Abbreviated fixed-interval interventions promote self-control in rats

Impulsive choice, defined as choices of a smaller-sooner reward over a larger-later reward, can be reduced by time-based interventions that expose rats to delayed rewards. These interventions improve temporal processing concurrent with reducing impulsive choice. Exposure to delayed reinforcement has produced improvements in self-control after 30 sessions of intervention exposure (Renda et al., 2021). Experiment 1 of the present study used a pre-/post-test design to investigate a range of intervention exposures (6, 15, 30, and 45 sessions), including shorter exposures that have not previously been examined. Peak-interval timing was also assessed to determine whether different intervention exposures would improve temporal processing. All intervention exposures, including the abbreviated intervention, reduced impulsive choice, and improved temporal processing. Experiment 2 showed that the 6-session intervention improved self-control relative to a no-delay control, further strengthening the proposal that an abbreviated intervention may be sufficient to reduce impulsive choice. Moreover, improvements in peak-interval timing were observed in groups receiving a pre-intervention impulsive choice assessment, suggesting that exposure to the impulsive choice task may improve temporal processing.