According to a new study, depression is tied to increased functional connectivity between a brain region that is associated with not receiving rewards and experiencing punishing events (the lateral orbitofrontal cortex) and an area of the brain involved in someone’s sense of self (the precuneus). This cutting-edge discovery was published today in the journal Brain.
For this study, 909 people (421 patients with major depressive disorder and 488 control subjects) had their brains scanned using advanced MRI neuroimaging technology. Then, the international team of researchers analyzed each person’s functional connectivity between different brain regions. The scientists were able to pinpoint specific neural networks and patterns of functional connectivity between brain regions associated with depression.
Specifically, the researchers found that depression is linked to altered connectivity within various regions of the orbitofrontal cortex (OFC). Interestingly, the medial OFC ‘reward’ systems and lateral OFC ‘non-reward’ systems change connectivity in opposite directions. These findings help to explain the neurobiological underpinnings of how depression is linked with the dejected feeling of not receiving a reward, unhappy memories, and low self-esteem.
In depression, the lateral OFC—which is associated with not getting a reward and punishing events—creates abnormally strong neural connections with other brain regions. It seems that the lateral OFC’s connection to the precuneus—a brain region involved in crystallizing your sense of self and your ability to act in your own best interest—is important. Increased functional connectivity between these brain regions backfires by exacerbating feelings of low self-esteem, hopelessness, and lack of self-worth.