Depressed Patients, ‘This Part’ of the Brain Is Much Larger?

A new study has found that patients with depression have significantly larger networks of specific nerve cells on the surface of their brains. This is according to a report by the Guardian, based on a paper led by researchers at Weill Cornell Medical School in the United States and published in Nature on the 4th (local time).

The surface of the brain can be thought of as a communication junction box where different areas communicate with each other to perform specific processes. However, the space that these networks can share is limited.

The researchers found that in people with depression, a network of neurons that regulate attention to reward and threat was involved in more brain regions than in people without depression. The network “occupies more space on the surface of the brain than we typically see in healthy controls,” said Charles Lynch, a professor of psychiatry at Weill Cornell Medical College, Cornell University’s medical school. When a particular brain network expands, it means that other nearby brain networks become smaller, he explained.

The researchers used a new approach to brain imaging called precise functional mapping, which analyzes multiple fMR (functional MRI) scans of each individual, to precisely measure the size of each participant’s brain networks, using 141 people with depression and 37 people without depression. They then measured the average size of the depressed and healthy controls.

As a result, they found that the brain region called the “frontostriatal salience network” was expanded by an average of 73% in the depressed participants compared to the healthy control group. These results were confirmed in a previous analysis of single brain scans collected from 932 healthy people and 299 depressed patients. The size of the network in the depressed patients did not change regardless of time, mood, or whether they received transcranial magnetic stimulation treatment, the researchers reported.

However, when participants showed specific depressive symptoms, brain signal synchronization between different parts of the prefrontal salience network was less severe. The lower synchronization rate was also associated with the severity of future depressive symptoms.

When the researchers analyzed brain scans of 57 children who developed depression in adolescence, they found that this prefrontal salience network expanded years before symptoms appeared, and that it was also expanded in adults with later onset depression. This suggests that an expansion of the prefrontal salience network may be a risk factor for developing depression rather than a consequence of depression, the researchers explained.

However, it is unclear whether the expansion of the prefrontal salience network is a result of genetics or experience, and whether the link to depression is due to this expansion or because other brain networks are smaller as a result, the researchers noted. The researchers said their findings could provide a way to explore whether certain people are at higher risk for depression and could help develop personalized treatments.

The findings could be even more helpful for people with depression, says study author Connor Liston, a professor at Weill Cornell Medical College. “It’s reassuring for some people to know that there’s something identifiable in the brain that’s associated with depression and that puts you at risk for depression,” he says.

Miriam Klein-Pluegge, a professor at Oxford University in the UK who reviewed the paper, said it was “a powerful, important and exciting study,” although she regretted that it did not address the amygdala, a key area of ​​depression research for decades. She said further research was needed to determine whether early intervention could restore the enlarged prefrontal salience network to its original size, and whether the size of this network actually predicts risk of developing depression.

The paper can be found at the following link (