Schizophrenia is a group of common severe psychiatric disorders of unknown etiology, mostly with a slow or subacute onset in young adults, often manifesting clinically as psychiatric syndromes with varying symptoms involving multiple impairments in perception, thinking, emotion and behavior, as well as incoordination of mental activities. Most patients do not recognize their illness, are reluctant to seek medical attention, have no self-awareness, are generally conscious, and have basically normal intelligence, but some patients may develop cognitive impairment during the course of the disease. The course of the disease is generally prolonged, with recurrent episodes, exacerbation or deterioration, and some patients eventually experience decline and mental disability, but some patients can remain cured or basically cured after treatment. The clinical symptoms of schizophrenia are very complex and diverse, and the clinical manifestations can vary greatly among different types and stages of patients. However, it has characteristic thinking and perceptual disorders, emotional and behavioral incoordination and detachment from the real environment, which are now described separately as follows: (1) Thought association disorder: the thought association process lacks coherence and logic, and the disease has characteristic disorders. The characteristics of the patient in consciousness, thinking associations scattered or split, lack of specificity and realism. In conversation, the patient may give irrelevant answers to questions and give irrelevant descriptions of things, making it difficult for people to understand, which is called “lax thinking”. In severe cases, the speech is fragmented, that is, “broken thinking”, and even the lack of connection between individual statements, called “word jumble”. (2) Affective disorders: emotional retardation and indifference, incompatibility of emotional responses with the content of thought and external stimuli, are important features of schizophrenia. The earliest ones involve more delicate emotions, such as lack of concern and sympathy for comrades and lack of consideration for relatives. Later, the patient becomes emotionally unresponsive to things around him or her and less interested in life and learning. As the disease progresses, the patient’s emotions become increasingly indifferent, even to things that cause great pain, but also show a surprisingly flat, and finally the patient can lose any emotional connection with the surrounding environment. (3) Disorders of volitional activity: The patient’s activities decrease, lack of initiative, and behavior becomes withdrawn, passive, and retreating, i.e., the volitional activity is diminished. The patient’s demand for life, study and labor is reduced, manifested by not actively interacting with others, unexplained absenteeism from school or work, etc. In severe cases, the behavior is extremely passive, and so are the basic requirements of life. Patients do not pay attention to hygiene, do not bathe for a long time, do not comb their hair, live a lazy life, do nothing all day long, sit or lie in bed. Some patients’ behavior is completely incompatible with the environment, eating something inedible (such as soap, sewage), hurting their own bodies, etc., called intention inversion. Or dominated by hallucinations and bizarre thoughts. (4) Hallucinations and sensory perception syndrome; hallucinations are seen in more than half of the patients, and sometimes can be quite persistent. The most common are hallucinations, mainly of a verbal nature. They are divided into commentary hallucinations, command hallucinations, and thought chirps. Phantom smell, phantom touch, and phantom taste are less common. (5) Primary delusions: Primary delusions do not occur frequently in this disease, but they are diagnostically important and a characteristic symptom of this disease. These delusions occur suddenly and cannot be explained by the patient’s situation and psychological background at that time. For example, when a patient returns from abroad, he suddenly feels that his environment has changed as soon as he gets off the train, and he sees that the attitudes of people around him have changed, all of them are paying attention to him, pedestrians are looking at him in a special way, and the attitudes of his family members are different from usual, and the conversations are talking about things related to him, etc. Secondary delusions often occur on top of hallucinations. (6) Catatonic syndrome: The most obvious manifestation of this syndrome is catatonic rigidity, in which the patient is reticent, defiant, or in passive compliance, and is accompanied by increased muscle tone. Patients with schizophrenia generally have no impairment of consciousness, and delusions, hallucinations, and other thought disorders are usually found in a conscious state. In the early stages of the disease, there is no intellectual impairment, and the patient’s self-awareness is mostly lacking – the majority of patients do not admit that they have the disease and refuse to seek medical care and medication, which requires early detection by family members and timely transportation to a hospital or psychiatric specialist.