title: Earlier development of the accumbens relative to orbitofrontal cortex might underlie risk-taking behavior in adolescents.
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.
authors.affiliation: The Sackler Institute for Developmental Psychobiology, Weill Medical College of Cornell University, New York, New York 10021, USA. adg2006@med.cornell.edu
authors.forename: Adriana
authors.initials: A
authors.lastname: Galvan
authors.forename: Todd A
authors.initials: TA
authors.lastname: Hare
authors.forename: Cindy E
authors.initials: CE
authors.lastname: Parra
authors.forename: Jackie
authors.initials: J
authors.lastname: Penn
authors.forename: Henning
authors.initials: H
authors.lastname: Voss
authors.forename: Gary
authors.initials: G
authors.lastname: Glover
authors.forename: B J
authors.initials: BJ
authors.lastname: Casey
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D001931:Brain Mapping; D002648:Child; D002755:Choice Behavior / Q000502:physiology*; D005260:Female; D005625:Frontal Lobe / Q000098:blood supply / Q000502:physiology*; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D016014:Linear Models; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D009434:Neural Pathways; D009714:Nucleus Accumbens / Q000098:blood supply / Q000502:physiology*; D010100:Oxygen / Q000097:blood; D011930:Reaction Time / Q000502:physiology; D012309:Risk-Taking
chemical_list: D010100:Oxygen