" It's called the fight or flight response a reaction then naturally occurs when you find yourself and dangerous situation. This isn't the only thing that happens the heart rate goes up reading patterns can change we've all been through and it's a sympathetic response. And it causes the release of open -- throughout the body. Scientists are studying what happens a brain using an MRI to see just which parts are affected by these issues. The brain actually can control the response -- the dangers perceived as real or imaginary. A wise and important. Because identifying the parts of the human brain could help uncover the problems in people with -- anxiety disorders using MRI to track the blood flow to different areas of the brain. It's a phenomenon and a way of looking at things to try and figure out whether the cortex is involved or not. For copy this or any reports from -- your health Flickr website -- was that come with your -- doctor Brian McDonough. "