Generally, the following three aspects can be compared and analyzed 1. Longitudinal comparison: compared with its past consistent performance, see whether the change of its mental state is obvious, whether there is a great change, if there is no obvious cause out of perception, thinking thoughts, speech behavior and the previous great change. If out of thin air he hears someone talking about him, cursing him, suspecting that others are talking about him; thinking that there are many people who want to harm him, spying, stalking, talking to himself, laughing to himself, or walking aimlessly, etc., he should see a doctor to see if there is a mental abnormality. 2. Horizontal comparison: that is, whether the difference is obvious when compared with the mental state of most normal people. If the difference is very large, such as a change in personality without a cause, there may also be a mental abnormality. Whether the duration of normal reactions exceeds the general limit, such as being praised by a supervisor, but he has been talking and laughing to himself for months. Another example is unexplained excitement, talk a lot or depressed mood, no spirit, less speech and less movement. 3, attention should be paid to the specific analysis and judgment in conjunction with the psychological background of the person concerned and the situation at the time. For example, when no one is around, he can hear someone talking about him, or a voice ordering him, nothing happens, indeed every day happy and smiling, or sullen, etc. Also observe the frequency, duration and severity of the mental abnormality. For example, six months or years after the loss of love are sad and do not go out, etc.. The above performance should be early to the psychiatric hospital to reduce delays, early detection, early treatment, the prognosis will be better.