Adaptive time management: The effects of death awareness on time perception and intertemporal choice

Death awareness refers to thinking about and the recognition of the inevitability of personal death. As a critical component of the human-unique ability of autonoetic consciousness, death awareness can be viewed as a cognitive adaptation for time management. We hypothesize that activating death awareness may affect intertemporal choice, in which people make tradeoffs between rewards across different time points. Such effects of death awareness on intertemporal choice may be mediated by time perception, a subjective assessment of the speed of time passage. In this research, we investigate the impact of death awareness on time perception and intertemporal choice, and the relationships among them. Study 1 examined the relationship between death awareness and time estimation. Eighty-three college students were randomly assigned to either a death awareness activation group where mortality was made salient to the participants or a control group where the participants imagined their toothache experience. After a word-search distraction task, the participants in both groups completed a time-passage (400ms, 800ms, 1200ms, 1600ms) estimation task. The results showed that the participants in the group of death awareness activation gave significantly shorter estimates than the participants in the control group. Study 2 (n = 123) extended the measure of time perception to a more extended period and also measured the delay discounting rate of the participants from their intertemporal choices between a smaller-and-sooner reward and a larger-and-later reward. The participants were randomly assigned to either a death awareness activation group or a toothache awareness activation group. The participants then indicated how long ten years was to them by marking on a line with the statement "10 years is very short" on the left end side of the line and the statement "10 years is very long" on the right end side. The participants in the death-awareness activation group marked the line closer to the left end ("life is short") than those in the control group. As predicted, the participants in the death-awareness activation group had a lower delay discounting rate and were more future-oriented in making intertemporal choices. Moreover, bootstrapping analysis revealed a partial mediation effect of time-passage estimation between death awareness and delay discounting. In conclusion, death awareness serves adaptive functions in time management. Activating death awareness makes people feel that time passes more quickly and promotes future-oriented decisions.