a branch of psychology and medicine that studies the interaction between psychological factors and physiological processes. This field examines how emotions, psychological stress, personality types, and unconscious conflicts influence the development and progression of physical illnesses, as well as how physical illnesses, in turn, affect an individual’s psychological balance. It is an integrative domain combining psychology, medicine, neuroscience, and immunology to explain pathological phenomena within a comprehensive framework that goes beyond the traditional separation of “mind” and “body.”
The core premise is that a person is a unified, holistic being; the body and mind do not function in isolation but form an interconnected system interacting through neurological, hormonal, and immune pathways. For example, chronic psychological stress can lead to persistent activation of the hypothalamic–pituitary–adrenal (HPA) axis, resulting in increased secretion of cortisol and catecholamines. This increases the risk of cardiovascular diseases, peptic ulcers, migraines, and even immune system impairment.
The field developed in the early 20th century through the work of Franz Alexander (1930s–1950s), founder of the Chicago psychosomatic school, who linked personality traits of certain patients to the onset of specific illnesses, such as asthma and ulcers. Later, the field expanded to focus on behavioral factors and lifestyle (such as smoking, physical inactivity, and poor nutrition), as well as social determinants of health, including social support, economic stress, and social isolation.