Monkeys can make judgments based on memory and be confident about their strategic choices, according to a study released Friday.
Researchers from Juntendo University and Tokyo University tested to see if "metamemory" — the ability to monitor one's memories, a process that is characteristic of humans — affected how confident macaque monkeys were in responding to prior stimuli, according to the study, published in the U.S. journal Science.
The monkeys were shown four graphics and later were tested to see if they could identify those images among others.
The researchers also tested to see how confident the primates were about their answers. The monkeys were presented with two choices tied to rewards. In the "high bet," the reward was greater — a lot of juice — if the answer was correct but was nothing if incorrect. The other choice was the "low bet," which rewarded the monkey with smaller amounts of juice regardless of whether or not the answer was correct.
The study found the monkeys "more frequently chose 'high bets' when they correctly answered the precedent test than when they failed it," the researchers wrote, indicating that when the monkeys were confident about their answers based on what they remembered, they would strategically choose the high-bet option.
Yasushi Miyashita, the team's leader, said the finding "could be helpful in the diagnosis and treatment of memory-related disability, as well as development of a new method for education."