In search of the psychopathic sexuality taxon: indicator size does matter

Recent research has suggested that a qualitatively distinct subtype of psychopathic sex offender can be identified via taxometric analyses (Harris et al., 2007). In this study we attempted to replicate the hypothesized psychopathic sexuality taxon in a group of 503 male sexual offenders using data from the Psychopathy Checklist-Revised (PCL-R:Hare, 2003) and five coercive and precocious sexuality items. Ambiguous to dimensional results were obtained when, in a replication of the Harris et al. (2007) study,dichotomized indicators were analyzed with summed input maximum covariance (MAXCOV). Clearly dimensional results, however, were obtained when higher correlating and more valid quasi-continuous indicators were analyzed with traditional (input variables not summed) MAXCOV, and both dichotomous and quasi-continuous indicators were analyzed with mean above minus below a cut (MAMBAC) and latent-mode factor analysis (L-Mode). These results suggest that Harris et al. (2007) may have mistaken the random fluctuations of weakly correlating and poorly differentiating indicators for a taxon. Consistent with the vast majority of earlier research,our results suggest that psychopathy (with or without coercive and precocious sexuality) is a dimensional construct.     

Do positive children become positive adults? Evidence from a longitudinal birth cohort study

BACKGROUND: Little is known about the long-term consequences of positive wellbeing in childhood in the general population. We used the MRC National Survey of Health and Development (the British 1946 birth cohort) to test associations between adolescent positive wellbeing and social functioning in midlife. METHOD: Temperament and behaviour at ages 13 and 15 years were rated by school teachers on a range of criteria. These mostly referred to absence or presence of conduct and emotional problems, but four items allowed positive ratings: 'very popular with other children', 'unusually happy and contented', 'makes friends extremely easily' and 'extremely energetic, never tired'. In addition, at age 16 years survey members self-completed the Maudsley Personality Inventory, from which a summary measure of extraversion was derived, as this was previously found to be associated with midlife positive wellbeing in this cohort. RESULTS: Being a happy child, defined as receiving at least two of the above teacher ratings, was positively associated with midlife functioning and wellbeing, specifically a low probability of lifetime emotional problems, a high frequency of contact with friends or relatives, engagement in social activities, and to a lesser extent feeling satisfied with accomplishments in working life. These associations were independent of father's social class, childhood cognition, educational attainment, and midlife occupational social class. There were no independent associations between being a happy child and educational or occupational attainment, being married, engagement in prosocial activities, taking leadership in community activities, and with life satisfaction in general or with family life. Extraversion was associated with a low probability of lifetime emotional problems, high engagement in social activities, being married, general midlife life satisfaction, and satisfaction with family life, but not with social contact, prosocial activity, leadership activity, or work satisfaction. While childhood conduct and emotional problems were associated with few of the social and life satisfaction outcomes, the former were negatively associated with educational and occupational attainment, and positively with divorce, whereas the latter were negatively associated with being married. CONCLUSIONS: Prospectively rated childhood wellbeing has long-term beneficial links to adult functioning; our results also support the view that positive wellbeing has a unique impact on these outcomes, and does not merely represent the absence of mental ill-health.     

Visuospatial over verbal demands in predicting Tower of London planning tasks

The role of verbal and visuospatial information processing in Tower of London (TOL) tasks was investigated. The first part of the investigation examined the verbal and visuospatial abilities and preferred cognitive style (visualizer vs. verbalizer) of 79 participants, in an inter-individual differences approach. Visuospatial abilities significantly predicted TOL performance, but the impact of cognitive style was negligible. The second part applied a dual-task manipulation of concurrent interference of TOL planning tasks on verbal and visuospatial memory, using the same participants. Concurrent processing of the TOL tasks diminished visuospatial memory performance considerably but had no effect on verbal memory, and there was no interaction between cognitive style and memory. These findings clearly underscore the role of visuospatial information processing in TOL tasks and indicate little bearing of verbal or visual cognitive style on TOL problem solving. These results have important implications for TOL and cognitive style in clinical application and cognitive neuroimaging research.     

Are Self‐Report Measures of Adaptive Functioning Appropriate for those High in Psychopathic Traits?

