_ «Study authors then looked at the volume of the amygdala, controlling for the size of the overall brain, in each participant. The relative size of the amygdala was not associated with perceived social support, satisfaction with social interactions, or how much participants enjoy interacting with people in general. It did, however, correlate well with the size and complexity of individuals' social networks.
The association between amygdala size and social network size and complexity appeared fairly consistent among men and women, and among old and young participants.
Because the study does not show causation, it is impossible to know whether the amygdala actually grows in size because of social interaction, or if people with larger amygdalae gravitate toward larger groups of friends, or both. This study cannot make conclusions about that topic, but it is the subject of ongoing research.» _
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