The Lateral Habenula and Depression: A Review of the Role of Lateral Habenula in the Neurocircuitry of Depression

Abstract

Depression is a neurological disorder that affects a large portion of the population. While depression is identifiable and in most cases treatable, much remains to be understood about the neurocircuitry involved. This is especially true because a universally effective treatment has yet to be found. Recent evidence has pointed to the lateral habenula as a possible target for antidepressant treatment due to the role it plays in the processing of negative emotional events. The lateral habenula also has strong connections to serotonin and dopamine centers in the midbrain, which has increased speculation about the importance of its role in depression. This review finds that the lateral habenula influences serotonin and dopamine processing in the brain through a relationship with the dorsal raphe nucleus and the mesolimbic reward circuit respectively. In addition, the lateral habenula influences normal hippocampal function and provides a possible explanation for the role inflammatory agents play in depression.