There is ongoing debate about the methods that evaluators should use to assess the adaptive functioning of an individual in an Atkins claim, including the appropriateness of using self‐report measures and extent to which adaptive functioning measures are valid for persons with a history of violent offending. This study examined whether offenders' self‐report adaptive functioning scores tended to decrease as their level of psychopathic traits increased. Eighty‐five male felony probationers completed the self‐report version of the Adaptive Behavior Assessment System – II (ABAS‐II: Harrison & Oakland, 2003), the Psychopathic Personality Inventory – Revised (PPI‐R: Lilienfeld & Widows, 2005), and a brief intelligence screening measure. ABAS‐II composite scores were negatively correlated with PPI‐R Self‐Centered Impulsivity and Coldheartedness scores, but positively correlated with Fearless Dominance scores. These relationships appeared to be due, in part, to over‐reporting symptoms of impairment across measures, suggesting that scores on self‐report adaptive functioning measures may be especially susceptible to feigning. Copyright © 2012 John Wiley & Sons, Ltd.     

Effects of dehydroepiandrosterone supplementation during stressful military training: a randomized, controlled, double-blind field study

Dehydroepiandrosterone (DHEA) and DHEA sulfate (DHEAS) are anabolic prehormones involved in the synthesis of testosterone. Both have been shown to exert neuroprotective effects during stress. In this randomized, controlled, double-blind field study, we examined the effects of a 12-day DHEA regimen on stress indices in military men undergoing survival training. Forty-eight men were randomized to either a DHEA treatment group or placebo control group. The treatment group received 50 mg of oral DHEA supplementation daily for 5 days during classroom training followed by 7 days of 75 mg during stressful field operations. Control subjects received identical placebo pills. Salivary assays (DHEA[S], testosterone, and cortisol) were conducted at four time points: distal pre-stress (T1), proximal pre-stress (T2), mock-captivity stress (T3), and 24 h recovery (T4). Subjective distress was also assessed at T1, T3, and T4. As expected, DHEA treatment resulted in higher salivary concentrations of DHEA and DHEAS during daily living, mock-captivity stress, and recovery. Similar patterns were observed for salivary markers of anabolic balance: DHEA/cortisol, DHEAS/cortisol, and testosterone/cortisol concentration ratios. Despite notable time effects, no group differences emerged for subjective distress. A brief, low dose DHEA regimen yielded large increases in salivary DHEA(S) concentrations and enhanced anabolic balance throughout sustained military stress. These physiological changes did not extrapolate to subjective distress.     

Second-order mappings in grapheme–color synesthesia

Typically, the search for order in grapheme–color synesthesia has been conducted by looking at the frequency of certain letter–color associations. Here, we report stronger associations when second-order similarity mappings are examined—specifically, mappings between the synesthetic colors of letters and letter shape, frequency, and position in the alphabet. The analyses demonstrate that these relations are independent of one other. More strikingly, our analyses show that each of the letter–color mappings is restricted to one dimension of color, with letter shape and ordinality linked to hue, and letter frequency linked to luminance. These results imply that synesthetic associations are acquired as the alphabet is learned, with associations involving letter shape, ordinality, and frequency being made independently and idiosyncratically. Because these mappings of similarity structure between domains (letters and colors) are similar to those found in numerous other cognitive and perceptual domains, they imply that synesthetic associations operate on principles common to many aspects of human cognition.     

Microstructural organization of corpus callosum projections to prefrontal cortex predicts bimanual motor learning

The corpus callosum (CC) is the largest white matter tract in the brain. It enables interhemispheric communication, particularly with respect to bimanual coordination. Here, we use diffusion tensor imaging (DTI) in healthy humans to determine the extent to which structural organization of subregions within the CC would predict how well subjects learn a novel bimanual task. A single DTI scan was taken prior to training. Participants then practiced a bimanual visuomotor task over the course of 2 wk, consisting of multiple coordination patterns. Findings revealed that the predictive power of fractional anisotropy (FA) was a function of CC subregion and practice. That is, FA of the anterior CC, which projects to the prefrontal cortex, predicted bimanual learning rather than the middle CC regions, which connect primary motor cortex. This correlation was specific in that FA correlated significantly with performance of the most difficult frequency ratios tested and not the innately preferred, isochronous frequency ratio. Moreover, the effect was only evident after training and not at initiation of practice. This is the first DTI study in healthy adults which demonstrates that white matter organization of the interhemispheric connections between the prefrontal structures is strongly correlated with motor learning capability.