title: Brain response to working memory over three years of adolescence: influence of initiating heavy drinking.
abstract: OBJECTIVE
  Many adolescents engage in heavy alcohol use. The aim of this study was to disentangle whether brain abnormalities seen in adolescent heavy drinkers are a consequence of heavy drinking, a preexisting risk factor for initiation of alcohol use, or both.
  
  
  METHODS
  Study 1 used cross-sectional functional magnetic resonance imaging (fMRI) visual working-memory (VWM) data from 15- to 19-year-olds (20 heavy drinkers, 20 controls) to identify brain regions affected by heavy adolescent alcohol use. Study 2 used longitudinal fMRI VWM data from 12- to 16-year-olds imaged before the onset of drinking and imaged again on the same scanner approximately 3 years later. Those who had transitioned into heavy drinking (n = 20) were matched to continuous nondrinkers (n = 20) on baseline alcohol risk and developmental factors (N = 40; 80 scans).
  
  
  RESULTS
  Study 1 found that heavy drinkers exhibited more frontal and parietal but less occipital activation than controls, defining the regions of interest for Study 2. In Study 2, adolescents who later transitioned into heavy drinking showed less fMRI response contrast at baseline than continuous nondrinkers, which increased after the onset of heavy drinking, in frontal (1,431 μL, p = .003; η² = .19) and parietal (810 μL, p = .005; η²= .23) regions, as in Study 1. Lower baseline activation in the frontal and parietal regions predicted subsequent substance use, more so than commonly observed predictors of youth drinking (p < .05).
  
  
  CONCLUSIONS
  Adolescents who initiated heavy drinking showed different brain activation before the onset of drinking, then less efficient information processing after high-dose alcohol use started. This suggests neural response patterns that could be risk factors for future substance use and also supports prior neuropsychological reports indicating that initiating heavy episodic drinking in adolescence may be followed by subtle alterations in brain functioning.
authors: Department of Psychiatry, University of California San Diego, San Diego, California, USA.
authors: Lindsay M
authors: LM
authors: Squeglia
authors: Carmen
authors: C
authors: Pulido
authors: Reagan R
authors: RR
authors: Wetherill
authors: Joanna
authors: J
authors: Jacobus
authors: Gregory G
authors: GG
authors: Brown
authors: Susan F
authors: SF
authors: Tapert
mesh_terms: D000293:Adolescent; D000294:Adolescent Behavior / Q000502:physiology* / Q000523:psychology; D000428:Alcohol Drinking / Q000503:physiopathology / Q000523:psychology*; D001921:Brain / Q000502:physiology* / Q000503:physiopathology; D002648:Child; D003430:Cross-Sectional Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008137:Longitudinal Studies; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008570:Memory, Short-Term / Q000502:physiology*; D010775:Photic Stimulation / Q000379:methods; D011597:Psychomotor Performance / Q000502:physiology; D012307:Risk Factors; D055815:Young Adult