Sleeper issues.

I have experienced sleep paralysis in almost all of its forms, from terrors to vibrations and auditory hallucinations to out-of-body experiences ("Night of the Crusher," SN: 7/9/05, p. 27). Most often it is completely terrifying, but I did have one episode that was elating.

Sweet dreams.

KATHLEEN MILROY, ONTARIO, CANADA

The manifestations reported by sufferers of sleep paralysis are eerily similar to the visitation of death in "The Snows of Kilimanjaro," written by Ernest Hemingway and first published in Esquire in 1936:

   It moved up closer to him still and
   now he could not speak to it, and
   when it saw he could not speak it came
   a little closer, and now he tried to send
   it away without speaking, but it moved
   in on him so its weight was all upon
   his chest, and while it crouched there
   and he could not move, or speak, he
   heard the woman say, "Bwana is
   asleep now. Take the cot up very gently
   and carry it into the tent."

   He could not speak to tell her to
   make it go away and it crouched now,
   heavier, so he could not breathe. And
   then, while they lifted the cot, suddenly
   it was all right and the weight
   went from his chest.

History doesn't tell us if sleep paralysis was Papa's inspiration, but no better description could be offered.

ROBERT PERRY FISHER, RALEIGH, N.C.

Might this same phenomenon also explain the common childhood fear of "monsters under the bed"? I don't know how common this is across cultures, but it would be interesting to look.

ROLF TAYLOR, CLEVELAND HEIGHTS, OHIO

If the condition is so severe as to paralyze the lungs and cause asphyxiation, has any study reported deaths due to sleep paralysis?

VYTAS MISIULIS, CHICAGO, ILL.

I didn't run across any reports of deaths due to sleep paralysis.--B. BOWER