Decision making, impulsivity and time perception

Time is an important dimension when individuals make decisions. Specifically, the time until a beneficial outcome can be received is viewed as a cost and is weighed against the benefits of the outcome. We propose that impulsive individuals experience time differently, that is with a higher cost. Impulsive subjects, therefore, overestimate the duration of time intervals and, as a consequence, discount the value of delayed rewards more strongly than do self-controlled individuals. The literature on time perception and impulsivity, however, is not clear cut and needs a better theoretical foundation. Here, we develop the theoretical background on concepts of time perception, which could lead to an empirically based notion of the association between an altered sense of time and impulsivity.

Introduction

The perception of time is a crucial factor when individuals have to make decisions and consider the outcomes associated with their choices. Rewards that are received sooner are often preferred over future rewards, that is the subjective value of an outcome is discounted as a function of the delay 1, 2. It is well known that impulsive subjects devalue temporally delayed rewards more strongly than do comparison subjects, and this behavior might be due to their altered sense of time. According to this hypothesis, impulsive individuals will opt for smaller and immediate rewards more often than for delayed but higher rewards because they estimate duration as being subjectively longer than do more self-controlled individuals. The perception of time as lasting too long is associated with too high of a cost, which leads to the selection of alternatives with more immediate outcomes (see Figure 1).

Several empirical studies pointing to a possible association among impulsivity, decision making and time perception have been conducted over the last few decades 3, 4, 5, 6, 7, 8. However, only recently has this notion been addressed in a more systematic way. Here, we develop a conceptual framework that can guide current and future research and might allow researchers to build a consistent theory framing impulsivity, decision making and the experience of time. We will point to some methodological factors that have to be controlled for to reach valid conclusions and to explain impulsive decision making in inter-temporal choices. First, findings will be reviewed on impulsive behavior in inter-temporal choices, particularly in delay-discounting tasks, which examine the influence of time on decision making. Second, cognitive models of time perception will be related to study results showing that impulsive subjects display an altered sense of subjective time. It will be argued that the association between time perception and mood states plays a fundamental role in interpreting these empirical results.