Chronic stress and anxiety can damage the brain, increase the risk of major psychiatric disorders

January 21, 2016, Baycrest Centre for Geriatric Care
Chronic stress and anxiety can damage the brain

A scientific review paper warns that people need to find ways to reduce chronic stress and anxiety in their lives or they may be at increased risk for developing depression and even dementia.

Led by the Rotman Research Institute at Baycrest Health Sciences, the review examined brain areas impacted by , fear and stress in animal and human studies that are already published. The authors concluded that there is "extensive overlap" of the brain's neurocircuitry in all three conditions, which may explain the link between chronic stress and the development of , including depression and Alzheimer's disease.

The paper is posted online this month in the journal Current Opinion in Psychiatry.

Experiencing anxiety, fear and stress is considered a normal part of life when it is occasional and temporary, such as feeling anxious and stressed before an exam or a job interview. However, when those acute emotional reactions become more frequent or chronic, they can significantly interfere with daily living activities such as work, school and relationships. Chronic stress is a pathological state that is caused by prolonged activation of the normal acute physiological stress response, which can wreak havoc on immune, metabolic and cardiovascular systems, and lead to atrophy of the brain's hippocampus (crucial for long-term memory and spatial navigation).

"Pathological anxiety and chronic stress are associated with structural degeneration and impaired functioning of the hippocampus and the prefrontal cortex (PFC), which may account for the increased risk of developing neuropsychiatric disorders, including depression and dementia," said Dr. Linda Mah, clinician scientist with Baycrest's Rotman Research Institute and lead author of the review.

The review paper examined recent evidence from studies of stress and fear conditioning in animal models, and neuroimaging studies of stress and anxiety in healthy individuals and in clinical populations.

Dr. Mah and colleagues looked specifically at key structures in the neurocircuitry of fear and anxiety (amygdala, medial , hippocampus) which are impacted during exposure to chronic stress. The researchers noted similar patterns of abnormal brain activity with fear/anxiety and - specifically an overactive amygdala (associated with emotional responses) and an under-active PFC (thinking areas of the brain that help regulate emotional responses through cognitive appraisal). This see-saw relationship was first identified in a landmark study by world-renowned neurologist and depression researcher Dr. Helen Mayberg over a decade ago.

Dr. Mah, an assistant professor of Psychiatry in the Department of Geriatric Psychiatry at the University of Toronto, concluded her review on a hopeful note by suggesting that stress-induced damage to the hippocampus and PFC is "not completely irreversible". Anti-depressant treatment and physical activity have both been found to increase hippocampal neurogenesis, she said.

"Looking to the future, we need to do more work to determine whether interventions, such as exercise, mindfulness training and cognitive behavioural therapy, can not only reduce stress but decrease the risk of developing neuropsychiatric disorders," said Dr. Mah

The scientific review paper follows on the heels of a major study Dr. Mah published in the American Journal of Geriatric Psychiatry (first posted online in October 2014), which found some of the strongest evidence yet that anxiety may accelerate conversion to Alzheimer's disease in people diagnosed with mild cognitive impairment.

Dr. Alexandra Fiocco, a psychologist with the Institute for Stress and Wellbeing Research, Ryerson University, contributed to the review paper in Current Opinion in Psychiatry. The work was supported in part by the Ministry of Health and Long-Term Care AFP Innovation Fund.

Explore further: Researchers start to understand how the environment impacts state of mind

More information: Current Opinion in Psychiatry, www.ncbi.nlm.nih.gov/pubmed/26651008

Related Stories

Researchers start to understand how the environment impacts state of mind

January 20, 2016
Anxiety disorder is the most common mental illness, affecting at least one in five adults. In their latest study, scientists at the Max Planck Institute of Psychiatry in Munich have shown that an enzyme called Dnmt3a is crucial ...

Anxiety can damage brain: Accelerate conversion to Alzheimer's for those with mild cognitive impairment

November 10, 2014
People with mild cognitive impairment (MCI) are at increased risk of converting to Alzheimer's disease within a few years, but a new study warns the risk increases significantly if they suffer from anxiety.

Overeating and depressed? Team finds connection—and maybe a solution

December 21, 2015
Chronic overeating and stress are tied to an increased risk of depression and anxiety, and in a new study, Yale researchers explain why that happens and suggest a possible solution.

Anxiety significantly raises risk for dementia

December 18, 2015
People who experienced high anxiety any time in their lives had a 48 percent higher risk of developing dementia compared to those who had not, according to a new study led by USC researchers.

Patients awaiting lung transplant commonly suffer depression-related symptoms

October 19, 2015
Researchers from Mayo Clinic in Rochester, Minnesota, have found patients awaiting lung transplant often suffer from stress, anxiety, or depressive symptoms, and these symptoms are not isolated to patients with pre-existing ...

Newly discovered windows of brain plasticity may help stress-related disorders

December 22, 2015
Chronic stress can lead to changes in neural circuitry that leave the brain trapped in states of anxiety and depression. But even under repeated stress, brief opportunities for recovery can open up, according to new research ...

Recommended for you

College students choose smartphones over food

November 16, 2018
University at Buffalo researchers have found that college students prefer food deprivation over smartphone deprivation, according to results from a paper in Addictive Behaviors.

Study finds mindfulness apps can improve mental health

November 15, 2018
A University of Otago study has found that using mindfulness meditation applications (apps) on phones is associated with improvements in people's mental health.

Social media is affecting the way we view our bodies—and not in a good way

November 15, 2018
Young women who actively engage with social media images of friends who they think are more attractive than themselves report feeling worse about their own appearance afterward, a York University study shows.

New research has revealed we are actually better at remembering names than faces

November 14, 2018
With the Christmas party season fast approaching, there will be plenty of opportunity to re-live the familiar, and excruciatingly-awkward, social situation of not being able to remember an acquaintance's name.

Older adults' abstract reasoning ability predicts depressive symptoms over time

November 14, 2018
Age-related declines in abstract reasoning ability predict increasing depressive symptoms in subsequent years, according to data from a longitudinal study of older adults in Scotland. The research is published in Psychological ...

The illusion of multitasking boosts performance

November 13, 2018
Our ability to do things well suffers when we try to complete several tasks at once, but a series of experiments suggests that merely believing that we're multitasking may boost our performance by making us more engaged in ...

0 comments

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.