According to new research which was published at the http:/www.sciencedaily.com website, scientists have gained a better understanding of how humans come to evoke a fear response.This new understanding also relates to a better understanding of the "fear circuit" in the human brain.
"These scientific researchers have discovered that a microcircuit in the amygdala that controls, or "gates," the outflow of fear from that region of the brain."
"Fear begins in your brain, and it is there -- specifically in an almond-shaped structure called the amygdala -- that it is controlled, processed and let out of the gate to kick off the rest of the fear response."
The microcircuit in question, a scientist named David J. Anderson, the Benzer Professor of Biology at Caltech and a Howard Hughes Medical Institute investigator " explains, contains two subtypes of neurons that are antagonistic -- have opposing functions -- and that control the level of fear output from the amygdala by acting like a seesaw."
"Imagine that one end of a seesaw is weighted and normally sits on a garden hose, preventing water -- in this analogy, the fear impulse -- from flowing through it," says Anderson. "When a signal that triggers a fear response arrives, it presses down on the opposite end of the seesaw, lifting the first end off the hose and allowing fear, like water, to flow." Once the flow of fear has begun, that impulse can be transmitted to other regions of the brain that control fearful behavior, such as freezing in place.
"Now that we know about this 'seesaw' mechanism," he adds, "it may someday provide a new target for developing more specific drugs for treating fear-based psychiatric illnesses like post-traumatic stress disorder, phobias, or anxiety disorders."
"The key to understanding this delicate mechanism, Anderson says, was in uncovering "markers" -- genes that would identify and allow for the scientists to discriminate between the different neuronal cell types in the amygdala. Anderson's group, led by postdoctoral fellow Wulf Haubensak, found its marker in a gene that encodes an enzyme known as protein kinase C-delta (PKCĪ“). PKCĪ“ is expressed in about half the neurons within a subdivision of the amygdala's central nucleus, the part of the amygdala that controls fear output."
Source:http://www.sciencedaily.com/releases/2010/11/101110131210.htm
This new research concering the functioning of the "fear cicuit" in the Human brain certainly gives those of us who experience anxiety some hope,that these findings may be used to find new ways or new longer-lasting or more effective medication to help us deal with these sensations which are so hard to deal with on a daily basis!
Source of image:http://www.topnews.in/health/files/Brain-circuits.jpg