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A fascinating new study from the University of Illinois at Urbana-Champaign finds that healthy adults who have a larger orbitofrontal cortex (OFC) tend to have less anxiety and are more optimistic.
This study offers the first evidence that optimism may play a mediating role in the relationship between the size of the OFC and a person's level of anxiety.
The September 2015 study, “Optimism and the Brain: Trait Optimism Mediates the Protective Role of the Orbitofrontal Cortex Gray Matter Volume against Anxiety,” was published in the journal Social, Cognitive and Affective Neuroscience. Sanda Dolcos led the research along with co-authors Yifan Hu and psychology professor Florin Dolcos.
Your orbitofrontal cortex is a brain region located in the prefrontal cortex just behind your eyes. The region has long been known to play a role in anxiety disorders. The OFC plays a central role in emotional and behavioral regulation by integrating intellectual and emotional information. Interestingly, the size of someone’s OFC appears to predict his or her susceptibility to anxiety or propensity for optimism.
The researchers set out to prove their hypothesis that being optimistic is associated with more gray matter volume in regions of the OFC. They had a hunch that a larger OFC might be part of a feedback loop that buffers anxiety by boosting optimism.
For this study, the team collected MRIs of 61 healthy young adults and analyzed the structure of a number of regions in their brains, including the OFC. Then, the researchers calculated the volume of gray matter in each brain region relative to the overall volume of the brain. Lastly, participants in the study completed tests that assessed their optimism and anxiety, depression symptoms, and positive (enthusiastic, interested) and negative (irritable, upset) affect.
Analysis of the results showed that a thicker orbitofrontal cortex on the left side of the brain corresponded to higher optimism and less anxiety. The findings also suggest that optimism played a mediating role in reducing anxiety in people with larger OFCs. Further analyses showed that no other brain structures appeared to be involved in reducing anxiety by boosting optimism.
Traumatic Events Can Shrink Parts of Your Orbitofrontal Cortex
Previously, a 2011 study compared OFC size based on brain imaging results of young adults before and after the 2011 earthquake and tsunami in Japan. The researchers, led by Atsushi Sekiguchi, discovered that the gray matter volume of the OFC atrophied in many study subjects in the months following the disaster. People who lost the most OFC volume in the left hemisphere OFC were most likely to be diagnosed with post-traumatic stress disorder (PTSD).
In a follow-up study from 2014, Sekiguchi found white matter microstuctural changes in brain connectivity in those with PTSD. Several lines of evidence supported the hypothesis that lower white matter integrity (WMI) in specific brain regions was linked to a vulnerability for anxiety disorders after stressful events. The bundle of white matter tracts was part of the "Papez Circuit," which includes connections to the amygdala.
In 2014, I wrote a Psychology Today blog post, “Chronic Stress Can Damage Brain Structure and Connectivity,” based on research which found that excessive amounts of the ‘stress hormone’ cortisol created a domino effect that hard-wired pathways between the hippocampus and amygdala in a way that increased anxiety.
The researchers from the University of California Berkeley found that chronic stress has the ability to flip a switch in stem cells that turns them into a type of cell that inhibits connections to the prefrontal cortex, but lays down durable scaffolding linked to anxiety, depression, and post-traumatic stress disorder.
Can Being Optimistic Change the Size of Your Orbitofrontal Cortex?
As an ultra-endurance athlete, I learned that consciously deciding not to be pessimistic during competition was an explanatory style and mindset that was in the locus of my control. Even when the race conditions and elements created daunting obstacles, I would consciously glom on to optimistic thoughts. I was never a Pollyanna, but I could decide to see the glass as half-full by being a "pragmatic optimist" and go faster, or I could see the glass as half-empty and go slower. The choice was mine.
In my experience, optimism always resulted in better race performances, so I learned how to guide my thoughts towards optimism. In doing so, I believe that I changed the white matter integrity and gray matter volume in various regions of my brain. This is one way that your daily athletic process can literally reshape and rewire your brain in ways that benefit your daily life.
Once I realized that negative thinking resulted in less energy, I would visualize my negative thoughts as being Teflon coated and covered in Crisco. I wouldn't let them take hold in my mind. On the flip side, my positive thoughts were covered in Velcro and super glue. I would welcome them to fill my mind and stick to various parts of my brain.
In a rudimentary way, I realize now that the positive thoughts and optimism were bulking up my OFC. Optimism may also have broken down the white matter tracks to the amygdala which gave me grace under pressure by lowering my anxiety. I know this is highly simplified neuroscience, but it works for me as a visualization. Maybe this visualization will work for you, too?
Conclusion: Optimism May Create an Upward Spiral By Changing Brain Structure
The new study by Dolcos et al shows that optimism may ultimately protect someone from anxiety by stimulating changes in the orbitofrontal cortex. It appears that someone can create an upward spiral by altering the gray matter volume of the OFC.
In future studies, Florin Dolcos plans to test whether optimism can be increased and anxiety reduced by training people in tasks that engage the orbitofrontal cortex, or by finding ways to boost optimism directly.
"You can say, 'OK, there is a relationship between the orbitofrontal cortex and anxiety. What do I do to reduce anxiety?'" Sanda Dolcos said in a press release. "And our model is saying, this is working partially through optimism. So optimism is one of the factors that can be targeted."
The researchers believe that if you can train someone to respond more positively to stressful events, and to stay optimistic on a moment-to-moment basis, that over time these explanatory styles will become embedded into his or her brain structure.
If you'd like to read more on this topic, check out my Psychology Today blog posts:
- "Optimism Stabilizes Cortisol Levels and Lowers Stress"
- "The Size and Connectivity of the Amygdala Predicts Anxiety"
- "The Neurobiology of Grace Under Pressure"
- "Why Does Having a Positive Attitude Keep You Healthier?"
- "Optimism Is Good For Your Heart"
- "Cortisol and Oxytocin Hardwire Fear-Based Memories"
- "Cortisol: Why "The Stress Hormone" Is Public Enemy No. 1"
- "Chronic Stress Can Damage Brain Structure and Connectivity"
- "One Simple Way to Improve Your Brain Function"
- "10 Keys to Happier Living Based on Self-Acceptance"
- "5 Neuroscience Based Ways to Clear Your Mind"
© 2015 Christopher Bergland. All rights reserved.
