Capuchin monkeys (Sapajus apella) failed to seek information for their potential forgetting in a computerized task

Memory is always vulnerable to loss because it fades over time. To avoid the potential loss of a particular memory, individuals who can anticipate this loss might seek an opportunity to re-encode the information at the later point. Evidence shows that animals engage in online memory monitoring, but few studies have addressed whether they seek information prospectively to guard against potential forgetting. In the present study, to address this issue three capuchin monkeys were tested using a delayed matching-to-sample task with a cue signaling delay length (short or long). In the tests, subjects could choose at the onset of the delay whether or not to seek a re-presentation of a sample after the delay. Results showed that two monkeys sought re-presentation in the long delay more frequently than in the short delay, suggesting knowledge of the necessity of re-presentation based on knowing the length of the delay. However, further tests provided no evidence that this response was based on metacognitive cues. Whether capuchin monkeys are capable of prospective information-seeking for own potential forgetting remains to be established.