Scientists in London believe certain parts of the brain shrink when patients are suffering from depression.
Work at the Biomedical Research Centre for Mental Health at the Maudsley Hospital with people who have clinical depression has revealed that several regions of the brain get smaller with the illness.
These include the frontal lobe, which is responsible for planning, judgement and emotions, the basal ganglia linked to movement, and the hippocampus, vital in the process of forming memories.
Researchers believe the shrinking could be caused by a hormone called cortisol which is released from the adrenal gland in response to long periods of stress.
The adrenal glands grow in sufferers of depression.
And scientists also noticed that once the depression is over, the shrinkage in the brain appears to reverse.
Dr Matthew Kempton from London’s Institute of Psychiatry said: “What we do know is these changes are definitely there in people who are depressed. What we do know is that there’s an area called the hippocampus which seems to normalise back to what people in the general population would have. So there’s some evidence to suggest that when you recover from depression at least some of these changes may go back to normal.”
Doctors hope that by using MRI scans to identify this specific shrinking in parts of the brain they will be able to identify depression more accurately, and rule out other psychiatric or neurological causes.
Scientists combined the results of multiple MRI scans on people with depression to map the changes in brain structure.
Dr Kempton added: “Once we know where these happen, perhaps what causes them, then we can look at new ways of perhaps treating illness, designing new medication for treating illness.”
Depression is thought to affect a fifth of the population at some point in their lives and it remains notoriously difficult to find the right treatment.