Chimpanzees, just like humans, are capable of metacognition, or thinking about one's own thinking, and can adjust their behaviour accordingly, according to a new study.
Researchers at Georgia State University and colleagues found that chimpanzees share with humans the capacity for metacognitive monitoring, which reflects a form of cognitive control that underlies intelligent decision-making across species.
Researchers defined metacognition as occurring when individuals monitor what they know and don't know, when they seek information they need to know and when they respond to a question with high confidence or low confidence.
Confidence measures are one clear means of looking at how humans monitor their own knowledge states. Humans can orally report confidence or lack of confidence or even use numerical ratings scales.
The research team wanted to know if nonhuman animals show similar behavioural indications of confidence and uncertainty.
The results suggest chimpanzees show similar behaviour to humans, said Dr Michael Beran, associate director of the Language Research Center at Georgia State.
In the study, three chimpanzees were given a series of computerised tests of their memory.
The researchers could manipulate how strong or weak the chimpanzees' memories would be when they completed the test by varying the kinds of things they needed to remember and how long they needed to remember them.
After each memory test, there was a short delay before the computer programme gave feedback about whether the answer given by the chimpanzees was correct or incorrect.
A few seconds later, if the answer was correct, a food reward was delivered. The critical aspect of this study was that rewards were delivered away from where the chimpanzees worked on the memory test.
If the chimpanzees had not moved to that location when rewards were delivered, the rewards were lost and could not be recovered. This meant the chimpanzees had two options after giving an answer to the memory test.
They could either wait to hear whether the answer was correct or incorrect, and if correct, they were forced to hurry to the reward delivery location. Or, they could move to the reward location early before any feedback was provided.
The research team considered these early movements to the reward area as indications of the chimpanzees' confidence in their responses to the memory test.
Across the series of experiments, the chimpanzees consistently showed they monitored the strength of their memories and acted accordingly.
They were much more likely to move to the reward area early, before they had any feedback from the computer programme, when they gave correct answers.
The team concluded that these results, along with others, touch on the idea that chimpanzees share with humans the capacity for metacognitive monitoring.
The findings are published in the journal Cognition.
