Naked Science Forum
Life Sciences => Physiology & Medicine => Topic started by: Heather on 06/09/2008 15:42:59
-
Heather asked the Naked Scientists:
I recently discovered your podcast (http://www.thenakedscientists.com/HTML/podcasts/) and am trying to catch up and listen to all
of the previous downloads!
In a recent show you talked about why our eyes dilate in the dark. Does
the explication that it has to do with a chemical process also apply to why
people who take hallucinogenic drugs have dilated pupils?
What do you think?
-
"Street" drugs can cause large dilated pupils and tiny constricted "pinpoint" pupils...
Signs of [opiate] intoxication are decreased respiratory rate and pinpoint pupils.
http://www.emedicine.com/EMERG/topic20.htm
-
The drugs mimic or block the chemicals that the body uses as messengers to tell the eye's muscles to contract or relax.
There's more about those messengers here
http://en.wikipedia.org/wiki/Neurotransmitters