The areas of the brain involved in learning fears have been known, but new research now identifies the areas involved in extinguishing those fears.
“We have been able to identify neural circuits of extinction learning in humans,” said study author Elizabeth Phelps, an associate professor of psychology and neural science from New York University. “This is important, because extinction is a model we can use to look at how we get rid of fears we have learned.”
Phelps and her colleagues found the area called the amygdala is a key in both learning and unlearning fears. They also found the ventral medial prefrontal cortex is critical for the long-term extinction of fears, according to their report in the Sept. 16 issue of Neuron.
In their experiments, the researchers presented the subjects with either blue or yellow squares. One color was associated with a mild electric shock. Using this method, the subjects acquired a fear of the colored square associated with the shock.
Phelps’s team then extinguished 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.