Genetic and environmental links between motor activity level and attention problems in early childhood

Cross‐lagged biometric models were used to examine genetic and environmental links between actigraph‐assessed motor activity level (AL) and parent‐rated attention problems (AP) in 314 same‐sex twin pairs (MZ = 145, DZ = 169) at ages 2 and 3 years. At both ages, genetic correlations between AL and AP were moderate (r_a2 = .35; r_a3 = .39) indicating both overlap and specificity in genetic effects across the two domains. Within‐ and across‐age phenotypic associations between AL and AP were entirely due to overlapping genetic influences. There was a unidirectional effect of AL at age 2 predicting later AP. For AP, genetic and environmental influences from age 2 were transmitted to age 3 via stability effects and from AL. For AL, across‐age effects were transmitted only via stability. These results suggest that overactivity in late infancy may impact the later development of problems related to inattention, and that genetic factors explain the association between the two domains.     

Stress Reactivity as a Pathway from Attentional Control Deficits in Everyday Life to Depressive Symptoms in Adolescent Girls

The goal of this research was to expand theoretical models of adolescent depression to determine whether individual differences in cognitive processing—specifically attentional control deficits—help to explain increased risk for depression during adolescence. We also examined whether this pathway was stronger in girls than in boys. A longitudinal design was used to examine whether poor attentional control in everyday life (i.e., difficulties shifting between ideas, tasks, and activities) contributes to depression over time by fostering higher levels of stress reactivity. Youth (298 boys, 338 girls) completed questionnaires assessing stress reactivity (6th and 7th grades) and depressive symptoms (6th, 7th and, 8th grades); teachers completed the shifting subscale of the Behavior Rating Scale of Executive Function (Gioia et al. 2000a) to assess attentional control (6th and 7th grades). Structural equation modeling analyses provided support for the predicted pathway in girls but not boys, yielding a significant indirect effect from 6th grade shifting deficits to 8th grade depressive symptoms via 7th grade stress reactivity. These results suggest that attentional control deficits in early adolescence heighten girls’ sensitivity to stress and consequent depressive symptoms, providing a critical direction for efforts to decrease adolescent girls’ risk for depression.     

Activist purpose orientation: Definition and predictors

Activism is responsible for many of the positive social changes we have seen across time, and is central to pushing for continued social change. However, these positive outcomes do not come without a cost, as activism can also be draining and can lead to physical and emotional harm for those involved. Social policies and intervention programs have addressed how to help people maintain their engagement with activism aims, though few have considered the motivational role of purpose in life. As purpose in life involves a sustained commitment to one's goals, having a purpose in life centered around activism may help an individual remain committed to activism and to the creation of change in the face of these obstacles. If activist purpose can help us understand and predict who is likely to remain engaged in activism, then it is valuable to consider what factors influence the development of activist purpose, in order to continue necessary social change. Thus, in this work we define activist purpose, and theorize as to what factors may be relevant to the development of an activist purpose by situating predictors of activism and collective action within the literature on pathways to purpose in life. This work may thus provide a greater understanding of how to encourage activism or reduce the harmful effects associated with activism.     

Do individual differences in sociosexuality represent genetic or environmentally contingent strategies? Evidence from the Australian twin registry

Although men are substantially more interested than women in casual sex, there is ample variation in this trait (sociosexuality) within both sexes. One theory hypothesizes that within-sex sociosexual variation results from genetic variation maintained by frequency-dependent selection. If so, sociosexuality should be substantially heritable. A competing theory is that children acquire their mating strategy after observing their parents' relationship. By this theory, sociosexuality should reveal a strong shared environmental component. The authors studied genetic and environmental influences on sociosexuality using a large, representative volunteer twin sample. Parental marital instability was modestly associated with sociosexuality, but this could have been due to either genetic or environmental factors. Consistent with genetic theory, familial resemblance appeared primarily due to additive genetic rather than shared environmental factors.     

Composition and the cases

Some strange cases have gripped philosophers of mind. They have been deployed against materialism about human persons, functionalism about mentality, the possibility of artificial intelligence, and more. In this paper, I cry “foul”. It’s not hard to think that there’s something wrong with the cases. But what? My proposal: their proponents ignore questions about composition (questions about when some things make up another). And ignoring composition is a mistake. Indeed, materialists about human persons, functionalists about mentality, and believers in the possibility of artificial intelligence can plausibly deploy moderate theories of composition in defense of their views. And as it turns out, these strange cases are an interesting source of evidence for moderate theories of composition.