Hi all: Why isn't there a similar effect when people undergo MRIs? I read somewhere the units generate a magnetic field 30,000 times stronger than the earth's magnetic field. What am I missing?
Jean Edwards [EMAIL PROTECTED] (home for summer, yeahhhhhhhhhhhhh) ----- Original Message ----- From: "Stephen Black" <[EMAIL PROTECTED]> To: "Teaching in the Psychological Sciences" <[EMAIL PROTECTED]> Sent: Friday, June 27, 2003 3:41 PM Subject: Transcranial magnetic stimulation (TMS) (was; Betty Edwards) > On 27 Jun 2003, Paul C. Smith wrote: > > > Not an answer, but a related piece... In last Sunday's NYTimes > > Magazine > > there is a little article about a guy who claims to be able to make > > people creative, temporarily, using magnets to turn off conceptual > > parts of the brain. > > > > http://www.nytimes.com/2003/06/22/magazine/22SAVANT.html > > > > Thanks for the url to that interesting article, Paul. The description > about "using magnets", although accurate, might suggest that this is > some kind of quack apparatus. In fact, it's for real. > > What the magnetism does is induce an electric current to flow across > the cortex, so it's really a way to electrically stimulate the brain > without the need for surgery to implant electrodes. Alternatively, > you could skip the magnetic induction and just apply an electric > current to the scalp. But this is painful, while using magnetism is > not. The induced current seems mostly to disrupt brain functioning (a > kind of reversible lesion) but it still produces interesting effects, > some of which may turn out to be clinically significant. In Canada, > for example, TMS is approved for use as a treatment for depression. > But mostly, it's a new toy for neuroscientists to play with, if > they're lucky enough to have one. > > I think we discussed this some time ago. I recall I mentioned one of > the more intriguing experiments using TMS, one which apparently > showed that free will was an illusion. They shifted a subject's > finger choice in making a response by turning on TMS. The subject, > unaware of the stimulation, incorrectly thought he was making his own > decisions. It's: > > Brasil-Neto, J. et al (1992). Focal transcranial magnetic stimulation > and response bias in a forced-choice task. Journal of Neurology, > Neurosurgery, and Psychiatry. 55, 964-6. > > > Stephen > ______________________________________________________________ > Stephen L. Black, Ph.D. tel: (819) 822-9600 ext 2470 > Department of Psychology fax: (819) 822-9661 > Bishop's University e-mail: [EMAIL PROTECTED] > Lennoxville, QC J1M 1Z7 > Canada > > Dept web page at http://www.ubishops.ca/ccc/div/soc/psy > TIPS discussion list for psychology teachers at > http://www.frostburg.edu/dept/psyc/southerly/tips > _________________________________________________________ > > > --- > You are currently subscribed to tips as: [EMAIL PROTECTED] > To unsubscribe send a blank email to [EMAIL PROTECTED] > --- You are currently subscribed to tips as: [EMAIL PROTECTED] To unsubscribe send a blank email to [EMAIL PROTECTED]
