Some individuals with narcolepsy may experience hallucinations that may occur at the beginning or at the end of a sleep period. These are often vivid and frightening. Examples of hallucinations may include hearing a phone ring or a person walking nearby, seeing people or animals that aren’t there, or having an out of body experience. When the hallucinations occur upon awakening, they are called hypnopompic hallucinations; when they occur when falling asleep, they are called hypnagogic hallucinations. Hallucinations often occur in conjunction with sleep paralysis.
https://rarediseases.org/rare-diseases/narcolepsy/