WHAT IS fMRI: Magnetic resonance imaging (MRI) uses radio waves and a strong magnetic field rather than X-rays to take clear and detailed pictures of internal organs and tissues. fMRI uses this technology to identify regions of the brain where blood vessels are expanding, chemical changes are taking place, or extra oxygen is being delivered. These are indications that a particular part of the brain is processing information and giving commands to the body. As a patient performs a particular task, the metabolism will increase in the brain area responsible for that task, changing the signal in the MRI image. So by performing specific tasks that correspond to different functions, scientists can locate the part of the brain that governs that function.
FIGHT OR FLIGHT: Certain events act as "stressors," triggering the nervous system to produce hormones to respond to the perceived danger. Specifically, the adrenal glands produce more adrenaline and cortisol, releasing them into the bloodstream. This speeds up heart and breathing rates, and increases blood pressure and metabolism. These and other physical changes help us to react quickly and effectively under pressure. This is known as the "stress response," or more commonly, as the "fight or flight response." But if even low levels of stress go on too long, it can be detrimental to one's health. The nervous system remains slightly activated and continues to pump out extra stress hormones over an extended period, leaving the person feeling depleted or overwhelmed, and weakening the body's immune system.
STRESS-REDUCING TIPS: There are several easy, practical things people can do to reduce the amount of stress in their lives. (1) Be realistic and don't try to be perfect, or expect others to be so. (2) Don't over-schedule; cut out an activity or two when you start to feel overwhelmed. (3) Get a good night's sleep. (4) Get regular exercise to manage stress -- just not excessive or compulsive exercise -- and follow a healthy diet. (5) Learn to relax by building time into your schedule for reading or a nice long bath.