The results indicate that dopaminergic afferents to the OPFC contribute to the regulation of inter-temporal choice behaviour due to their role in determining organisms' sensitivity both to reinforcer size and to delay of reinforcement.

No abstract

The results indicate that lesions of the OPFC can alter inter-temporal choice, either promoting or suppressing "impulsive choice", depending upon the relative sizes and delays of the two choice alternatives. Theoretical analysis based on a quantitative model of inter-temporal choice indicates that the pattern of effect of the OPFC lesion is likely to reflect two actions: (i) an increase in the rate of time discounting; (ii) an increase in sensitivity to the ratio of the sizes of two reinforcers.