title: Functional neuroimaging of the Iowa Gambling Task in older adults.
abstract: OBJECTIVE
  The neural systems most susceptible to age-related decline mirror the systems linked to decision making. Yet, the neural processes underlying decision-making disparities among older adults are not well understood. We sought to identify neural response patterns that distinguish 2 groups of older adults who exhibit divergent decision-making patterns.
  
  
  METHODS
  Participants were 31 healthy older adults (ages 59-88, 53% female), defined as advantageous or disadvantageous decision-makers based on Iowa Gambling Task (IGT) performance, who completed an alternate version of the IGT while undergoing functional MRI. The groups were indistinguishable on neuropsychological testing. We contrasted the BOLD signal between groups during 3 phases of the decision-making process: Prechoice (preselection), Prefeedback (postselection), and Feedback (receipt of gains/losses). We further examined whether BOLD signal varied as a function of age in each group.
  
  
  RESULTS
  We observed greater activation among the IGT-Disadvantageous relative to -Advantageous older adults in the prefrontal cortex during the early phases of the decision-making process (Prechoice), and in posterior brain regions (e.g., the precuneus) during the later phases (Prefeedback and Feedback). We also found that with increasing age, IGT-Advantageous older adults showed increasing activation in the prefrontal cortex during all phases and increasing activation in the posterior cingulate during earlier phases of the decision process. By contrast, the IGT-Disadvantageous older adults exhibited a reduced or reversed trend.
  
  
  CONCLUSIONS
  These functional differences may be a consequence of altered reward processing or differing compensatory strategies between IGT-Disadvantageous and -Advantageous older adults. This supports the notion that divergent neurobiological aging trajectories underlie disparate decision-making patterns.
authors: Division of Cognitive Neuroscience, Department of Neurology, University of Iowa.
authors: Kameko
authors: K
authors: Halfmann
authors: Department of Marketing, University of Iowa Tippie College of Business.
authors: William
authors: W
authors: Hedgcock
authors: Institute for the Neurological Study of Emotion and Creativity, Department of Psychology, University of Southern California.
authors: Antoine
authors: A
authors: Bechara
authors: Division of Cognitive Neuroscience, Department of Neurology, University of Iowa.
authors: Natalie L
authors: NL
authors: Denburg
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001921:Brain / Q000502:physiology; D000066492:Cognitive Aging / Q000502:physiology / Q000523:psychology; D003657:Decision Making / Q000502:physiology*; D005260:Female; D059907:Functional Neuroimaging / Q000379:methods; D005715:Gambling; D006801:Humans; D007484:Iowa; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D017397:Prefrontal Cortex / Q000502:physiology*; D012201:Reward; D013647:Task Performance and Analysis