Anxiety is an emotion characterized by nervous behavior. A new study by researchers from University of Wisconsin-Madisonon has revealed that anxious parents are more likely to have anxious children, and the risk of developing anxiety and depression is passed from parents to children.
The researchers said, "An over-active brain circuit involving three brain areas inherited from generation to generation may set the stage for developing anxiety and depressive disorders." Senior study author Ned Kalin said, "Over-activity of these three brain regions are inherited brain alterations that are directly linked to the later life risk to develop anxiety and depression."
The study findings suggest that elevated activity in the brain areas is likely involved in mediating the in-born risk for extreme anxiety and anxious temperament that can be observed in early childhood. Like humans, even monkeys can be temperamentally anxious and pass their anxiety-related genes on to the next generation.
By studying nearly 600 young rhesus monkeys, the research team found that about 35% of variation in anxiety-like tendencies is explained by family history. To a certain extent, anxiety provides an evolutionary advantage because it helps an individual recognize and avoid danger.
Kalin further explained, "But when the circuits are over-active, it becomes a problem and can result in anxiety and depressive disorders."
Surprisingly, the team found that it was the function of brain structures, and not their size, that was responsible for the genetic transfer of an anxious temperament. Kalin noted, "Now that we know where to look, we can develop a better understanding of the molecular alterations that give rise to anxiety-related brain function." The findings are a big step in understanding the neural underpinnings of inherited anxiety and begins to give researchers more selective targets for treatment.
The study appeared in the Proceedings of the National Academy of Sciences (PNAS).