Delay, probability, and effort discounting in drug addiction

Impulsivity is a core characteristic of substance abuse in that negative consequences of drug use are devalued in favor of the rewarding effects of the drug. Discounting paradigms are rooted in behavioral economics and are a common measure of impulsive decision making in the addiction literature. Delay discounting, or devaluing future rewards over immediate rewards, has been widely used to assess discounting; however less attention has been paid to other variables such as probability and effort. This chapter discusses the extant research on probability and effort discounting in relation to addiction, which has yielded mixed results and it is yet unclear how addiction relates to impulsive decisions regarding probability and effort. Here, we also discuss the current literature and provide a strong foundation for future investigations in the field of probability and effort discounting.