By Dr. Brian McDonough

By Dr. Brian McDonough, Medical Editor

PHILADELPHIA (CBS) – The fight or flight response is a reaction that commonly occurs when you find yourself in a stressful situation. Certain things happen physiologically like the heart rate goes up and breathing patterns can change.

Scientists call it a sympathetic response and it causes the release of epinephrine throughout the body. The brain can actually control the response if the danger is perceived as real or imaginary. And researchers are looking at what parts of the brain do this.

It is important because identifying the parts of the brain could help uncover the problems in people with anxiety disorders or other reactions to stress – real and imagined.

They are using MRIs to track the blood flow to different areas in the brain and there is hope we could have results in as little as eighteen months.