction and organizational attachment was mediated by low self-esteem, increased role ambiguity, and poor job fit. The uncovering of these previously unmeasured intervening variables strengthens theoretical connections between demography and work outcomes and suggests leverage points for improving the work attitudes of individuals in the minority.     

Sidman avoidance in the fish

Goldfish trained in a shuttle box under conditions in which changing compartments postponed shock for 20 sec showed a substantial, negatively accelerated increase in rate of crossing. That the avoidance-contingency was responsible for the change in behavior is suggested by the fact that no significant increase in rate of crossing appeared in control animals which were paired with the experimentals and shocked whenever the experimental animals were shocked; there is some evidence, indeed, that the control animals were handicapped in their subsequent adjustment to the avoidance condition. The introduction of a warning stimulus (light) in the last 5 sec of the response-shock interval decreased the rate of crossing in the first 15 sec and increased the rate of crossing in the last 5 sec. Reducing the shock-shock interval from 20 sec to 2.5 sec had no marked effect. The results are compared with those obtained in analogous experiments with higher animals.     

Adolescents' Reward‐related Neural Activation: Links to Thoughts of Nonsuicidal Self‐Injury

Adolescence is a critical developmental period marked by an increase in risk behaviors, including nonsuicidal self‐injury (NSSI). Heightened reward‐related brain activation and relatively limited recruitment of prefrontal regions contribute to the initiation of risky behaviors in adolescence. However, neural reward processing has not been examined among adolescents who are at risk for future engagement for NSSI specifically, but who have yet to actually engage in this behavior. In the current fMRI study (N = 71), we hypothesized that altered reward processing would be associated with adolescents' thoughts of NSSI. Results showed that NSSI youth exhibited heightened activation in the bilateral putamen in response to a monetary reward. This pattern of findings suggests that heightened neural sensitivity to reward is associated with thoughts of NSSI in early adolescence. Implications for prevention are discussed.     

A longitudinal investigation of stress spillover in marriage: does spousal support adequacy buffer the effects?

Stress spillover in marriage was examined within a stress-buffering conceptual framework in a multiwave, longitudinal sample of newlywed husbands and wives (N = 101 couples). Spousal support, chronic role strain, and marital satisfaction were assessed 4 times over 3 years and analyzed via actor-partner interdependence model and growth curve analytic techniques. Greater escalation in husbands' role strain over the first 3 years of marriage was associated with steeper declines in their marital satisfaction regardless of the adequacy of spousal support provided by their wives. In contrast, greater escalation in husbands' and wives' role strain was associated with significantly less marital decline for wives, and these links were bolstered when husbands provided wives with more adequate support. The present study is one of the first to explicate the underlying processes through which role strain and spousal support facilitate and mitigate the developmental course of marital satisfaction.