Monkey brains are influenced by social interactions, according to a study

The size of monkey brains are influenced by social interactions, a new study revealed, finding more friends in a group leads to larger social regions in the brain. A team of researchers from the University of Pennsylvania in Philadelphia, studied the brains, and social interactions of a group of rhesus macaques living on Cayo Santiago, an island off the coast of Puerto Rico. They found that the number of social connections predicted the size of key nodes in parts of the brain responsible for social decision-making and empathy. Though all these findings relate specifically to free-ranging rhesus macaques, they have possible implications for human behavior, in particular to understanding neuro-developmental disorders like autism, according to the team. Researchers determined that, for macaques with more grooming partners, the mid–superior temporal sulcus (STS) and ventral-dysgranular insula grew larger.