Loneliness reduces the volume of gray matter in the brains of men.
- Gray matter is used to process and interpret information in the brain.
- 44% of French people feel alone, according to a new study.
- New research has just shown that loneliness reduces the volume of gray matter in the brains of men.
Loneliness has been linked to reduced gray matter volume in the brain in men, according to a new study published in the journal Cerebral Cortex. This association appears particularly strong in men with depression, while it was not observed in women.
Study author Zhenhong He and colleagues wanted to examine whether there were abnormalities in the volume of gray mass in the anterior cingulate cortex and the right ventrolateral prefrontal cortex of the brain in people with major depressive disorder. compared to the brains of healthy individuals.
The researchers also sought to determine whether loneliness was linked to structural changes in these brain regions.
The issue is essential, since the gray mass – mainly composed of neuronal cell bodies, dendrites and unmyelinated axons – is used to process and interpret information in the brain.
Gray matter and solitude: thousands of brains analyzed
In this study, brain data from men and women were analyzed and compared separately. The data comes from the database “UK Biobank”, including 21,402 people who underwent brain magnetic resonance imaging. The researchers excluded from their cohort participants with extremely low or high gray matter volumes in these regions and individuals who reported diagnoses of neurological or neurodevelopmental disorders.
The participants were classified into three categories based on the number of depressive episodes experienced or not. Loneliness was assessed on the answers to these two questions: “Do you often feel alone?” And “How often can you confide in a loved one?”
After eliminating all participants with incomplete data, the final sample for analysis included 339 men with major depressive disorder and 3,781 healthy male participants. The female sample included data from 666 people with major depressive disorder and 3,466 healthy women.
Gray matter and loneliness: 44% of French people concerned
The results showed that men with major depressive disorder had a smaller volume of gray mass in the right ventrolateral prefrontal cortex. This difference was not observed in women.
Among men with major depressive disorder, lonelier individuals tended to have smaller gray mass volume in the left and right areas of the anterior cingulate cortex and in the right ventrolateral prefrontal cortex. In healthy men, lonelier people tended to have lower volumes of gray mass in the right anterior cingulate cortex. Again, these associations did not exist in women.
“Our results demonstrate the negative effect of loneliness on brain health and the possibility that social engagement has a direct and measurable effect on brain volume in men vulnerable to depression,” conclude the authors of the study.
Loneliness is part of everyday life for the French. 44% of them admitted to feeling alone on a regular basis, according to an IFOP/Flashes survey for the animal insurer Goodflair. Among these lonely people, 18% admit to experiencing this feeling frequently, or even every day or almost.
