Prior knowledge enhances the category dimensionality effect

A study of the combined influence of prior knowledge and stimulus dimensionality on category learning was conducted. Subjects learned category structures with the same number of necessary dimensions but with more or fewer additional, redundant dimensions and with either knowledge-related or knowledge-unrelated features. Minimal-learning models predict that all subjects, regardless of condition, either should learn the same number of dimensions or should respond more slowly to each dimension. Despite similar learning rates and response times, subjects learned more features in the high-dimensional than in the low-dimensional condition. Furthermore, prior knowledge interacted with dimensionality, increasing what was learned, especially in the high-dimensional case. A second experiment confirmed that the participants did, in fact, learn more features during the training phase, rather than simply inferring them at test. These effects can be explained by direct associations among features (representing prior knowledge), combined with feedback between features and the category label, as was shown by simulations of the knowledge resonance, or KRES, model of category learning.     

Acquired flavour preferences: contextual control of adaptation-level effects

This experiment investigated the role of context in the expression of conditioned flavour preferences. Rats were trained on a mixture of almond and sucrose and were then given intermixed exposures to almond in one context (Context A) and to sucrose in a second context (Context S). Finally, choice tests were given in both contexts, with one group given almond-versus-water tests and the other almond + sucrose-versus-sucrose tests. Preference for almond over water was greater in Context A than in Context S. Conversely, preference for almond + sucrose over sucrose was greater in Context S than in Context A. These results suggest that the perceived sweetness of a flavour depends on the context in which it is presented and confirm that expression of a flavour preference depends on the type of test employed.     

Randomized, controlled trial of Behavioral Family Systems Therapy for Diabetes: maintenance and generalization of effects on parent-adolescent communication

We report a randomized trial of a revised Behavioral Family Systems Therapy for Diabetes (BFST-D) intervention. Families of 104 adolescents with diabetes were randomized to standard care (SC) or to 6 months of an educational support group (ES) or BFST-D. Family communication and problem-solving skills were assessed at 0, 6, 12, and 18 months by independent rating of videotaped family problem-solving discussions. BFST-D improved individual communication of adolescents and mothers, but not fathers. BFST-D significantly improved quality of family interaction compared to SC (10 of 12 comparisons) and ES (6 of 12 comparisons). Changes in family communication were differentially associated with changes in glycemic control, adherence, and family conflict. BFST-D improved family communication and problem solving relative to SC and modestly relative to ES.     

The effects of choice on intrinsic motivation and related outcomes: a meta-analysis of research findings

A meta-analysis of 41 studies examined the effect of choice on intrinsic motivation and related outcomes in a variety of settings with both child and adult samples. Results indicated that providing choice enhanced intrinsic motivation, effort, task performance, and perceived competence, among other outcomes. Moderator tests revealed the effect of choice on intrinsic motivation was stronger (a) for instructionally irrelevant choices compared to choices made between activities, versions of a task, rewards, and instructionally relevant options, (b) when 2 to 4 successive choices were given, (c) when rewards were not given after the choice manipulation, (d) when participants given choice were compared to the most controlling forms of control groups, (e) for children compared to adults, (f) for designs that yoked choice and control conditions compared to matched designs in which choice was reduced or designs in which nonyoked, nonmatched controls were used, and (g) when the experiment was conducted in a laboratory embedded in a natural setting. Implications for future research and applications to real-world settings are discussed.     

New job market entrants' future work self,career adaptability and job search outcomes: Examining mediating and moderating models

Based on career construction theory and the model of proactive motivation, the current research examined the mediating and moderating models for the relations among future work self, career adaptability, job search self-efficacy and employment status. A survey study was conducted among Chinese university graduates (N = 270). The results showed that future work self (measured at wave 1) had positive effect on employment status (measured at wave 3), with this relationship partially mediated by career adaptability (measured at wave 1) and job search self-efficacy (measured at wave 2). In addition, the results further revealed that the positive effect of future work self on job search self-efficacy was stronger among the graduates who had a higher level of career adaptability. In support of the hypothesized moderated mediation model, for individuals with a higher level of career adaptability, the indirect effect of future work self on employment status through job search self-efficacy was stronger. These findings carry implications for research on job search behavior, career education and career counseling.     

An evaluation of crisis hotline outcomes. Part 1: Nonsuicidal crisis callers

The effectiveness of telephone crisis services/hotlines, examining proximal outcomes as measured by changes in callers' crisis state from the beginning to the end of their calls to eight centers in the U.S. and intermediate outcomes within 3 weeks of their calls, was evaluated. Between March 2003 and July 2004, 1,617 crisis callers were assessed during their calls and 801 (49.5%) participated in the followup assessment. Significant decreases in callers' crisis states and hopelessness were found during the course of the telephone session, with continuing decreases in crisis states and hopelessness in the following weeks. A majority of callers were provided with referrals and/or plans of actions for their concerns and approximately one third of those provided with mental health referrals had followed up with the referral by the time of the follow-up assessment. While crisis service staff coded these callers as nonsuicidal, at follow-up nearly 12% of them reported having suicidal thoughts either during or since their call to the center. The need to conduct suicide risk assessments with crisis callers and to identify strategies to improve referral follow-up is highlighted.     

Coercive and precocious sexuality as a fundamental aspect of psychopathy

Sexual behavior is closely associated with delinquency and crime. Although psychopaths, by definition, have many short-term sexual relationships, it has not been shown that sexuality is a core aspect of psychopathy. A Darwinian view of psychopathy led to the hypothesis that psychopaths have a unique sexuality involving early, frequent, and coercive sex. Our subjects were 512 sex offenders assessed on the Hare Psychopathy Checklist (PCL-R). Five variables reflecting early, frequent, and coercive sex loaded on the same principal component in exploratory factor analysis on a subset of the sample, whereas PCL-R items pertaining to adult sexual behavior did not. Confirmatory factor analysis of the remaining subjects yielded a measurement model containing three inter-correlated factors - the traditional two PCL-R factors, and coercive and precocious sexuality. Taxometric analyses gave evidence of a natural discontinuity underlying coercive and precocious sexuality. Coercive and precocious sexuality yielded statistically significant associations with other study variables predicted by the Darwinian hypothesis. The present findings are consistent with prior empirical findings and support the hypothesis that psychopathy has been a nonpathological, reproductively viable, alternate life history strategy.     

Cumulative risk, maternal responsiveness, and allostatic load among young adolescents

The purpose of this study was to examine the impact of cumulative risk exposure in concert with maternal responsiveness on physiological indicators of chronic stress in children and youth. Middle-school children exposed to greater accumulated psychosocial (e.g., family turmoil, poverty) and physical (e.g., crowding, substandard housing) risk factors manifested higher levels of allostatic load, a physiological marker of cumulative wear and tear on the body caused by the mobilization of multiple, physiological response systems. This effect was longitudinal, residualizing allostatic load 3-4 years earlier when the youth were in elementary school. This effect, however, occurred only among adolescents with mothers low in responsiveness. Cumulative risk was also associated with dynamic cardiovascular processes in response to an acute stressor (mental arithmetic). Higher risk was associated with muted reactivity and slower, less efficient recovery in blood pressure. These dynamic cardiovascular effects occurred irrespective of maternal responsiveness.