Learning to wait for more likely or just more: greater tolerance to delays of reward with increasingly longer delays.

Little research has focused on training greater tolerance to delays of rewards in the context of delayed gratification. In delayed gratification, waiting for a delayed outcome necessitates the ability to resist defection for a continuously available smaller, immediate outcome. The present research explored the use of a fading procedure for producing greater waiting in a video-game based, delayed gratification task. Participants were assigned to conditions in which either the reward magnitude, or the probability of receiving a reward, was a function of time waited and the delay to the maximum reward was gradually increased throughout this training. Waiting increased for all participants but less for those waiting for a greater reward magnitude than a greater reward probability. All participants showed a tendency to wait in a final testing phase, but training with probabilistic outcomes produced a significantly greater likelihood of waiting during testing. The behavioral requirements of delay discounting versus delay gratification are discussed, as well as the benefits of training greater self-control in a variety of contexts.