The region of the brain is associated with ‘non-reward’ and the physical changes have been tracked by a project run between researchers from the University of Warwick, U.K., and Fudan University, China. The effect on this brain region is said to extenuate feelings of a sense of loss and disappointment with sufferers, akin to not receiving rewards.
Research suggests that two areas of the brain have contrasting functions. The medial orbitofrontal cortex is involved in making stimulus-reward associations and with the reinforcement of behavior. In contrast the lateral orbitofrontal cortex is associated with the reversal of behavior. Specifically, activity in the lateral orbitofrontal cortex is found when subjects reach expectations about punishment and social reprisal. A physical change to this area can lock thought processes and behavior to the extent that depression arises. This can be manifest in thoughts of personal loss and low self-esteem.
The research was based on a study of around 1,000 people in China. The volunteers agreed to have their h brains scanned using high precision magnetic resonance imaging, focusing in the orbitofrontal cortex.
According to the lead scientist Professor Jianfeng Feng: “Our finding, with the combination of big data we collected around the world and our novel methods, enables us to locate the roots of depression which should open up new avenues for better therapeutic treatments in the near future for this horrible disease.”
The implications of the research are that the findings could lead to new treatments for depression. The findings are published in the journal Brain, in a paper titled “Medial reward and lateral non-reward orbitofrontal cortex circuits change in opposite directions in depression.”
In related news, Eiko Fried from the University of Amsterdam has, from a review of hundreds of cases of depression, concluded that forms of depression differ and that a one-size-fits-all approach for treatment is inappropriate; instead tailored treatment regimes work best.