New brain imaging research suggests Sigmund Freud was correct that depression can result from exaggerated expressions of guilt and self-blame.

In a study, scientists have shown that the brains of people with depression respond differently to feelings of guilt – even after their symptoms have subsided.

Researchers found that the brain scans of people with a history of depression differed in the regions associated with guilt and knowledge of socially acceptable behavior from individuals who never get depressed.

The University of Manchester study is published in the journal Archives of General Psychiatry.

The hard evidence displayed by functional magnetic imaging (fMRI) is one of the first to show how the brain responds among people with a diagnosis of depression.

Lead researcher Roland Zahn, M.D., from the University’s School of Psychological Sciences, said: “Our research provides the first brain mechanism that could explain the classical observation by Freud that depression is distinguished from normal sadness by proneness to exaggerated feelings of guilt or self-blame.

“For the first time, we chart the regions of the brain that interact to link detailed knowledge about socially appropriate behavior – the anterior temporal lobe – with feelings of guilt – the subgenual region of the brain – in people who are prone to depression.”

Investigators used fMRI to scan the brains of a group of people after remission from major depression for more than a year, and a control group who have never had depression. Both groups were asked to imagine acting badly, for example being “stingy” or “bossy” towards their best friends. They then reported their feelings to the research team.

“The scans revealed that the people with a history of depression did not ‘couple’ the brain regions associated with guilt and knowledge of appropriate behavior together as strongly as the never depressed control group do,” said Zahn, a MRC Clinician Scientist Fellow.

“Interestingly, this ‘decoupling’ only occurs when people prone to depression feel guilty or blame themselves, but not when they feel angry or blame others. This could reflect a lack of access to details about what exactly was inappropriate about their behavior when feeling guilty, thereby extending guilt to things they are not responsible for and feeling guilty for everything.”

Scientists believe the finding is important because it reveals brain mechanisms underlying specific symptoms of depression that may explain why some people react to stress with depression rather than aggression.

Researchers are now investigating whether the results from the study can be used to predict depression risk after remission of a previous episode. Experts say that if this proves successful, then fMRI scans may be a tool to measure risk of future depression.

Source: University of Manchester