Earlier Development of the Accumbens Relative to Orbitofrontal Cortex Might Underlie Risk-Taking Behavior in Adolescents

The Sackler Institute for Developmental Psychobiology, Weill Medical College of Cornell University, New York, New York 10021, USA.
The Journal of Neuroscience : The Official Journal of the Society for Neuroscience (Impact Factor: 6.34). 07/2006; 26(25):6885-92. DOI: 10.1523/JNEUROSCI.1062-06.2006
Source: PubMed

ABSTRACT

Adolescence has been characterized by risk-taking behaviors that can lead to fatal outcomes. This study examined the neurobiological development of neural systems implicated in reward-seeking behaviors. Thirty-seven participants (7-29 years of age) were scanned using event-related functional magnetic resonance imaging and a paradigm that parametrically manipulated reward values. The results show exaggerated accumbens activity, relative to prefrontal activity in adolescents, compared with children and adults, which appeared to be driven by different time courses of development for these regions. Accumbens activity in adolescents looked like that of adults in both extent of activity and sensitivity to reward values, although the magnitude of activity was exaggerated. In contrast, the extent of orbital frontal cortex activity in adolescents looked more like that of children than adults, with less focal patterns of activity. These findings suggest that maturing subcortical systems become disproportionately activated relative to later maturing top-down control systems, biasing the adolescent's action toward immediate over long-term gains.

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    • "One target region for affective brain reactivity in adolescence is the ventral striatum. Recent studies have shown that neural responses in the ventral striatum to rewards are heightened during adolescence, compared to childhood and adulthood (Braams et al., 2014; Galvan et al., 2006; Van Leijenhorst et al., 2010). Especially the nucleus accumbens (NAcc), a key region for processing rewards, shows elevated responses during adolescence. "
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