Left-handedness in twin families: support of an environmental hypothesis

Information on handedness, assessed as writing-hand, was collected from 197 MZ twin pairs and 203 DZ twin pairs and from their parents, spouses, and children. Associations for pairs of relatives were studied by 2 X 2 tables, computing chi squared-values and tetrachoric correlations. Correlations of about .3 were obtained for mother-offspring and sibling pairs, while for cousins the correlation was .25 (in a small sample). No other significant associations were found, not even for twins. These results suggest only a small, if any, genetic effect, and only a small environmental between family effect, most of which seems to be a maternal effect. The lack of cotwin correlations and correlations for one of the twins with her/his ordinary brothers/sisters suggest the existence of an effect specific to twins, since the correlation for pairs of ordinary siblings is significant. Conclusions drawn from twin studies alone may be biased. The frequency of left-hand writers has increased from 1% to 10% in the different age groups born during the last century in Norway. This age effect is present mainly in hand writing and not so much in handedness generally, suggesting a decrease in cultural repression against left-hand writing.     

Executive Functioning Correlates of <Emphasis Type="Italic">DSM-5</Emphasis> Maladaptive Personality Traits: Initial Evidence from an Italian Sample of Consecutively Admitted Adult Outpatients

In order to evaluate the associations between computer-administered tasks of executive functioning (EF), and maladaptive personality domains and traits listed in DSM-5 Alternative Model of Personality Disorders, 53 consecutively admitted psychotherapy outpatients (female participants: n?=?27, 50.9%; male participants: n?=?26, 49.1%; participants’ mean age?=?37.28 years, SD?=?11.50 years) were administered the Psychology Experiment Building Language (PEBL) EF tasks and the Personality Inventory for DSM-5 (PID-5). According to rank-order correlation analyses, a number of non-negligible and specific associations were observed between selected PID-5 scales and indices of participants’ performance on EF tasks. MM robust regression models showed that participants’ performance on computer-administered EF tasks explained a non-negligible amount of variance in selected PID-5 scale scores (median R² value?=?.17). As a whole, our trait-level analyses of PID-5 dimensions suggest the clinical usefulness of integrating self-reports and EF laboratory tasks in routine clinical assessment.     

Genetic and environmental contributions to the co-occurrence of depressive personality disorder and DSM-IV personality disorders

One of the main controversies with regard to depressive personality disorder (DPD) concerns the co-occurrence with the established DSM-IV personality disorders (PDs). The main aim of this study was to examine to what extent DPD and the DSM-IV PDs share genetic and environmental risk factors, using multivariate twin modeling. The DSM-IV Structured Interview for Personality was applied to 2,794 young adult twins. Paranoid PD from Cluster A, borderline PD from Cluster B, and all three PDs from Cluster C were independently and significantly associated with DPD in multiple regression analysis. The genetic correlations between DPD and the other PDs were strong (.53-.83), while the environmental correlations were moderate (.36-.40). Close to 50% of the total variance in DPD was disorder specific. However, only 5% was due to disorder-specific genetic factors, indicating that a substantial part of the genetic vulnerability to DPD also increases the vulnerability to other PDs.     

Learning new vocabulary in German: the effects of inferring word meanings,type of feedback,and time of test

In the present study, introductory-level German students read a simplified story and learned the meanings of new German words by reading English translations in marginal glosses versus trying to infer (i.e., guess) their translations. Students who inferred translations were given feedback in English or in German, or no feedback at all. Although immediate retention of new vocabulary was better for students who used marginal glosses, students who inferred word meanings and then received English feedback forgot fewer translations over time. Plausible but inaccurate inferences (i.e., those that made sense in the context) were more likely to be corrected by students who received English feedback as compared with German feedback, providing support for the beneficial effects of mediating information. Implausible inaccurate inferences, however, were more likely to be corrected on the delayed vocabulary test by students who received German feedback as compared with English feedback, possibly because of the additional contextual support provided by German feedback.     

