Meaningful social interactions are essential to an individual’s well-being, and such interactions are based on people’s behaviors towards each other.
In research published in Science, researchers at Massachusetts General Hospital (MGH) mapped neurons in the brain that allow one monkey to process and remember the interactions and behaviors of another monkey to influence the animal’s own actions. The results could be used to develop treatment strategies for people with neuropsychiatric disorders.
The study had three rhesus monkeys sit around a turntable and take turns offering an apple slice to one of the other two monkeys. At the same time, the researchers recorded the activity of individual neurons in an area of the brain known to play a role in social cognition, called the dorsomedial prefrontal cortex (dmPFC).
During these interactions, the monkeys reciprocated past offerings of one apple slice and fought back when they were not given a slice from another. The researchers’ recordings identified distinct neurons in dmPFC that responded to the actions of the other monkeys in the group.
Certain neurons have been activated with a particular action and result of specific individuals within the group (such as a neighboring monkey offering an apple slice leads to the result of receiving the reward). Many neurons have encoded information not only about the actions and results of specific individuals, but also about their past behavior.
This information about past interactions with group members influenced an animal’s future decisions to reciprocate or fight back, and investigators could use the neural information to predict which monkey would receive an apple slice from a monkey. particular before it is even offered.
This finding suggests that dmPFC plays a role in strategic decisions. To test this idea, we disrupted normal activity in this area and found that animals were less likely to reciprocate.. “
Raymundo Báez-Mendoza, PhD, lead study author and researcher, Department of Neurosurgery, Massachusetts General Hospital
The results suggest that dmPFC plays an important role in mapping our actions and outcomes as well as the actions of others. “In neuropsychiatric conditions in which this ability is compromised, treatments aimed at improving the functioning of this area of the brain, directly or indirectly, could improve people’s lives,” says lead author Ziv Williams, MD.