Carl%20Sagan%20-%20The%20Demon%20Haunted%20World

Hallucinations
maybe longer, you're immobile and acutely anxious. You feel a
weight on your chest as if some being is sitting or lying there. Your
heartbeat is quick, your breathing laboured. You may experience
auditory or visual hallucinations of people, demons, ghosts,
animals or birds. In the right setting, the experience can have 'the
full force and impact of reality', according to Robert Baker, a
psychologist at the University of Kentucky. Sometimes there's a
marked sexual component to the hallucination. Baker argues that
these common sleep disturbances are behind many if not most of
the alien abduction accounts. (He and others suggest that there
are other classes of abduction claims as well, made by fantasyprone
individuals, say, or hoaxers.)
Similarly, the Harvard Mental Health Letter (September 1994)
comments,
Sleep paralysis may last for several minutes, and is sometimes
accompanied by vivid dreamlike hallucinations that give rise
to stories about visitations from gods, spirits, and extraterrestrial
creatures.
We know from early work of the Canadian neurophysiologist
Wilder Penfield that electrical stimulation of certain regions of
the brain elicits full-blown hallucinations. People with temporal
lobe epilepsy - involving a cascade of naturally generated
electrical impulses in the part of the brain beneath the forehead
- experience a range of hallucinations almost indistinguishable
from reality: including the presence of one or more strange
beings, anxiety, floating through the air, sexual experiences,
and a sense of missing time. There is also what feels like
profound insight into the deepest questions and a need to
spread the word. A continuum of spontaneous temporal lobe
stimulation seems to stretch from people with serious epilepsy
to the most average among us. In at least one case reported by
another Canadian neuroscientist, Michael Persinger, administration
of the antiepileptic drug, carbamazepine, eliminated a
woman's recurring sense of experiencing the standard alien
abduction scenario. So such hallucinations, generated spontaneously,
or with chemical or experiential assists, may play a
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