Perspectives in psychology

The Psychological Record - It is too early to say with any certainty that experiential and phenomenological views are on the way out. In spite of the problems surrounding this type of postulation,...     

Genetic effects explain the stability of psychopathic personality from mid- to late adolescence

This study examined the importance of genetic and environmental influence for the stability of psychopathic personality between mid- and late adolescence. The target sample consisted of all 1,480 male and female twin pairs born in Sweden between 1985 and 1986. Psychopathic personality was measured with the Youth Psychopathic Traits Inventory (YPI; H. Andershed, M. Kerr, M. Stattin, & S. Levander, 2002) when the participants were 16 and 19 years old. Results showed that the 3 psychopathic personality dimensions were stable at different levels of analysis and linked to a stable higher order general factor (i.e., psychopathic personality factor). Genetic factors contributed substantially to the stability of this general higher order factor, whereas environmental factors were of little importance. However, the authors also found specific genetic stability in the Callous/unemotional and Impulsive/irresponsible dimension. Thus, the model provides evidence for etiologic generality and etiologic specificity for the stability of psychopathic personality between mid- and late adolescence.     

Genetic probes of three theories of maternal adjustment: I. Recent evidence and a model.

Studies focusing on genetic and social influences on maternal adjustment will illumine mother's marriage, parenting, and the development of psychopathology in her children. Recent behavioral genetic research suggests mechanisms by which genetic and social influences determine psychological development and adjustment. First, heritable, personal attributes may influence individuals' relationships with their family members. These genetically influenced family patterns may amplify the effects of adverse, heritable personal attributes on adjustment. Second, influences unique to siblings may be the most important environmental determinants of adjustment. We derive three hypotheses on maternal adjustment from integrating these findings from genetic studies with other contemporary research on maternal adjustment. First, mother's marriage mediates the influence of her heritable, personal attributes on her adjustment. Second, mother's recall of how she was parented is partially genetically influenced, and both her relationships with her spouse and her child mediate the impact of these genetically influenced representations on her current adjustment. Third, characteristics of mother's spouse are important influences on difference between her adjustment and that of her sister's. These sibling-specific influences are unrelated to mother's heritable attributes. The current article develops this model, and [figure: see text] the companion article describes the Twin Mom Study that was designed to test it as well, as its first findings. Data from this study can illumine the role of family process in the expression of genetic influence and lead to specific family interventions designed to offset adverse genetic influences.     

Genetic probes of three theories of maternal adjustment: II. Genetic and environmental influences.

This is the first report of the Twin Mom Study, an investigation of three hypotheses concerning influences on maternal adjustment. These hypotheses concern the role of the marital and parent-child relationships in mediating genetic influences on maternal adjustment and on the importance of the mothers' marital partners as a specifiable source of influences on their adjustment not shared with their sisters. The study's sample of 150 monozygotic (MZ) twins and 176 dizygotic (DZ) twins was drawn randomly from the Swedish Twin Registry and is, with some small exceptions, likely to be representative of women in the Swedish population. The sample included the marital partners of these twins and their adolescent children. Self-report and coded videotapes were a source of information about family process. Results reported in this first report focus on comparability of American and Swedish samples on scales measuring psychiatric symptoms, and on an analysis of genetic and environmental influences on nine measures of mothers' adjustment. Results suggest comparability between the US and Sweden. Genetic influences were found for all measures of adjustment, particularly in the psychological manifestations of anxiety and for smoking. The pattern of findings also underscored the importance of influences unique to each sibling within the twin pair, thus focusing attention on the potential role of marital partners in maternal adjustment. Results also suggested that experiences shared by the twin sisters, experiences unrelated to their genetic similarity, may influence their fearfulness and alcohol consumption. Our model did not include these influences and thus must be amended.     

The genetic basis of entrepreneurship: Effects of gender and personality

Extending previous research on the genetic underpinnings of entrepreneurship, we investigate gender differences in the genetic influences on the tendency of people to become entrepreneurs. We also examined two mediating variables through which genetic factors may impact this tendency: extraversion and neuroticism. Based on 1285 pairs of identical twins (449 male and 836 female pairs) and 849 pairs of same-sex fraternal twins (283 male and 566 female pairs), we found that females have a strong genetic influence and zero shared-environmental influences on their tendency to become entrepreneurs. In contrast, males show zero genetic influence, but a large shared-environmental influence. Extraversion and neuroticism mediate the genetic influences on women’s tendency to become entrepreneurs, whereas extraversion mediates shared-environmental influences on men’s tendency to become entrepreneurs. We discuss this sharp difference in genetic influences on entrepreneurship across gender groups and highlight the different challenges that men and women face in their entrepreneurial endeavors.     

The Swedish version of the parent-rated Junior Temperament and Character Inventory (J-TCI)

To evaluate the psychometric characteristics of the Swedish version of the Junior Temperament and Character Inventory (J-TCI), it was sent to parents of 9- and 12-yr.-old twins in Sweden. The final number of responders was 196 parents who rated 92 female and 104 male twin pairs. The inventory of one twin, randomly chosen from each pair, was included in the analyses. Reward Dependence, Persistence, and Cooperativeness were scored higher in girls; Novelty Seeking was higher in the 9-yr.-olds and Persistence in the 12-yr.-olds. Pearson's correlations showed that some dimensions were not statistically independent from each other, even if the covariance was moderate. Internal consistency (Cronbach's alpha) was satisfactory for Harm Avoidance, Novelty Seeking, Self-Directedness, and Cooperativeness (.68-.81), while it was lower in those dimensions that had fewer items. The Swedish parent version of the J-TCI shared about the same psychometric characteristics as found in international samples.     

Radon and cigarette smoking: perceptions of this synergistic health risk.

Past approaches to the measurement of the perceived risk of combined hazards have failed to demonstrate awareness of synergy (S. E. Hampson et al., 1998; D. Hermand, E. Mullet, & B. Coutelle, 1995; D. Hermand, E. Mullet, & S. Lavieville, 1997). Respondents (N = 650) were provided with information about the synergistic risk of lung cancer from the combination of smoking and radon, and their risk perceptions were assessed on two occasions. At Time 1, using Likert-type scales, there was no evidence of synergistic risk perception. At Time 2, using a scale based on the appraisal of relative risk with anchors allowing for the expression of synergy, the combined hazard of radon and smoking was rated as significantly more of a health risk than the single hazards. The findings are discussed in terms of methodological issues in assessing synergistic risk.