Considerable evidence has demonstrated a critical role for the nucleus accumbens (NAc) in the acquisition and flexibility of behavioral strategies. These processes are guided by the activity of two discrete neuron types, dopamine D1- or D2-receptor expressing medium spiny neurons (D1-/D2-MSNs). Here we used the IntelliCage, an automated…

The present study examined age differences in performance on the Tower of London, a measure of strategic planning, in a diverse sample of 890 individuals between the ages of 10 and 30. Although mature performance was attained by age 17 on relatively easy problems, performance on the hardest problems showed improvements into the early 20s.…

We examined whether self-restraint in early childhood predicted individual differences in 3 executive functions (EFs; inhibiting prepotent responses, updating working memory, and shifting task sets) in late adolescence in a sample of approximately 950 twins. At ages 14, 20, 24, and 36 months, the children were shown an attractive toy and told not…

In this study, the authors examined whether exposure to relational victimization was associated with children's thoughts, emotions, and behavior in an unfamiliar, challenging peer context. Children (110 girls, 96 boys; mean age = 10.13 years, SD = 1.16) reported on their exposure to relational victimization by peers. Following a challenging…

Adolescence is a developmental period that entails substantial changes in affective and incentive-seeking behavior relative to both childhood and adulthood, including a heightened propensity to engage in risky behaviors and experience persistent negative and labile mood states. This review discusses the emotional and incentive-driven behavioral…

It has been hypothesized that sensation seeking and impulsivity, which are often conflated, in fact develop along different timetables and have different neural underpinnings, and that the difference in their timetables helps account for heightened risk taking during adolescence. In order to test these propositions, the authors examined age…

The relations of children's (n=214 at Time 1; M age=6 years at Time 1) dispositional sympathy to adult-reported and behavioral measures of effortful control (EC) and impulsivity were examined in a longitudinal study including five assessments, each two years apart. Especially for boys, relatively high levels of EC and growth in EC were related to…

Compared the performance of learning disabled and normal-achieving third- and fourth-grade children on Kagan's Matching Familiar Figures Test to determine group differences along the impulsivity-reflection dimension. Overall results suggest that learning disabled children are not more impulsive but rather use poor strategic behavior in processing…

Investigated time conceptualizations and delay of gratification capacities of 64 6- to 10-year-olds identified as impulsive or reflective according to performance on Kagan's Matching Familiar Figures Test. They were administered a maintenance of delay of gratification task, a time concept questionnaire, and several measures of temporal perspective…

This paper presents four studies which illustrate the variety of deficits in executive function displayed by individuals with autism. The concept of executive function is used to encompass all the mental operations which are involved in self-reflective and goal-directed behavior. Four forms of executive control are addressed: mental disengagement,…

The purpose of this research was to determine if training in analytic processing would increase the probability that subjects behaving impulsively prior to training would behave more reflectively following training. The study attempted to alter impulsive behavior in terms of number of errors by training identified impulsive boys to use component…