A new study has investigated what instills fear in human beings.
Fear is hard coded into our neural circuitry through the amygdala, a small, almond-shaped nuclei of neurons within the medial temporal lobe of the brain.
For psychologists and neurologists, the amygdala is a particularly interesting region of the brain because it plays a role in emotional learning and can have profound effects on human and animal behavior.
A technique, developed by Dr. Fred Helmstetter and his research group at the University of Wisconsin-Milwaukee, studies how the brain responds to anticipated painful stimuli, in this case an electric shock, in volunteer test subjects.
"We're interested in how the brain reacts to stimuli in the environment and how it changes when we form a memory of what we experience." Dr. Helmstetter said.
"The amygdala is a part of the brain that's important for the way we determine what is dangerous and what is safe around us and how we react to threat. This experiment is novel in that we are able to look at activity in the amygdala on a very detailed time scale while it responds to human faces," he said.
As an emotional control center in the brain, the amygdala serves as a key component in a line of neurological structures that identify and respond to perceived threat.
Dr. Helmstetter said that, "there is good evidence to suggest that anxiety disorders and other psychopathology might be directly related to altered functioning of the amygdala."