While both fear and anxiety can provoke an arousal response, their other effects diverge. Very intense fear sometimes serves to "freeze" the body to protect it from harm, causing little or no change in heart rate and blocking the impulse to move. In anxiety, the physical changes caused by arousal lead to a second stage marked by thought patterns such as worry, dread, and mental replays of anxiety-arousing events.
Experts have yet to agree on the root cause of anxiety disorders. In fact, most concede that several factors may be at work in each case.
An imbalance in these neurotransmitters can cause a corresponding shift in our thoughts. But is the reverse also true? Can a determined change in our thinking alter the chemistry in the brain? Many experts are convinced this is true; and behavioral therapy aimed at changing our reactions does, in fact, cure many problems. Indeed, for some disorders, such as phobias, this type of therapy remains the most effective alternative.
Prescription drugs and those purchased over the counter also can cause anxiety symptoms. Cold medicines, diet pills, antispasmodic medications, stimulants, digitalis, thyroid supplements, and, paradoxically, antidepressants given to reduce panic all may cause anxiety. Discontinuing a variety of drugs, including tranquilizers, sleeping pills, and certain blood-pressure medicines can lead to withdrawal symptoms that often include anxiety.
If you, or someone you know, has symptoms of anxiety, a visit to the family physician is usually the best place to start. A physician can help determine whether the symptoms are due to an anxiety disorder, some other medical condition, or both. Frequently, the next step in getting treatment for an anxiety disorder is referral to a mental health professional.
In addition, with new findings about neurogenesis (birth of new brain cells) throughout life, perhaps a method will be found to stimulate growth of new neurons in the hippocampus in people with post-traumatic stress disorder.