Anticipation and Choice Heuristics in the Dynamic Consumption of Pain Relief

Humans frequently need to allocate resources across multiple time-steps. Economic theory proposes that subjects do so according to a stable set of intertemporal preferences, but the computational demands of such decisions encourage the use of formally less competent heuristics. Few empirical studies have examined dynamic resource allocation decisions systematically. Here we conducted an experiment involving the dynamic consumption over approximately 15 minutes of a limited budget of relief from moderately painful stimuli. We had previously elicited the participants’ time preferences for the same painful stimuli in one-off choices, allowing us to assess self-consistency. Participants exhibited three characteristic behaviors: saving relief until the end, spreading relief across time, and early spending, of which the last was markedly less prominent. The likelihood that behavior was heuristic rather than normative is suggested by the weak correspondence between one-off and dynamic choices. We show that the consumption choices are consistent with a combination of simple heuristics involving early-spending, spreading or saving of relief until the end, with subjects predominantly exhibiting the last two.Author Summary: People often have to trade-off their present wellbeing against their future wellbeing, for example whether to go to an expensive restaurant today or put the money towards a future holiday. Many studies have examined how people make such trade-offs. However, the majority have done so by analyzing choices between one-off future outcomes. By contrast, real-world choices are often made sequentially, with today’s choices influencing the possibilities available tomorrow. This generates decision problems of near limitless complexity. To explore how people approach such decisions in a naturalistic (health-related) setting, we describe participants’ use of a limited budget of relief from moderately painful stimuli over a period of approximately 15 minutes. Participants showed a range of different behaviors, with the majority either conserving relief for the future, or preferring to spread relief evenly over time. Notably no participant consistently consumed the maximum allowable relief at the outset. We show that sequential decision-making behavior cannot easily be predicted from the results of simple one-off choices made at the beginning of the task.