An interpersonal analysis of pathological personality traits in DSM-5

The proposed changes to the personality disorder section of the Diagnostic and statistical manual of mental disorders (5th ed.) places an increased focus on interpersonal impairment as one of the defining features of personality psychopathology. In addition, a proposed trait model has been offered to provide a means of capturing phenotypic variation on the expression of personality disorder. In this study, the authors subject the proposed DSM-5 traits to interpersonal analysis using the inventory of interpersonal problems-circumplex scales via the structural summary method for circumplex data. DSM-5 traits were consistently associated with generalized interpersonal dysfunction suggesting that they are maladaptive in nature, the majority of traits demonstrated discriminant validity with prototypical and differentiated interpersonal problem profiles, and conformed well to a priori hypothesized associations. These results are discussed in the context of the DSM-5 proposal and contemporary interpersonal theory, with a particular focus on potential areas for expansion of the DSM-5 trait model.     

An invariant dimensional liability model of gender differences in mental disorder prevalence: evidence from a national sample

Epidemiological studies of categorical mental disorders consistently report that gender differences exist in many disorder prevalence rates and that disorders are often comorbid. Can a dimensional multivariate liability model be developed to clarify how gender impacts diverse, comorbid mental disorders? We pursued this possibility in the National Epidemiologic Survey on Alcohol and Related Conditions (NESARC; N = 43,093). Gender differences in prevalence were systematic such that women showed higher rates of mood and anxiety disorders, and men showed higher rates of antisocial personality and substance use disorders. We next investigated patterns of disorder comorbidity and found that a dimensional internalizing-externalizing liability model fit the data well, where internalizing is characterized by mood and anxiety disorders, and externalizing is characterized by antisocial personality and substance use disorders. This model was gender invariant, indicating that observed gender differences in prevalence rates originate from women and men's different average standings on latent internalizing and externalizing liability dimensions. As hypothesized, women showed a higher mean level of internalizing, while men showed a higher mean level of externalizing. We discuss implications of these findings for understanding gender differences in psychopathology and for classification and intervention.     

Sexting as a predictor of sexual behavior in a sample of Czech adolescents

The purpose of this longitudinal study is to examine the relationship between teen sexting and offline sexual behavior. Using a sample of 1134 Czech adolescents aged 10–18 (M_age = 13.84, SD = 1.94, girls = 58.8%) from 55 schools, the latent growth model of offline sexual behavior with sexting as a time-varying covariate was employed. Participants differed at baseline for offline sexual behavior at both individual and school levels, and they varied in the growth rate of offline sexual behavior at the individual level. Only age and sensation seeking explained the variability at baseline of offline sexual behavior. The positive association between sexting and offline sexual behavior was not constant across time. However, sexting at baseline predicted offline sexual behavior a half year and one year later. Sexting may be treated as a precursor of offline sexual behavior.     

Breath Versus Emotions: The Impact of Different Foci of Attention During Mindfulness Meditation on the Experience of Negative and Positive Emotions

Mindfulness meditation yields beneficial effects on the processing of emotions. However, it is still unclear whether the focus of attention during meditation influences these effects. In the present study we aimed at comparing the effects of breathing meditation and emotion-focused meditation on the immediate and delayed processing of negative and positive emotions. The study included 65 adult novice meditators who were exposed to positively and negatively valenced film clips. Participants were randomly assigned to three conditions. While watching the films at t1, they were asked to mindfully focus on their breath (condition 1), on emotions (condition 2), or on nothing in particular (condition 3). Ten minutes later at t2, comparable film clips were shown but all participants watched them without taking up a mindful attitude. Dependent measures were emotional states at t1 and t2. Participants of both meditation conditions particularly showed a more preferable delayed emotional reaction to negative stimuli than participants of the control condition. Breathing meditation and emotion-focused meditation may constitute effective emotion regulation strategies to deal with negatively valenced emotional states.