In an interesting article in the journal General Hospital Psychiatry, researchers compared the experiences of hallucinations from sufferers of both Narcolepsy and Schizophrenia. There were some particularly interesting bits of information that can be found within the piece.
For example, when the subjects were asked if they had ever experienced any hallucinations in their lives, the Narcolepsy suffers reported 10% higher incident rate than the Schizophrenia group. Also, 65% of the members in the Narcolepsy category reported having hypnagogic hallucinations, (hallucinations occurring at the onset of sleep), while only 4% of the Schizophrenia sufferers reported such events.
Auditory hallucinations within the Narcoleptic group usually consisted of generalized “sounds”. Schizophrenics on the other hand tended to experience auditory hallucinations that had a distinct voice or voices that would have, “third-person qualities ”.
For those who have had out-of-body lucid dreaming experiences, this next quote may hold some interest for you. In regards to some of the hypnagogic hallucinations that the narcoleptics faced, “during the hallucination, typically a combination was present of the actual environment of the patient (such as the bedroom) superimposed with the hallucinated perceptions, for example, a family member entering the room, while not actually being in the house”. It was certainly interesting material to say the least.
Droogleever, H. A., Lappenschaar, G. A., Nienhuis, F. J., Furer, J. W., Hodiamont, P. P., Rijnders, C. A., et al. (n.d.). Psychotic symptoms in narcolepsy: phenomenology and a comparison with schizophrenia. General Hospital Psychiatry. Available online 24 January 2009, ISSN 0163-8343