Washington, Dec 27 (IANS) The size of amygdala, a small almond-shaped structure deep within brain, seems to contribute to a rich social life among humans.
The finding is similar to previous ones in other primate species, which compared the size and complexity of social groups across those species, the journal Nature Neuroscience reports.
‘We know that primates who live in larger social groups have a larger amygdala,’ says Lisa Feldman Barrett, psychology professor at Northeastern University, in the US, who led the study.
Barrett is also part of the Massachusetts General Hospital (MGH) Psychiatric Neuroimaging Research Program.
‘We considered a single primate species, humans, and found that the amygdala volume positively correlated with the size and complexity of social networks in adult humans,’ she said, according to Massachusetts release.
‘This link between amygdala size and social network size and complexity was observed for both older and younger individuals and for both men and women,’ says Bradford C. Dickerson, study co-author and associate professor of neurology at Harvard Medical School.
Researchers asked 58 participants to report about the size and the complexity of their social networks by filling in questionnaires that measured the total number of regular social contacts that each of them maintained.
Participants, aged between 19 and 83 years, also received a magnetic resonance imaging brain scan to gather information about the various brain structures, including the volume of the amygdala.