In many patients, depression is associated with memory dysfunction. Now the results of a large study involving brain scans show that patients with moderate to severe depression have 7-10 per cent fewer serotonin 4 receptors in the brain than healthy test subjects.

The researchers from the University of Copenhagen, Psychiatry in the Capital Region and Rigshospitalet performed PET scans of 90 patients with depression who still had not received treatment and just as many healthy test subject of the same age. A PET scan will reveal the amount of serotonin 4 receptors in the brain.

“You cannot tell from a scan whether a person is depressed or not. But we could tell that there was a difference between the patients and the test subjects. The former had fewer serotonin 4 receptors,” says Clinical Professor Gitte Moos Knudsen from the Department of Clinical Medicine and the Neurobiological Research Unit at Rigshospitalet.

Largest PET brain scan study of its kind Previous studies have shown that the serotonin 4 receptor affects the risk of depression, while others have shown that it is associated with human memory. The new results, which have just been published in the scientific journal JAMA Psychiatry, are based on the largest PET brain scan study ever to have been conducted on patients suffering from depression. The aim of the study was to describe the connection between depression, memory dysfunction and low receptor levels.

https://jamanetwork.com/journals/jamapsychiatry/article-abstract/2801424