Involuntary memories of past events in non-human animals

Main area 3

It is sometimes claimed that the ability to remember past events is uniquely human and that non-human animals are unable to remember or imagine events across longer temporal distances. According to our view, however, situations with sufficiently distinctive cues should be able to spontaneously activate even remote event memories also in non-human animals, because higher order cognition is to a limited extent involved in such processes. In collaboration with researchers at Max Planck Institute for Evolutionary Anthropology and the Wolfgang Köhler Primate Research Center in Leipzig (Germany) we have recently developed a new approach to the study of spontaneous memory for simple events in non-human animals, on the basis of our insights from studying involuntary autobiographical memories in humans. (cf. Main Area 1). We found that chimpanzees and orangutans spontaneously retrieved information about a tool hiding event even after a 3 year delay, when exposed to the same spatial setup, task and experimenter, together forming a distinctive cue. The findings show that apes were able to distinguish between very similar tool-hiding events, suggesting that they were able to bind together contextual information about the different events. Thus, their memories are much more human-like than previously believed. In our future work, we use both spatial and social cues for activating memories by which we address basic dimensions in the organization of the apes’ natural environment.