Chinks in the brain circuitry make some more vulnerable to anxiety

Feb 10, 2011 By Yasmin Anwar

(PhysOrg.com) -- Why do some people fret over the most trivial matters while others remain calm in the face of calamity? Researchers at the University of California, Berkeley, have identified two different chinks in our brain circuitry that explain why some of us are more prone to anxiety.

Their findings, published today (Wednesday, Feb. 9) in the journal Neuron may pave the way for more targeted treatment of chronic fear and . Such conditions affect at least 25 million Americans and include panic attacks, social phobias, obsessive-compulsive behavior and post-traumatic stress disorder.

In the brain imaging study, researchers from UC Berkeley and Cambridge University discovered two distinct that play a role in whether we develop and overcome fears. The first involves an overactive amygdala, which is home to the brain’s primal fight-or-flight reflex and plays a role in developing specific phobias.

The second involves activity in the ventral prefrontal cortex, a neural region that helps us to overcome our fears and worries. Some participants were able to mobilize their ventral prefrontal cortex to reduce their fear responses even while negative events were still occurring, the study found.

“This finding is important because it suggests some people may be able to use this ventral frontal part of the brain to regulate their fear responses – even in situations where stressful or dangerous events are ongoing,” said UC Berkeley psychologist Sonia Bishop, lead author of the paper.

“If we can train those individuals who are not naturally good at this to be able to do this, we may be able to help chronically anxious individuals as well as those who live in situations where they are exposed to dangerous or stressful situations over a long time frame,” Bishop added.

Bishop and her team used functional Magnetic Resonance Imaging (fMRI) to examine the brains of 23 healthy adults. As their brains were scanned, participants viewed various scenarios in which a virtual figure was seen in a computerized room. In one room, the figure would place his hands over his ears before a loud scream was sounded. But in another room, the gesture did not predict when the scream would occur. This placed volunteers in a sustained state of anticipation.

Participants who showed overactivity in the developed much stronger fear responses to gestures that predicted screams. A second entirely separate risk factor turned out to be failure to activate the ventral prefrontal cortex. Researchers found that participants who were able to activate this region were much more capable of decreasing their fear responses, even before the screams stopped.

The discovery that there is not one, but two routes in the that lead to heightened fear or anxiety is a key finding, the researchers said, and it offers hope for new targeted treatment approaches.

“Some individuals with anxiety disorders are helped more by cognitive therapies, while others are helped more by drug treatments,” Bishop said. “If we know which of these neural vulnerabilities a patient has, we may be able to predict what treatment is most likely to be of help.”

Explore further: 'Trigger' for stress processes discovered in the brain

Related Stories

Neural mechanisms linked with vulnerability to anxiety

Feb 09, 2011

New research examines the anxious brain during a fear conditioning task and provides insight into why some individuals may be more or less prone to anxiety disorders. The study, published by Cell Press in the February 10 ...

Individuals with social phobia see themselves differently

Oct 06, 2008

Magnetic resonance brain imaging reveals that patients with generalized social phobia respond differently than others to negative comments about themselves, according to a report in the October issue of Archives of General Ps ...

New insights into the neural basis of anxiety

Jun 03, 2007

People who suffer from anxiety tend to interpret ambiguous situations, situations that could potentially be dangerous but not necessarily so, as threatening. Researchers from the Mouse Biology Unit of the European Molecular ...

Recommended for you

'Chatty' cells help build the brain

3 hours ago

The cerebral cortex, which controls higher processes such as perception, thought and cognition, is the most complex structure in the mammalian central nervous system. Although much is known about the intricate ...

'Trigger' for stress processes discovered in the brain

18 hours ago

At the Center for Brain Research at the MedUni Vienna an important factor for stress has been identified in collaboration with the Karolinska Institutet in Stockholm (Sweden). This is the protein secretagogin ...

New research supporting stroke rehabilitation

Nov 26, 2014

Using world-leading research methods, the team of Dr David Wright and Prof Paul Holmes, working with Dr Jacqueline Williams from the Victoria University in Melbourne, studied activity in an area of the brain ...

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.