A new study focused on the part of the brain claimed to be responsible for our kindness.
Medical Daily reports a study published in the Proceedings of the National Academy of Sciences suggests that the amygdala - which is associated with decision-making, memory and emotional processes - could be in-charge of our positive social behaviors.
"The amygdala, especially the basolateral division (BLA), has been implicated in both decision-making and social perception, inviting the possibility that it contributes to decision-making with respect to others," the researchers stated in their study. "This set of nuclei is well known for contributions to emotional experience and expression, especially fear. More recent studies demonstrate activity in BLA tracks the value of rewards and punishments, predicts risky financial decisions, reflects internal motivational goals, and correlates with vigilance and attention."
To find out how neurons in the BLA respond on social decisions, the researchers observed the social behavior of the primate species rhesus macaques - a type of monkey scientist Michael Platt has studied both in his laboratory and in the wild for 22 years.
Using an actor monkey and a receptor monkey, the researchers recorded neural activities in the amygdala to find out if its responses link to the primate's outward action. The actor monkey learned that different-colored shapes were associated with certain rewards (juice) and was given the choice of consuming it, giving it to another monkey, or ignoring it.
They specifically focused on how BLA neurons encoded the value of reward on the actor monkey when it shared its prize (the researchers discovered monkeys prefer sharing its reward to another monkey rather than not claiming or wasting it), and compared to how it encoded the value of reward when it consumed its juice.
Results show that the primate amygdala activity "reflected the value of the recipients reward in the same way it reflected the value of the reward for the actor." The "neurons in the BLA mirror the value of rewards for self and others and, moreover, these signals are correlated with prosocial decisions," the researchers wrote.
The researchers plan to conduct further studies to relate these findings to humans.
"What we're trying to do is both identify and understand the basic brain mechanism that allows us to be kind to each other and to respond to the experiences of other individuals," Platt explained. "We're also trying to use that knowledge to evaluate potential therapies that could improve the function of these neural circuits, especially for those who have difficulty connecting with others."
