When the patient is unconscious and there is no external interference, the thought process is suddenly interrupted. The patient suddenly stops talking and then resumes speaking a few moments later, but the content of the speech is not the original topic. Clinical attention should be paid to the differential diagnosis with other symptoms. 1, thinking runaway: manifested as an increase in the amount of thinking activity and rapid shift. 2, slow thinking: this is a kind of inhibitory thinking association disorder. 3, thinking poor: this kind of symptoms in appearance and thinking slow similar, but there are essential differences. The main characteristics are: the content of the mind is empty, poor concepts and vocabulary, often no clear response to general inquiries, or simply answer “do not understand”, “nothing”, and usually do not actively talk. Patients feel that their minds are empty and have nothing to think or say. But the patient is indifferent to this. Most often seen in schizophrenia or organic brain dementia state. 4.Thoughts break down: The patient’s thought association process breaks down in a clear consciousness, lacking the inner sense of coherence and proper logic. 5. Scattered thinking: The patient’s thinking activity may be characterized by loose associations, scattered content, a lack of pertinence and relevance to the problem, and a lack of certain logical relationships, giving the impression that it is difficult to converse, and that the subject and intent of his or her words are not easily understood. This is an early symptom of schizophrenia. 6.Thinking incoherence: superficially similar to thinking breakdown, but it arises in the case of severe impairment of consciousness. 7.Pathological redundancy: When the patient is narrating things, he or she goes to great lengths to give unnecessary, detailed and cumbersome descriptions of individual details, so that some meaningless and cumbersome sections obscure the main content of the problem.