Washington : Brain connectivity may be behind many faces of depression such as anxiety, poor attention and concentration and disturbed sleep, says a report.

This is what University of California Los Angeles (UCLA) researchers have demonstrated for the first time in people with depression. Indeed, their brains are widely hyperconnected.

"The brain must be able to regulate its connections to function properly," said study's co-author Andrew Leuchter, professor of psychiatry at the Semel Institute for Neuroscience and Human Behaviour at UCLA, the journal Public Library of Science One reports.

"The brain must be able to first synchronize, and then later desynchronize, different areas in order to react, regulate mood, learn and solve problems," said Leuchter, according to an UCLA statement.

The depressed brain, Leuchter said, maintains its ability to form functional connections but loses the ability to turn these connections off. "This inability to control how brain areas work together may help explain some of the symptoms in depression," he said.

In the study, the largest of its kind, researchers studied the functional connections of the brain in 121 adults diagnosed with major depressive disorder, or MDD. They measured the synchronization of electrical signals from the brain, brain waves, to study networks among the different brain regions.

Brain rhythms in some of these networks regulate the release of serotonin and other brain chemicals that help control mood, said Leuchter.

"The area of the brain that showed the greatest degree of abnormal connections was the prefrontal cortex, which is heavily involved in regulating mood and solving problems," he said. "When brain systems lose their flexibility in controlling connections, they may not be able to adapt to change."