On Tue, 1 Apr 1997, CDW wrote:
> I'm a university student who has had an interest in biochemical
> psychology since taking a class about a year ago.
>> Recently I saw an article in the newspaper in which it was reported that
> studies had proven a connection between heavy smoking (nicotine intake)
> and a lessening of the severity and frequency of schizophrenic episodes.
> The article vaguely mentioned the neurochemical basis of this, but was
> very brief and unclear. Can anyone here please explain the chemical
> action in the brain by which nicotine "soothes" psychotic behaviors?
>> If this question, or this type of question, is inappropriate to this
> newsgroup, then I beg your forgiveness. Otherwise, I would very much
> appreciate any answer.
Seems quite appropriate to me. The interest in nicotine and schizophrenia
is very new, and I have a short summary of some research on the topic from
Nature, February 3, 1997 under the heading "New Schizophrenia Gene". The
report references a 1997 paper by Freedman in Proceedings of the National
Academy of Sciences, 94, 587-92.
The group has found a defect in the gene for a nicotinic cholinergic
receptor on chromosome 15. According to the report "These receptors act
as the brain's informational filters, helping it to separate important
stimuli from useless noise". The defective gene impairs these filters.
The tie-in to smoking is that "nicotinic receptors are normally activated
by...acetylcholine but can also be activated by nicotine from tobacco. The
researchers suggested that cigarettes might dampen the noise-filtering
problems".
Interestingly enough, I have an e-mail post from Dr. Salvatore Cullari
(Psychology Department, Lebanon Valley College), who says that he once
was involved in a survey which found that 75% of schizophrenics at a
large state hospital smoked as opposed to 50% of other patients, and that
"many of the schizophrenic patients reported that their auditory
hallucinations were temporarily blocked or reduced while smoking".
This sound like effective self-medication. Unfortunately, he says they
never followed up on their observations.
-Stephen
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Stephen Black, Ph.D. tel: (819) 822-9600 ext 2470
Department of Psychology fax: (819) 822-9661
Bishop's University e-mail: sblack at ubishops.ca
Lennoxville, Quebec
J1M 1Z7
Canada
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