Scientists have already gained ground on determining the areas of the brain related to fears and may have discovered which areas are responsible for getting rid of them.

An essential area of the brain for both learning and unlearning fears is called the amygdala. In addition, scientists have found another part of the brain known as the ventral medial prefrontal cortex, which plays an important role in the long-term extinguishing of fears. Both regions are important in understanding the brain in correlation to fear.

Scientists used a form of shock testing to make their discoveries. The subjects being tested were presented with either blue or yellow squares. One of the colors was associated with a mild electric shock. Eventually, the subject would fear the colored square resulting in a shock. Scientists then eliminated the fear response by presenting the colored square associated with the shock, first with a gradually reduced shock and then with no shock at all.

To learn the level of brain activity involved during the experiment, scientists used functional magnetic resonance imaging (fMFI) to scan the subjects' brain. This scanning measures blood flow in targeted areas of the brain through the use of harmless magnetic fields and radio signals.

Scientists discovered:

• The amygdala seems to play a vital role early on in extinction learning.

• The ventral medial prefrontal cortex is more important in retaining extinction learning.

• Understanding the part of the brain associated with fear will aid scientists in unveiling the culprit behind anxiety disorders.

• The findings can be used in developing treatments for phobias and post-traumatic stress disorder.

Scientists are confident these experiments will lead them one step further in understanding the human brain and how to rid people of fears.

Forbes September 15, 2004