Prefrontal cortex- bdělost , stres

[ATA]

Notes:

prefrontal cortex of the brain normally “gets a grip” on excessive anxiety by moderating the activity of a more primitive region known as the amygdala. When this prefrontal-amygdala connection is weak, excessive anxiety can be the result.

The scientists found that when 20 healthy subjects watched standard test images of “fearful” faces, brain activity increased on the fMRI scans. The increases seemed to map to a nerve-fiber bundle known as the uncinate fasciculus (UF)—a major connection between the temporal lobe, which houses the amygdala, and the frontal cortex.

The researchers also found that the thickness of this fiber tract varied inversely with the subjects’ scores on a standard psychological test of inherent anxiety, known as trait anxiety. “So if the two areas are strongly connected, you tend to show lower levels of [the] trait anxiety, and if the connections aren’t as heavy, you tend to be more anxious,” Whalen says.

moderating influence on the simpler, more impulsive and less flexible structures of the limbic system, which humans share with other mammals.

“The prefrontal cortex is supposed to keep areas like the amygdala in check, and instruct them that, for example, ‘I know that’s a snake, but it’s behind a piece of plexiglass, so we’re good,’” Whalen says. “It’s much like a parent and child. Children are less flexible in their responses to situations than parents, whose job is to instruct them and help them regulate.”