fMRI - availablity/utility
bill at nsma.arizona.edu
Mon Nov 1 00:28:19 EST 1993
goetz at acsu.buffalo.edu (Philip S. Goetz) writes:
>In article <CFGx04.F9E at umassd.edu>, rleary at UMASSD.EDU writes:
>|> Also - has physical evidence of brain damage attributable to drug abuse -
>|> cocaine, LSD, amphetamines, etc. - ever been demonstrated using imaging
>|> about a group of young people who literally blew their minds with some designer
>|> drug - and I believe there were pictures/images showing this type of damage
>|> in a real human brain.
I remember an article about 14 years ago showing brain tissue samples
from a normal rat or mouse, and one exposed to large amounts of marijuana
smoke. The latter showed lots of neuron death. But the dosage may have
been absurdly high, and you might get a similar effect with cigarette smoke.
I don't know what journal it was in; possibly Science.
There is at least one very well established example, a hallucinogenic
designer drug called MPTP that turned out to cause Parkinsonian
symptoms, such as tremor, slowness of movement, or even paralysis. It
causes these things by destroying neurons in a part of the brain
called the substantia nigra, which is the same part damaged in
Parkinson's disease. In fact, MPTP is now being used in an animal
model for Parkinson's disease.
To my knowledge there is no convincing evidence for brain damage
resulting from cocaine, amphetamine, LSD, marijuana, or heroin.
Cocaine, amphetamine, and heroin are known to lead to long-lasting
changes in the chemistry of the brain, but most likely the doses
necessary to kill brain cells would be lethal by other mechanisms,
such as heart arrest.
Of course there are many ways drug abuse could cause brain damage
indirectly. For example, an overdose of many drugs could cause
respiratory depression, reducing the oxygen flow to the brain and thus
killing neurons. Or, even more obviously, driving a car while stoned
could lead to severe head trauma.
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