Worth doing a google search on the term, see what you come up with, much of it refers to narcolepsy but hypnagogic hallucinations aren't necessarily connected to narcolepsy, they can occur on their own also.

Turned out to be very useful for me also to poke round for more info on this, I discovered something else about sleep that I had no clue that anyone else experiences, they call it, of all things, "exploding head syndrome". Had never heard of this before, but I have it, info at: http://www.freep.com/news/health/good24_20001024.htm

It's entirely benign yet can be quite frightening, now that I know what it is, great help.

Now that we've tackled hypnagogic hallucinations and exploding head syndromes, we should be able to hang out a shingle and set up shop as sleep experts! *Grin* Maybe people can pay us to tuck them in with cozy beds and blankies, while we snooze elsewhere.

Sarah