Dissociative trance state and attachment state: The trance state is manifested by an obvious reduction in the range of consciousness, the person is in a self-contained state, his or her attention and conscious activity is limited to one or two aspects of the current environment, and only responds to individual stimuli in the environment. Differential diagnosis of dissociative trance state and possessive state: 1. Dissociative amnesia: It belongs to psychogenic amnesia, in which the patient has no organic damage such as head or brain trauma, but suddenly loses memory of significant events he/she experienced; the forgotten events are often related to trauma or stressful events, not due to accidental reasons for not being able to think of them. If it is limited to events that occurred within a certain period of time and cannot be recalled, it is called limited or selective amnesia; those who lose memory of all their past lives are called extensive amnesia. 2.Dissociative wandering disorder: It is a special form of dissociative disorder. Patients often develop under the effect of acute mental stimulation, suddenly wandering from a certain place to another area, often mostly from a disagreeable residence, and may leave home or workplace to travel to a foreign place; the travel place may be a familiar and emotionally meaningful place in the past. At this time, although the patient is in an awakened state, but the scope of consciousness is reduced, the wandering lacks planning and purpose, but the ability to live a basic daily life (such as eating and living) and simple social contacts (such as buying tickets, taking a bus, asking for directions, etc.) are still maintained; some patients forget their past experiences and appear as a new identity, others do not see any obvious abnormalities in their words, actions and appearance; lasting from a few minutes to a few days or longer The behavior during this period is quite complete, and afterwards it is completely forgotten or only partially recalled. The typical delirium is extremely rare. 3. Dissociative lucidity: after trauma or triggered by traumatic experience, deeper disturbance of consciousness occurs, maintaining a fixed posture for a long time, lying or sitting on the back, no speech or random movements, and no response to light, sound and pain stimuli. The patient’s muscle tone, posture, and breathing may not be significantly abnormal at this time. When the upper eyelids are opened by hand, the eyes can be seen to turn downward, or the eyes can be tightly closed; this indicates that the patient is neither asleep nor in a comatose state. Generally, the patient can wake up on his own in a few minutes.