Continuity and change in psychopathic traits as measured via normal-range personality: a longitudinal-biometric study

The discriminant validity of the interpersonal-affective and social deviance traits of psychopathy has been well documented. However, few studies have explored whether these traits follow distinct or comparable developmental paths. The present study used the Multidimensional Personality Questionnaire (A. Tellegen, in press) to examine the development of the psychopathic traits of Fearless Dominance (i.e., interpersonal-affective) and Impulsive Antisociality (i.e., social deviance) from late adolescence to early adulthood in a longitudinal-epidemiological sample of male and female twins. Results from mean- and individual-level analyses revealed stability in Fearless Dominance from late adolescence to early adulthood, whereas Impulsive Antisociality declined over this developmental period. In addition, biometric findings indicated greater genetic contributions to stability in these traits and greater nonshared environmental contributions to their change over time. Collectively, these findings suggest distinct developmental trends for psychopathic traits from late adolescence to early adulthood.     

Time-dependent modulation of inhibitory avoidance memory by spermidine in rats

The polyamines, spermine, spermidine, and putrescine, are a group of aliphatic amines that may act as physiological modulators of N-methyl-D-aspartate (NMDA) receptors. Although the modulatory role of polyamines in NMDA receptor function has long been known, the effects of polyamines on learning and memory only recently began to be unraveled. In the present study, we investigated the effect of bilateral infusions of spermidine (0.02-2 nmol), a polyamine agonist, into the CA1 region of the rat dorsal hippocampus on inhibitory avoidance learning 30 min pre-training, immediately post-training, 6 h post-training, or 10 min pre-test. Bilateral microinjections of 0.2 nmol spermidine prolonged step-down latencies compared to the respective control group when administered 30 min pre-training or immediately post-training. These results provide evidence that the modulatory effects of spermidine on the acquisition and/or early consolidation of memory of inhibitory avoidance tasks in the hippocampus occur within a limited time window.     

Symptom-based subfactors of DSM-defined conduct disorder: evidence for etiologic distinctions

Past research investigating the structure of conduct disorder (CD) symptoms has provided evidence of a phenotypic distinction between aggressive and rule-breaking subfactors of CD. However, evidence of etiologic distinctions between these subfactors has not been reported to date. In the current study, the authors investigated this issue in a sample of 1,151 male twins who were 17 years of age. The results indicate that aggressive and rule-breaking CD subfactors have both common and distinct etiologic influences, with shared environmental influences playing a significant role in rule-breaking behaviors. The authors discuss implications of these findings for the assessment and treatment of CD.     

Etiologic connections among substance dependence,antisocial behavior,and personality: modeling the externalizing spectrum

A hierarchical biometric model is presented of the origins of comorbidity among substance dependence, antisocial behavior, and a disinhibited personality style. The model posits a spectrum of personality and psychopathology, united by an externalizing factor linked to each phenotype within the spectrum, as well as specific factors that account for distinctions among phenotypes within the spectrum. This model fit self-report and mother-report data from 1,048 male and female 17-year-old twins. The variance of the externalizing factor was mostly genetic, but both genetic and environmental factors accounted for distinctions among phenotypes within the spectrum. These results reconcile evidence for general and specific causal factors within the externalizing spectrum and offer the externalizing factor as a novel target for future research.     

A Formal Ontological Theory Based on Timeless Events

I offer a formal ontological theory where the basic building blocks of the world are timeless events. The composition of events results in processes. Spacetime emerges as the system of all events. Things are construed as bundles of processes. I maintain that such a view is in accord with General Relativity and offers interesting prospects for the foundations of classical and quantum gravity.     

