Adaptive memory: fitness relevant stimuli show a memory advantage in a game of pelmanism

Abstract

A pelmanism (matched-pairs) game was used in order to test the hypothesis that survival-relevant stimuli that are likely to have been present during human evolution (e.g. a snake in attack position) enjoy a memory advantage over other survival-relevant (but “modern”) stimuli (e.g. a threatening image of a gunman). Survival-relevant stimuli were matched for arousal, and presented in one of two 5x4 grids along with filler items. Participants were asked to match the pairs in the grids by clicking on successive squares to reveal stimuli. Participants made significantly fewer errors when matching “evolutionarily relevant” survival stimuli compared to other stimuli. Additionally, on incorrect trials, attempted matches were significantly closer to the location of evolutionarily relevant targets than for other stimuli. Results suggest that objects which likely posed a consistent threat throughout human evolutionary history are better remembered than other, equally arousing and survival relevant, stimuli.