Dual-goal facilitation in Wason's 2-4-6 task: what mediates successful rule discovery?

The standard 2-4-6 task requires discovery of a single rule and produces success rates of about 20%, whereas the dual-goal (DG) version requests discovery of two complementary rules and elevates success to over 60%. The experiment examined two explanations of DG superiority: Evans' (1989) positivity-bias account, and Wharton, Cheng, and Wickens' (1993) goal-complementarity theory. Two DG conditions were employed that varied the linguistic labelling of rules (either positively labelled Dax vs. Med, or mixed-valence “fits” vs. “does not fit”). Solution-success results supported the goal-complementarity theory since facilitation arose in both DG conditions relative to single-goal tasks, irrespective of the linguistic labelling of hypotheses. DG instructions also altered quantitative and qualitative aspects of hypothesis-testing behaviour, and analyses revealed the novel result that the production of at least a single descending triple mediates between DG instructions and task success. We propose that the identification of an appropriate contrast class that delimits the scope of complementary rules may be facilitated through the generation of a descending instance. Overall, our findings can best be accommodated by Oaksford and Chater's (1994) iterative counterfactual model of hypotheses testing, which can readily subsume key elements of the goal-complementarity theory.     

PTSD and substance-related problems: the mediating roles of disconstraint and negative emotionality

The authors examined competing hypotheses regarding the role of 2 personality dimensions, disconstraint and negative emotionality, in mediating the relationship between posttraumatic stress disorder (PTSD) severity and substance-related problems. Data were drawn from a large sample of male Vietnam veterans. The best-fitting structural model included significant indirect paths from PTSD to both alcohol- and drug-related outcomes through disconstraint, and a significant indirect path from PTSD to alcohol-related problems through negative emotionality. There were no direct effects of PTSD on either substance-related outcome. These findings indicate distinct pathways to different forms of substance-related problems in PTSD and underscore the role of personality in mediating these relationships.     

Romantic involvement often reduces men's testosterone levels--but not always: the moderating role of extrapair sexual interest

Testosterone (T) appears to facilitate what biologists refer to as mating effort--the investment of time and energy into same-sex competition and mate-seeking behavior. Multiple studies show that men who are romantically involved (i.e., are paired) have lower T than single men, which may be due to a facultative adjustment by men of T levels in response to lower demands for mating effort. The authors proceeded on the basis of the idea that men who retain interests in sexual opportunities with women other than a primary partner continue to dedicate more time and energy to mating effort when romantically paired, and so they predicted that the association between relationship status and T depends on men's extrapair sexual interests. Study 1 used the Sociosexual Orientation Inventory to measure extrapair sexual interests, whereas Study 2 used a broader measure to examine this interaction. Both studies found support for it. These results have implications for an understanding of the biosocial regulation of men's behavior in romantic relationships.     

The latent structure of posttraumatic stress disorder: a taxometric investigation of reactions to extreme stress

Mental health professionals have debated whether posttraumatic stress disorder (PTSD) can be qualitatively distinguished from normal reactions to traumatic events. This debate has been fueled by indications that many trauma-exposed individuals evidence partial presentations of PTSD that are associated with significant impairment and help-seeking behavior. The authors examined the latent structure of PTSD in a large sample of male combat veterans. Three taxometric procedures-MAMBAC, MAXEIG, and L-Mode-were performed with 3 indicator sets drawn from a clinical interview and a self-report measure of PTSD. Results across procedures, consistency tests, and analysis of simulated comparison data all converged on a dimensional solution, suggesting that PTSD reflects the upper end of a stress-response continuum rather than a discrete clinical syndrome.     

Linked lives: the intergenerational transmission of antisocial behavior

There is a strong assumption of intergenerational continuity in behavior patterns, including antisocial behavior. Using a 3-generation, prospective study design, we examine the level of behavioral continuity between Generation 2 (G2) and Generation 3 (G3), and the role of economic disadvantage and parenting behaviors as mediating links. We estimate separate models for G2 fathers and G2 mothers. Data are drawn from the Rochester Youth Development Study, a longitudinal study begun in 1988 during G2's early adolescence (n = 1,000), which has collected prospective data on G2, their parents (G1), and now their G3 children. Results show that intergenerational continuity in antisocial behavior is evident, albeit somewhat modest. Parenting styles and financial stress do play a mediating role, although their effects vary by G2's gender. In general, adolescent delinquency plays a larger role in linking the generations for G2 fathers, whereas parenting behaviors and financial stress play a larger role for G2 mothers.     

Menstrual expressions and menstrual attitudes

Women's responses to a questionnaire survey in a Northeastern U.S. college community are examined to determine whether usage preferences in menstrual expressions are systematically related to reported attitudes towards menstruation. While those women who use expressions with negative connotations tend to report negative attitudes, the converse is not true. A striking contrast is noted between familiarity and use of menstrual expressions and, in general, menstrual expressions are not consistently associated with or reflective of menstrual attitudes.     

The relationship of target and response complexity in coincident timing performance

This paper reports two experiments concerned with the interaction of response and target factors in a coincident timing situation. Coincident timing involves executing a response to intercept a moving target. The target response relationship was manipulated in the first experiment by providing some targets with no structure (linear path) and others containing 1 and 2 bounce points. In the second experiment, responses required 0, 1, or 2 reversals in direction. The results provide tentative support for the notion that structure in the target path could be linked to the key temporal response dynamics for improved performance consistency, and that subjects may alter their response structure to incorporate this linkage. This can be further extended to the advantage of simply moving while perceiving movement. This paper stresses the importance of examining the perceptual and motor requirements of the coincident timing skill in unison.     

Comorbidity In Post-Traumatic Stress Disorder An Analysis of Community and Clinical Studies1

Post-traumatic stress disorder (PTSD) is alleged to be associated with high rates of concurrent psychological disorders. This paper considers the available literature regarding comorbidity in PTSD and reviews in detail the findings to date. This critical evaluation includes studies of clinical samples, veterans community surveys, and population surveys. It also presents new data drawn from 50 PTSD cases assessed at the Boston PTSD Center using a comprehensive, multidimensional diagnostic procedure. The data firmly support the notion that PTSD, regardless of the nature of the trauma, is associated with high rates of other major psychological disorders including substance abuse, major depression, and personality disorders. Despite these findings the issue of cause and effect surrounding comorbidity remains open at this time. More research is needed to determine if exposure to extreme stressors in fact produces the broad spectrum of psychopathology suggested by individuals with PTSD or whether individuals with intrinsic vulnerability are more likely to develop PTSD when exposed to extreme stressors. Implications of the findings from this review are discussed with respect to concepts in diagnosis and comorbidity.