Personality Trait Change Across Late Childhood to Young Adulthood: Evidence for Nonlinearity and Sex Differences in Change

We explored patterns of self‐reported personality trait change across late childhood through young adulthood in a sample assessed up to four times on the lower order facets of Positive Emotionality, Negative Emotionality (NEM), and Constraint (CON). Multilevel modelling analyses were used to describe both group‐ and individual‐level change trajectories across this time span. There was evidence for nonlinear age‐related change in most traits, and substantial individual differences in change for all traits. Gender differences were detected in the change trajectories for several facets of NEM and CON. Findings add to the literature on personality development by demonstrating robust nonlinear change in several traits across late childhood to young adulthood, as well as deviations from normative patterns of maturation at the earliest ages. Copyright © 2015 European Association of Personality Psychology     

Gender and Age Differences in Brazilian Children's Friendship Nominations and Peer Sociometric Ratings

This article reports on an investigation into the relation between young adults' retrospective reports of their mothers' and fathers' division of household labor (egalitarian or traditional) and parenting styles (authoritative, permissive, authoritarian, or disengaged). Participants' own gender attitudes were also tested in relation to parents' division of labor and parenting. The sample included 294 women and men (M =19-years old) who were raised in 2-parent households and came from a range of ethnic backgrounds. When mothers' parenting was evaluated, permissive parenting was more likely among those from egalitarian households whereas authoritarian parenting was more likely among those from traditional households. When fathers' parenting was evaluated, authoritative parenting was more likely among participants from egalitarian households and disengaged parenting was more likely among those from traditional households. The association between fathers' parenting style and division of labor was specific to the division of childcare (rather than housework). Participants' gender attitudes were not related to parents' division of labor or parenting style.     

Feelings or cognitions? Moral cognitions and emotions as longitudinal predictors of prosocial and aggressive behaviors

There is debate regarding the roles of sociomoral cognitions and emotions in understanding moral development. The short-term longitudinal relations among perspective taking, sympathy, prosocial moral reasoning, prosocial behaviors and aggression in adolescents were examined. Participants were 489 students (M age = 12.28 years, SD = .48; 232 boys) in public and private schools from predominantly middle class families in Valencia, Spain. Students completed measures of perspective taking, sympathy, prosocial moral reasoning, prosocial behaviors, and aggressive behaviors. Overall, structural equation modeling analyses showed that moral reasoning and emotions were interrelated and predicted both prosocial behaviors and aggression. Discussion focuses on the relevance of both social cognitions and emotions in moral development.     

Lactate threshold prediction by blood glucose and rating of perceived exertion in people with type 2 diabetes

The validity of rating of perceived exertion (RPE) in predicting lactate threshold during an incremental test was analyzed in 15 men with type 2 diabetes (M age = 53.4 yr., SD = 12.9). Blood glucose, lactate, and minute ventilation (VE)/VO2 responses identified the lactate, ventilatory, and glucose thresholds. Workloads (W) corresponding to RPEs 12, 13, 14, and 15 were determined. Second-order polynomials fit to VE/W and [lac]/W ratios corresponding to RPEs of 9-10, 12-13, and 16-17 also identified workloads above which there was an overproportional increase in VE and [lac]. These workload breakpoints did not differ, although at RPE 12 underestimated and at RPE 15 overestimated lactate threshold. RPE 13 and 14 and the responses of VE/W and [lac]/W to submaximal exercise accurately predicted lactate threshold.     

Images of Thin and Plus-Size Models Produce Opposite Effects on Women’s Body Image,Body Dissatisfaction,and Anxiety

Mainstream media’s promotion of dangerously thin female images likely lowers self-image satisfaction and contributes to pathological body concerns and disordered eating among women. We tested upward and downward social-comparison effects on self-evaluations by exposing 145 Spanish women to images of thin (upward) or overweight (downward) models. We also tested whether explicitly asking or not asking participants to compare themselves with the models would moderate social comparison effects. Exposure to thin models deteriorated body image while increasing body dissatisfaction and anxiety. Conversely, exposure to overweight models improved body image and decreased body dissatisfaction but it did not affect anxiety. Whether participants were asked to compare themselves to the models explicitly or implicitly had no effect on the participants’ responses. Furthermore, pre-existing body image concerns were not associated with the pre-to-post exposure effects. We propose that increasing the representation of normal weight and overweight women in media advertisements could help to neutralize or at least reduce the negative impact of media’s practice to idealize thin and overly thin women as symbols of female beauty.