Academic journal article The Psychological Record

Relation between Time Perspective and Delay Discounting: A Literature Review

Academic journal article The Psychological Record

Relation between Time Perspective and Delay Discounting: A Literature Review

Article excerpt

Recently there has been an increasing level of interest in delay discounting, that is, the process of devaluing outcomes that occur in the future (e.g., Ainslie, 1974; Logue 1988; Rachlin & Green, 1972; for a review, see Green & Myerson, 2004). This process can be used to explain the observation that individuals will sometimes choose a smaller, more quickly available reward rather than a larger reward available later. Such choices have been thought of as impulsive or rash because waiting would result in a larger reward. Given the link between delay discounting and impulsive behavior, it is unsurprising that part of the interest in delay discounting is driven by the growing literature linking higher levels of discounting, and presumably heightened delay aversion, to a number of psychiatric diagnoses, for example, drug addiction, attention-deficit/hyperactivity disorder, and schizophrenia (see array of chapters in Madden & Bickel, 2010, for reviews). A number of researchers have suggested that heightened delay discounting is synonymous with having a foreshortened time horizon and considering only a limited period into the future (e.g., Petry, Bickel, & Arnett, 1998; Rachlin, Siegel, & Cross, 1994).

Although the literature is not specific about how these constructs interact, the use of the term horizon is somewhat at odds with the well established discounting function in which the subjective value of an outcome declines smoothly as the delay increases. Rather, a horizon conceptualization would suggest a stepwise function for individuals, or at least that the value of a delayed item should decrease precipitously once the delay exceeds the individual's time horizon. Such an implied discontinuity in the delay discounting function has not been empirically observed. Proponents of a conceptual linkage between the two constructs might argue that the use of widely spaced delays in the typical discounting paradigm makes it difficult to see discontinuities. Further, they might explain the discounting function tending to an asymptote rather than falling to a predicted level of zero as being due to participants being reluctant to value a delayed reward as negligible. Research addressing these explanations would be useful. Nevertheless, it is important to examine the level of overlap between the constructs of delay discounting and time horizon (also known as future time perspective) because there is a large literature on each, which might suggest novel research directions if there proves to be a significant level of overlap.

To explore the extent of overlap between delay discounting and future time perspective, we first briefly examine how each has been defined and quantified so as to then assess their relative conceptual similarity. We also examine relative similarity suggested by studies in which both delay discounting and future time perspective have been measured and compare variables associated with variations in time horizon and in delay discounting. Measures of future time perspective can only be assessed in human participants, and for that reason the vast and interesting literature in which delay discounting has been studied in nonhuman animals will be ignored.

Measures and Conceptualizations of Delay Discounting and Future Time Perspective

As reviewed by Madden and Johnson (2010), delay discounting is ordinarily measured by examining the preference between a small reward available immediately or soon versus a larger reward available at a later time. By varying the amount of the sooner reward, researchers can identify the point at which study participants value the larger, later reward. Alternatively, by varying the length of the delay to the larger reward, researchers can obtain a series of values to describe the change in value of the larger, delayed reward as a function of delay length. Studies with humans have assessed discounting for delays ranging in length from minutes to years. …

Search by... Author
Show... All Results Primary Sources Peer-reviewed

Oops!

An unknown error has occurred. Please click the button below to reload the page. If the problem persists, please try again in a little while.