Future thinking improves prospective memory performance and plan enactment in older adults

Abstract

Efficient intention formation might improve prospective memory by reducing the need for resource-demanding strategic processes during the delayed performance interval. The present study set out to test this assumption and provides the first empirical assessment of whether imagining a future action improves prospective memory performance equivalently at different stages of the adult lifespan. Thus, younger (n = 40) and older (n = 40) adults were asked to complete the Dresden Breakfast Task, which required them to prepare breakfast in accordance with a set of rules and time restrictions. All participants began by generating a plan for later enactment; however, after making this plan, half of the participants were required to imagine themselves completing the task in the future (future thinking condition), while the other half received standard instructions (control condition). As expected, overall younger adults outperformed older adults. Moreover, both older and younger adults benefited equally from future thinking instructions, as reflected in a higher proportion of prospective memory responses and more accurate plan execution. Thus, for both younger and older adults, imagining the specific visual–spatial context in which an intention will later be executed may serve as an easy-to-implement strategy that enhances prospective memory function in everyday life.

Keywords:

• Ageing
• Prospective memory
• Future thinking
• Planning
• Imagery

Notes

¹Piloting indicated that some older adults found it difficult to operate the computer mouse. Thus, to control for possible effects of differences in computer experience between the two groups, participants did not operate the computer mouse by themselves. Instead, all participants moved their index finger across the screen and the experimenter followed with the mouse. To avoid any social influence during the computer tasks, the researcher sat behind the participants, and further conversations were not allowed. Participants seemed to respond as if they were using a touch screen rather than directing the experimenter (e.g., if response to touching of the screen was slow, they would tend to retouch the screen rather than look at the experimenter).

²Pilot studies with participants across the lifespan indicated that time frames of ±60 s for time-based tasks and of 30 s after presentation of the cue for event-based tasks were adequate time ranges to allow for sufficient variance in performance between participants. The lower cut-off points for event-based tasks than for time-based tasks are associated with their rather high salience (e.g., beeping of egg cooker; clicking sound plus change of colour of kettle).