Individual differences in the connectivity between regions of the brain involved in fear and anxiety are heritable, according to a large study of hundreds of related monkeys published in JNeurosci. The research provides new insights into the risk and development of anxiety disorders.
Authors previously demonstrated that metabolism in the central extended amygdala (EAc)—including the central nucleus of the amygdala (Ce) and bed nucleus of the stria terminalis (BST)—is associated with trait-like variation in AT.
Using brain imaging techniques regularly employed in human studies, researchers found that functional connectivity between two regions of the central extended amygdala is associated with anxious temperament (AT) in pre-adolescent rhesus macaques.
Results demonstrate that Ce-BST functional connectivity is heritable, accounts for a significant but modest portion of the variance in AT and is co-heritable with AT. Interestingly, Ce-BST functional connectivity and AT-related BST metabolism were not correlated and accounted for non-overlapping variance in AT. Exploratory analyses suggest that Ce-BST functional connectivity is associated with metabolism in the hypothalamus and periaqueductal gray.
Together these results suggest the importance of coordinated function within the EAc for determining individual differences in AT and metabolism in brain regions associated with its behavioral and neuroendocrine components.
As extreme early-life anxiety is a risk factor for anxiety disorders and depression in humans, further study of this nonhuman primate model may yield new directions in the prevention of these disorders in at-risk children. This would represent an improvement over current treatments, which address symptoms rather than the mechanisms underlying the development of these disorders.
Is anxiety heritable?
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