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Growing up in poverty is associated with reduced cognitive achievement as measured by standardized intelligence tests, but little is known about the underlying neurocognitive systems responsible for this effect. We administered a battery of tasks designed to tax-specific neurocognitive systems to healthy low and middle SES children screened for medical(More)
Initiation of drug use and other risky behavior in preadolescence is associated with poor developmental outcomes. In this research, we examine models that ascribe the trajectory to (a) weak executive cognitive function (ECF), (b) early manifestation of externalizing problems, or (c) heightened levels of trait impulsivity. We test the explanatory power of(More)
OBJECTIVES Animal studies have clearly demonstrated the effects of in utero cocaine exposure on neural ontogeny, especially in dopamine-rich areas of cerebral cortex; however, less is known about how in utero cocaine exposure affects longitudinal neurocognitive development of the human brain. We used continuous arterial spin-labeling perfusion functional(More)
We assess the effects of in utero cocaine and polysubstance exposure on the adolescent caudate nucleus through high-resolution magnetic resonance imaging. Cocaine exposure may compromise the developing brain through disruption of neural ontogeny in dopaminergic systems, effects secondary to fetal hypoxemia, or altered cerebrovascular reactivity. Cocaine(More)
Preclinical studies of gestational cocaine exposure (GCE) show evidence of changes in brain function at the anatomical, physiological, and behavioral levels, to include effects on developing dopaminergic systems. In contrast, human studies have produced less consistent results, with most showing small effects or no effects on developmental outcomes.(More)
AIMS (i) To evaluate the role of pre-existing weakness in working memory ability (WM) as a risk factor for early alcohol use as mediated by different forms of impulsivity and (ii) to assess the adverse effects of progressive alcohol use on variations in WM over time. DESIGN, SETTING AND PARTICIPANTS A community sample of 358 adolescents [48% males,(More)
A time-efficient method is described for in vivo venous blood T(1) measurement using multiphase inversion-recovery-prepared balanced steady-state free precession imaging. Computer simulations and validation experiments using a flow phantom were carried out to demonstrate the accuracy of the proposed method for measuring blood T(1) by taking advantage of the(More)
BACKGROUND Concern for effects of gestational cocaine exposure (GCE) on human neurocognitive (NC) development is based on effects of cocaine on blood flow to the fetus and impact of cocaine on developing monoaminergic systems. GCE has been shown to affect language, attention and perceptual reasoning skills. OBJECTIVE Our objective was to investigate(More)
Studies of brain development suggest that the increase in risk taking observed during adolescence may be due to insufficient prefrontal executive function compared to a more rapidly developing subcortical motivation system. We examined executive function as assessed by working memory ability in a community sample of youth (n = 387, ages 10 to 12 at(More)