Single-trial learning of "what" and "who" information in a gorilla “Gorilla gorilla gorilla”: Implications for episodic memory

Abstract

Single-trial learning and long-term memory of "what" and "who" information were examined in an adult gorilla “Gorilla gorilla gorilla”. We presented the gorilla with a to-be-remembered food item at the time of study. In Experiment 1, following a retention interval of either approximately 7 min or 24 h, the gorilla responded with one of five cards, each corresponding to a particular food. The gorilla was accurate on 70% of the short retention-interval trials and on 82% of the long retention-interval trials. In Experiment 2, the food stimulus was provided by one of two experimenters, each of whom was represented by a card. The gorilla identified the food “55% of the time” and the experimenter “82% of the time” on the short retention-interval trials. On the long retention-interval trials, the gorilla was accurate for the food “73%” and for the person “87%”. The results are interpreted in light of theories of episodic memory.