Intertemporal Decision-Making Involves Prefrontal Control Mechanisms Associated with Working Memory.
Intertemporal decision-making involves simultaneous evaluation of both the magnitude and delay to reward, which may require the integrated representation and comparison of these dimensions within working memory (WM). In the current study, neural activation associated with intertemporal decision-making was directly compared with WM load-related activation. During functional magnetic resonance imaging, participants performed an intermixed series of WM trials and intertemporal decision-making trials both varying in load, with the latter in terms of choice difficulty, via options tailored to each participant's subjective value function for delayed rewards. The right anterior prefrontal cortex (aPFC) and dorsolateral prefrontal cortex (dlPFC) showed activity modulation by choice difficulty within WM-related brain regions. In aPFC, these 2 effects (WM, choice difficulty) correlated across individuals. In dlPFC, activation increased with choice difficulty primarily in patient (self-controlled) individuals, and moreover was strongest when the delayed reward was chosen on the most difficult trials. Finally, the choice-difficulty effects in dlPFC and aPFC were correlated across individuals, suggesting a functional relationship between the 2 regions. Together, these results suggest a more precise account of the relationship between WM and intertemporal decision-making that is specifically tied to choice difficulty, and involves the coordinated activation of a lateral PFC circuit supporting successful self-control.
Department of Biosciences and Informatics, Keio University, Yokohama 223-0061, Japan.|Department of Psychology, Washington University, St. Louis, MO 63130, USA.
Koji
K
Jimura
Department of Psychology, Washington University, St. Louis, MO 63130, USA.
Maria S
MS
Chushak
Department of Psychology, Washington University, St. Louis, MO 63130, USA.
Andrew
A
Westbrook
Department of Psychology, Washington University, St. Louis, MO 63130, USA.|Department of Radiology, Washington University, School of Medicine, St. Louis, MO 63110, USA.
Todd S
TS
Braver
D000293:Adolescent; D000328:Adult; D065786:Delay Discounting / Q000502:physiology*; D005260:Female; D007839:Functional Laterality; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D008570:Memory, Short-Term / Q000502:physiology*; D010100:Oxygen / Q000097:blood; D017397:Prefrontal Cortex / Q000000981:diagnostic imaging / Q000502:physiology*; D011930:Reaction Time / Q000502:physiology; D012201:Reward; D055815:Young Adult
D010100:Oxygen