The main cause of hallucinations before going to bed may be psychosomatic disorders, such as the problem of schizophrenia, which, as a serious mental illness, mainly causes hallucinations, and more commonly problems of hallucinations of hearing and vision. If the problem of hallucinations occurs frequently before going to bed, schizophrenia must be considered first. It is also possible to have problems with consciousness, especially problems with disorders of consciousness. Before going to bed, because of decreased clarity of consciousness and narrowed range of consciousness, it is possible to have abnormalities in sensation and perception, and even hallucinations may occur. Of course, serious physical diseases are also prone to hallucination problems before going to bed, such as encephalitis. These diseases may have a severe delirium state, with a large number of horrific hallucinations before sleep, such as seeing animals out of thin air, etc. These causes are more common.