Individual Differences in Delay Discounting

• DOI: 10.1111/j.1467-9280.2008.02175.x
• Publication Date: 2008-10-10T14:55:22Z
• Authors: Noah A. Shamosh; Colin G. DeYoung; Adam E. Green; Deidre L. Reis; Matthew R. Johnson; Andrew R.A. Conway; Randall W. Engle; Todd S. Braver; Jeremy R. Gray
• Keywords: Adult; Intelligence Tests; Male; Brain Mapping; Motivation; Adolescent; Culture; Intelligence; Individuality; Prefrontal Cortex; Magnetic Resonance Imaging; Young Adult; 03 medical and health sciences; Imaging, Three-Dimensional; Memory, Short-Term; 0302 clinical medicine; Adaptation, Psychological; Image Processing, Computer-Assisted; Humans; Female; Dominance, Cerebral; Internal-External Control

Lower delay discounting (better self-control) is linked to higher intelligence, but the basis of this relation is uncertain. To investigate the potential role of working memory (WM) processes, we assessed delay discounting, intelligence ( g), WM (span tasks, 3-back task), and WM-related neural activity (using functional magnetic resonance imaging) in 103 healthy adults. Delay discounting was negatively correlated with g and WM. WM explained no variance in delay discounting beyond that explained by g, which suggests that processes through which WM relates to delay discounting are shared by g. WM-related neural activity in left anterior prefrontal cortex (Brodmann's area 10) covaried with g, r = .26, and delay discounting, r = -.40, and partially mediated the relation between g and delay discounting. Overall, the results suggest that delay discounting is associated with intelligence in part because of processes instantiated in anterior prefrontal cortex, a region known to support the integration of diverse information.