Researchers have long-known rhesus monkeys cannot recognize their own reflection in the mirror, but new research suggests they can learn how to.
The discovery provides insight into the neural bases of self-awareness found in both humans and animals, a press release reported.
"Our findings suggest that the monkey brain has the basic 'hardware' [for mirror self-recognition], but they need appropriate training to acquire the 'software' to achieve self-recognition," said Neng Gong of the Chinese Academy of Sciences.
In the past researchers have
Past findings have shown that while these monkeys can learn to use mirrors to observe other objects, they could never recognize themselves. Researchers knew this because when the monkeys' faces were marked, they did not touch or examine the spot as one would if they recognized it as their own face.
In the recent study researchers set the monkey in front of a mirror and shined an irritating laser light on their faces. After between two and five weeks of training the monkeys started to touch the spot on their face that was marked with the laser, which is a major sign of self-recognition.
Five out of seven of the trained monkeys showed mirror-induced self-directed behaviors such as investigating the mark on their face. The team observed the monkeys also started using the mirrors to examine other body parts.
The findings could have important implications for individuals who are unable to recognize themselves in the mirror as a result of brain disorders such as autism and Alzheimer's disease.
"Although the impairment of self-recognition in patients implies the existence of cognitive/neurological deficits in self-processing brain mechanisms, our finding raised the possibility that such deficits might be remedied via training," the researchers wrote. "Even partial restoration of self-recognition ability could be desirable."
The findings were published in a recent edition of the journal Current Biology.
