- Constant and long-term exposure to stress can cause structural and functional damages to brain and body
- Functional magnetic resonance imaging (fMRI) was used to measure localized changes in brain activation during stress
- More neuroflexibility and neuroplasticity in the ventral medial prefrontal cortex (VmPFE) helped people cope better with stress
- Absence of neuroflexibility in the VmPFC, made people cope poorly with stress. They reported binge drinking, anger outbursts, and other maladaptive coping behaviors.
"The findings from this paper add to the field by showing how the brain responds to acute stress while it is happening and unfolding," first author Rajita Sinha, PhD, the Foundations Fund Professor of Psychiatry at Yale University and director of the Yale Stress Center, in New Haven, Connecticut.
‘High neuroflexibility in certain areas of the brain, which have been identified by neuroimages from functional MRI, reveal why some people cope better with stress. Constant exposure to stress can lead to an array of health problems.’
Advertisement"These important finding points to specific brain adaptations that predict resilient responses to stress," said George F. Koob, Ph.D., director of the National Institute on Alcohol Abuse and Alcoholism (NIAAA), part of NIH and a supporter of the study. "The findings also indicate that we might be able to predict maladaptive stress responses that contribute to excessive drinking, anger, and other unhealthy reactions to stress." he added.
In a study led by Rajita Sinha, Ph.D., and Dongju Seo, Ph.D., scientists used a brain scanning technique called functional magnetic resonance imaging (fMRI) to measure localized changes in brain activation during stress. Thirty young adults who had no history of mental or physical disorders were enrolled. Functional magnetic resonance imaging fMRI were done on study participants while being exposed to highly threatening, violent and stressful images followed by exposure to neutral, non-stressful images for six successive sessions each of 60 seconds. While conducting the scans, researchers also measured their stress levels and degree of arousal. Physiological parameters like heart rate and plasma cortisol levels were measured.
The brain images revealed a sequence of three distinct patterns in response to stress, compared to non-stress exposure. The first pattern showed sustained neural activation of brain regions which helps identify and process potential threats including the amygdala, striatum, hypothalamus, and other regions. The second pattern involved increased activation, and then decreased activation, of a circuit connecting brain areas involved in stress reaction and adaptation, thought to be a mechanism of reducing the initial distress to a perceived threat. The areas included ventrolateral prefrontal cortex, the dorsal anterior cingulate cortex, the left dorsolateral prefrontal cortex, the hippocampus, and the insula. The third pattern first showed a decrease in the activation at the ventral medial prefrontal cortex (VmPFC) in response to stress, then an unexpected increase in activation with sustained stress exposure. The ventral medial prefrontal cortex is a region involved in emotional regulation and detecting one's own internal state, like hunger, craving and wanting.
This third pattern showed "neuroflexibility," in the VmPFC, a key region of dynamic and flexible neural circuit that may indicate behavioral control and active, resilient coping. "This seems to be the area of the brain which mobilizes to regain control over our response to stress," said Dr. Sinha. Such individuals would regain emotional and behavioral control to stress
People who had more neuroflexibility and neuroplasticity in this region were also less likely to be binge drinkers and emotional binge eaters, and they were less likely to respond to stress in an emotionally destructive way. The participants who showed no neuroflexibility in the VmPFC, coped poorly with stress and reported higher levels of binge drinking, anger outbursts, and other maladaptive coping behaviors. They hypothesize that such individuals might be at a higher risk for alcohol use disorder or emotional dysfunction problems, which are hallmarks of chronic exposure to high levels of stress.
Future application of the study
If these resilient coping brain circuits functioned well during stress, they helped to maintain a positive health. Promoting the resilience processes would help in the treatment and prevention of problems related to stress. If a distinct pattern for resilient and non-resilient coping is identified, it will help to classify the risk for stress-related illnesses with these brain indicators/markers. It will also help in identifying if behavioral interventions like mindfulness or cognitive-behavioral strategies like yoga and medications can improve neuroflexibility and bring back resilient coping.
Size was considered a limitation of this study. Another limitation was that fMRI images helped in identifying areas with increased activation, but did not reveal what the activation did in terms of cognitive systems. Future research is needed for better understanding of the result. The study can be used to understand the difference of stress tolerance in both sexes. Brain resilience indicator can be used as a valid marker in identifying risk for stress-related illnesses
The study was conducted by a team of researchers at Yale University, New Haven, Connecticut. Rajita Sinha, the Foundations Fund Professor of Psychiatry, director of the Yale Stress Center is the lead author of the study. Cheryl Lacadie and Todd Constable are the co-authors of the study. It was supported by the National Institutes of Health, the National Institute on Drug Abuse, and the National Institute of Diabetes and Digestive and Kidney Diseases. The findings were published in the Proceedings of the National Academy of Sciences. The National Institute on Alcohol Abuse and Alcoholism, part of the National Institutes of Health, is the primary U.S. agency for conducting and supporting research on the causes, consequences, prevention, and treatment of alcohol abuse and other alcohol related problems.
Tips for de-stressing
Some methods suggested to deal with stress include meditation, yoga, physical exercises and deep breathing techniques. Disconnecting from stressful triggers of daily life not only increases self-awareness and calms the mind, but it can also increase neuroflexibility. In 2013, researchers at the University of California in San Francisco found that when people resorted to saying 'No', they increased their stress levels. Over-commitment to work and personal life also caused stress. Omega-3 fatty acids are considered the ultimate brain food, and can be found naturally in fish as well as some plant-based foods. A 2008 study found that omega-3 fatty acids increase gray matter in the brain, and are essential to brain neuroplasticity.
- Scientists pinpoint a neural center of resilience - (http://news.yale.edu/2016/07/18/scientists-pinpoint-neural-center-resilience)
- Researchers identify brain circuits that help people cope with stress - ( https:www.nih.gov/news-events/researchers-identify-brain-circuits-help-people-cope-stress)