Figure 1

Main effect of DRD2 Taq I A on delay discounting. Subjective value of $100 from one week to twenty-five years for A1+ and A1- individuals. Squares show the median points of indifference for A1+; diamonds show the median points of indifference for A1- subjects. The hyperbolic curves derived from the median k values of A1+ (continuous line) and A1- groups (dotted line) are given.