Depression may result in structural changes to the brain, according to a new major scanning study conducted by scientists at the University of Edinburgh in Scotland.
In people with depression, the researchers found differences in the brain’s white matter, a part of the brain which contains fiber tracts that allow brain cells to communicate with one another by electrical signals. White matter is an important component of the brain’s wiring, and its disruption has been associated with problems in emotion processing and thinking skills.
The findings shed light on the biology of depression and could help in the search for better diagnosis and treatment.
For the study, the researchers used a cutting-edge technique known as diffusion tensor imaging to map the structure of white matter. They discovered that the quality of the matter — known as white matter integrity — was reduced in participants who reported symptoms indicative of depression. The same changes were not seen in people who did not have depressive symptoms.
Participants were drawn from UK Biobank, a national research resource with health data available from 500,000 volunteers. Experts say the high number of people included in the sample (3,461 participants) means that the study findings are very robust.
“This study uses data from the largest single sample published to date and shows that people with depression have changes in the white matter wiring of their brain,” said Heather Whalley, a senior research fellow at the University of Edinburgh’s Division of Psychiatry.
“There is an urgent need to provide treatment for depression and an improved understanding of it mechanisms will give us a better chance of developing new and more effective methods of treatment. Our next steps will be to look at how the absence of changes in the brain relates to better protection from distress and low mood.”
Depression is the world’s leading cause of disability. In 2015, approximately 16.1 million adults aged 18 or older in the United States had at least one major depressive episode in the past year, according to the National Institute of Mental Health (NIMH). This number represented 6.7% of all U.S. adults.
Symptoms of depression may include low mood, exhaustion, apathy, loss of appetite, insomnia, guilt, and/or feelings of emptiness.
The study forms part of a Wellcome Trust initiative called Stratifying Resilience and Depression Longitudinally (STRADL), which aims to classify subtypes of depression and identify risk factors.
The findings are published in the journal Scientific Reports.
Source: University of Edinburgh