Author(s)

Hengxi Liu

Corresponding Author

Hengxi Liu

ABSTRACT

Major depressive disorder (MDD) is a mental disorder that affects about 3.8% of the world population. It brings negative effect on individuals, including low mood, decreased sex desire, decreased appetite, and thought of death or suicide. Since 20th century, theories have been trying to explain the cause of major depressive disorders. Most of the theories focus on the interrelationship between social, psychological and biological causes. However, no one theory has found out the real pathopsychological causes of the diseases and treatments to this disorder are limited with medication and methods with huge side effects. The review summarizes four theories about the pathophysiology of MDD with their corresponding treatments and proposes a potential treatment of genetic approaches.

KEYWORDS

Major depressive disorder, monoamine hypothesis