Post stroke depression is associated with changes in network of brain that involves emotional regulation, says a new study.

For the study, the researchers looked at brain scans of 24 patients between ages 18 and 80 who recently had a stroke. The brain scans were taken 10 days after stroke.

The participants were evaluated for signs of depression 10 days after the stroke and once again at 3 months after the stroke.

Ten people in the study group had mild depression while 14 people were found to be without depression.

The brain scans of the people who developed depression had modification in their DMN or default-mode network. According to the researchers, modifications in DMN have been seen in depressive patients.

"A third of patients surviving a stroke experience post-stroke depression (PSD)," said Dr. Igor Sibon, professor of neurology at the University of Bordeaux in Bordeaux, France, and the lead researcher of the study.

"However, studies have failed to identify a link between lesions in the brain caused by ischemia during a stroke and subsequent depression," Dr. Sibon said.

The brain scans of the participants were taken while they rested. Instead of looking at a specific region of the brain, the researchers looked at the entire network of emotional regulation.

"The default-mode network is activated when the brain is at rest. When the brain is not actively involved in a task, this area of the brain is engaged in internal thoughts involving self-related memory retrieval and processing," Dr. Sibon said.

Post stroke depression or PSD is a common occurrence with approximately one third of stroke survivors experiencing depression either immediately or after a few days. But, PSD often remains under-treated due to ineffective diagnosis.

Previous studies say that antidepressants might be helpful in treating people with PSD.

"We found a strong association between early resting-state network modifications and the risk of post-stroke mood disorders. These results support the theory that functional brain impairment following a stroke may be more critical than structural lesions," Dr. Sibon said.