Depression
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According to a new study in the journal PLOS ONE, a UK neurology team has found that people going through a depressive episode had increased brain activity when they were asked to think about themselves.

The study team said their findings are significant because they open the door for more research and bridge the gap between psychological and neural processes.

To make their discovery, the team used functional magnetic resonance imaging (fMRI) to scan the brains of participants battling depression and a control group while they selected positive, negative and neutral adjectives to describe either themselves or the British Queen - a familiar figure chosen because of her remoteness from most people's lives.

"We found that participants who were experiencing depressed mood chose significantly fewer positive words and more negative and neutral words to describe themselves, in comparison to participants who were not depressed," said study author Peter Kinderman, a professor of psychological sciences at the University of Liverpool.

"That's not too surprising, but the brain scans also revealed significantly greater blood oxygen levels in the medial superior frontal cortex - the area associated with processing self-related information - when the depressed participants were making judgments about themselves," he added.

"This research leads the way for further studies into the psychological and neural processes that accompany depressed mood," he continued. "Understanding more about how people evaluate themselves when they are depressed, and how neural processes are involved could lead to improved understanding and care."

Dr. May Sarsam, from the Mersey Care NHS Trust, said the study effectively bridged the gap between medical and psychological theories of depression.

"It showed that brain activity only differed when depressed people thought about themselves, not when they thought about the Queen or when they made other types of judgments, which fits very well with the current psychological theory," Sarsam said. "Thought and neurochemistry should be considered as equally important in our understanding of mental health difficulties such as depression."

In their conclusion, the study author cited similar emerging studies on individuals "at risk" for depression, such as a recent study that found a positive connection between the activation of a certain section of the brain during self-referential thinking and a measure of danger for anxious and depressive disorders among young healthy participants.

"Further research in this area is needed to determine whether self-referential processing differences may constitute a vulnerability factor or mediating variable that may help explain the onset, topography, remission and recurrence of depression," the study authors wrote. "If self-referent processing is demonstrated to have a causal or mediating role in depression then such findings may contribute to the development of more precisely targeted clinical interventions."

Depression affects people universally and a new study published in PLOS Medicine found that just over 4 percent of the world's population is affected by it. The researchers zeroed in on various regions of the world and found that over 5 percent of the population suffer from depression in the Middle East, North Africa, sub-Saharan Africa, Eastern Europe and the Caribbean. The lowest levels of depression were seen in East Asia, Australia/New Zealand and Southeast Asia.