Background: This study tested model-driven predictions regarding working memory's role in the organizational problems associated with ADHD. Method: Children aged 8-13 (M = 10.33, SD = 1.42) with and without ADHD (N = 103; 39 girls; 73% Caucasian/Non-Hispanic) were assessed on multiple, counterbalanced working memory tasks. Parents and teachers completed norm-referenced measures of organizational problems (Children's Organizational Skills Scale; COSS). Results: Results confirmed large magnitude working memory deficits (d = 1.24) and organizational problems in ADHD (d = 0.85). Bias-corrected, bootstrapped conditional effects models linked impaired working memory with greater parent-and teacher-reported inattention, hyperactivity/impulsivity, and organizational problems. Working memory predicted organization problems across all parent and teacher COSS subscales (R 2 = .19-.23). Approximately 38%-57% of working memory's effect on organization problems was conveyed by working memory's association with inattentive behavior. Unique effects of working memory remained significant for both parent-and teacher-reported task planning, as well as for teacher-reported memory/materials management and overall organization problems. Attention problems uniquely predicted worse organizational skills. Hyperactivity was unrelated to parent-reported organizational skills, but predicted better teacher-reported task planning. Conclusions: Children with ADHD exhibit multisetting, broad-based organizational impairment. These impaired organizational skills are attributable in part to performance deficits secondary to working memory dysfunction, both directly and indirectly via working memory's role in regulating attention. Impaired working memory in ADHD renders it extraordinarily difficult for these children to consistently anticipate, plan, enact, and maintain goal-directed actions.

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Binge drinking is associated with clinically significant individual-level and public health consequences. The topography of binge drinking may influence the emergence of consequences but studies of topography require a higher level of temporal resolution than is typically available in epidemiological research. To address topography across the five “peak” years of binge drinking (18 to 23 years), we assessed daily binge drinking via successive 90-day Timeline Follow back interviews of 645 young adults (resulting in almost 700,000 data points). Results showed a weekend “pulse” of binge drinking that remained consistent across the entire five year span, with occasional holiday-based perturbations. Two-part latent growth curve (LGC) modeling applied to this dataset showed that the often-observed decrease in drinking associated with “maturing out” was due more to decreased participation in binge drinking occasions, rather than to amounts consumed when drinking (intensity). Similarly, the number of binge drinkers varied by day of the week, but the intensity of binge drinking, for those drinking, varied little by day of the week. This approach also showed distinctive predictors for participation and intensity; baseline expectancies and sociability accounted for individual differences in participation, whereas impulsivity-sensation seeking predicted intensity. Individual patterns of binge drinking participation and intensity also predicted drinking consequences over the 5 years of the study. Given these results, binge drinking patterns may serve as a useful phenotype for future research on pathological drinking.

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Prosociality is one construct included in the developmental propensity model proposed by Lahey and colleagues to explain the development of conduct problems in childhood and adolescence. Findings from previous literature on two facets of prosociality, dispositional sympathy and respect for rules, suggest that both may have genetic and nonshared environmental influences but only the latter may have shared environmental influence. The goal of the current paper was to explore the structure of the prosociality disposition from a measurement perspective as well as to examine the etiology of this construct. The sample consisted of 686 twin pairs ages 7 to 13. Parents rated their children’s prosociality using the Child and Adolescent Dispositions Scale. The factor structure of the prosociality scale was examined using confirmatory factor analysis to compare a one-factor model with a two-factor model. Twin analyses were used to examine the proportion of variance associated with genetic and environmental effects on the latent factor(s) from the best-fitting model. Results of the current study suggest that prosociality is a disposition that can be conceptualized as two related factors rather than a unitary dimension. These two factors map onto the subscales of the prosociality dimension (dispositional sympathy and respect for rules). Both factors had significant genetic and nonshared environmental influences, but only respect for rules had significant shared environmental influences. Examining the dispositional sympathy and respect for rules facets of prosociality separately allowed for the discovery that shared environmental factors may have more impact on respect for rules than sympathy.