A little bit of fear protects us from danger, but too much can cause serious psychological discomfort and, in some cases, mental health problems. New research uncovers the brain circuit involved in processing fear, which could eventually lead to new treatment options for people with mental health disorders.

Share on Pinterest New research investigates how different areas of the human brain are involved in its response to fear.

From an evolutionary perspective, fear and anxiety are quite useful. These deeply ingrained emotions used to protect our ancestors from predators, and in our times the “fight-or-flight” response is still a healthy reaction to dangerous situations.

When fear is proportionate to the danger a person is in, it is a normal, adaptive response. However, some of us have exaggerated reactions to stressful situations.

As the National Institute of Mental Health explains, when the fear response is disproportionate or lasts a lot longer than what is normally expected from the situation – to a point where it interferes with an individual’s well-being and daily functioning – it is classed as an anxiety disorder.

Anxiety disorders include a wide range of conditions that reportedly affect 18 percent of the adult population in the United States.

Because we share some of the brain’s architecture with our fellow mammals and we have a similar response to fear, studying animal models has provided scientists with important insights into the neuroscientific basis for fear processing.

So far, animal studies have shown that the amygdala is a key player in fear processing, and that the hippocampus also plays a significant role in forming memories of emotional events.

However, researchers from the University of California-Irvine (UCI) believe that this body of research has not sufficiently investigated how the two regions interact in the presence of a fearful stimulus.

This is why the scientists – led by Dr. Jack Lin, a professor of neurology at UCI – set out to examine the neural pathways involved in fear and anxiety processing in humans.

The findings were published in the journal Nature Communications.