Dissociative (conversion) disorders are a type of mental illness characterized by dissociative and conversion symptoms caused by obvious mental factors such as major life events, inner conflicts, emotional excitement, suggestion or self-suggestion, and the effects on susceptible individuals. Dissociative symptoms, also known as hysterical mental symptoms, refer to the partial or complete loss of self-identity recognition and memory of the past by patients, and manifested as a narrowing of consciousness, selective amnesia or mental outbursts. Conversion symptoms, also known as hysterical somatic symptoms, refer to the patient's unhappiness caused by unsolvable problems and conflicts, which is manifested in various physical symptoms. It can present symptoms similar to any disease, so some people refer to hysteria as a "great disease" or "disease imitator". It mainly manifests as various physical symptoms, narrowing of consciousness, strong suggestibility, selective amnesia or emotional outbursts and other mental symptoms, but no corresponding organic damage can be found as its pathological basis.