Figure 2From: Examining impulsivity as an endophenotype using a behavioral approach: a DRD2 TaqI A and DRD4 48-bp VNTR association studyDRD2 by DRD4 interaction effect on delay discounting. Subjective value of $100 from one week to twenty-five years for individuals with each allelic combination. Median points of indifference of the four groups are provided with derived hyperbolic curves.Back to article page