Somatic symptom disorder (SSD formerly known as somatization disorder or somatoform disorder ) is a form of mental illness that causes one or more bodily symptoms, including pain. 1 Introduction Somatization is generally defined as the experiencing and communicating of psychological distress as physical symptoms or conditions for which a physical aetiology cannot be readily demonstrated, and seeking medical help. When mental factors such as stress cause physical symptoms the condition is known as somatisation. Somatoform disorders are a severe form of somatisation. Somatization is the expression of mental phenomena as physical (somatic) symptoms. Disorders characterized by somatization extend in a continuum from those in which symptoms develop unconsciously and nonvolitionally to those in which symptoms develop consciously and volitionally. Somatization is the generation of somatic symptoms due to psychological distress, often coinciding with a tendency to seek medical help for them. [1][2] The term somatization was introduced by Wilhelm Stekel in 1924. Two distinct ways of looking at somatization can be distinguished: somatization as a phenomenon that is secondary to psychological distress (presenting somatization) and somatization as a primary phenomenon characterized by medically unexplained symptoms (functional somatization). Somatization is the expression of mental experiences into physical responses. Somatic symptom disorder (SSD) is a psychiatric disorder characterized by an obsession with unexplained physical symptoms, commonly physical pain, which cannot be explained by medical disorders. Somatization is the expression of mental or emotional distress as physical symptoms in the body. You might experience real, measurable pain, fatigue, or digestive trouble, but the driving force behind those symptoms is psychological rather than a structural injury or disease. Somatization refers to the process by which psychological distress is expressed through physical symptoms without an identifiable organic cause. It represents a complex interaction between mind and body, where emotional or mental conflict manifests as bodily complaints. Overview Somatic symptom disorder involves focusing too much on physical symptoms such as pain or tiredness. This focus causes major emotional distress and makes it hard to function. You may or may not have another medical condition that causes these symptoms. But how you think, feel and behave because of the symptoms can be extreme.