Data from: Early emergence of metacognition in rhesus monkeys

Metacognition, or monitoring and controlling one’s knowledge, is a key
feature of human cognition. Accumulating evidence shows that foundational
forms of metacognition are already present in young infants and then
scaffold later-emerging skills. While many animals exhibit cognitive
processes relevant to metacognition, it is unclear if other species share
the developmental trajectories found in human development. Here, we
examine the emergence of metacognitive information-seeking in rhesus
monkeys (Macaca mulatta). We presented a large sample of semi-free-ranging
monkeys, ranging from juvenility to adulthood, with a one-shot task where
they could seek information about a food reward by bending down to peer
into a center vantage point in an array of tubes. In the hidden condition,
information-seeking was necessary as no food was visible on the apparatus,
whereas in the visible control condition information-seeking was not
necessary to detect the location of the reward. Monkeys sought information
at the center vantage point more often when it was necessary than in the
control condition, and younger monkeys already showed competency similar
to adults. We also tracked additional monkeys who voluntarily chose not to
approach to assess monkeys’ ability to actively infer opportunities for
information-seeking, and similarly found similar performance in juveniles
and adults. Finally, we found that monkeys were overall slower to make
metacognitive inferences than to approach known rewards, and that younger
monkeys were specifically slower to detect opportunities for
information-seeking compared to adults. These results indicate that many
features of mature metacognition are already detectable in young monkeys,
paralleling evidence for ‘core metacognition’ in infant humans.