IMPULSIVE CHOICE IN ADULTS - HOW CONSISTENT ARE INDIVIDUAL-DIFFERENCES

With animated cartoons as the reinforcer, college students repeatedly made choices between a schedule providing 15 s of viewing followed by 75 s of waiting and a schedule providing 55 s of waiting followed by 2 5 s of viewing and then 10 s of waiting. Individual differences in cho ice behavior were extreme: In the second half of the first session, on at least 70% of the trials, 40% of subjects chose the small (15-s) re inforcer (impulsivity) and 40% the large (25-s) reinforcer (self-contr ol). Each of these subjects continued to choose the same schedule cons istently throughout the second session 1 - 49 days later. A briefer sm all reinforcer (10-s) produced self-control in almost all subjects. St able individual differences could reflect an interaction between reinf orcement variables and ''personality''.