Figure 2.

DPDT. a, On average, rats shifted behavior toward the punished reward as the delay increased, indicative of underestimation of delayed punishment. Each marker represents mean choice of the large reward ± SEM. b, Individual differences in DPDT performance, with each line representing a single subject. c, Percentage time spent performing locomotion during the delay period after punished and safe levers were pressed and reward was delivered. Locomotion significantly decreased after choice of the punished relative to safe reward, suggesting that rats anticipated impending shock.