In article <2a97qa$lq7 at usenet.INS.CWRU.Edu>, ery2 at po.CWRU.Edu (Edwin R. Yeh) writes:
|>|> In a previous article, cs60a-ae at po.EECS.Berkeley.EDU (Class Account) says:
|>|> > My name is Seth Piezas and I have been active in lucid dreaming
|> ...
|> > I think I have got some sort of solution, however. A little
|> >while ago I read about fast MRI and the ability to localize responses
|> >to sayign certain words and thinking certain thoughts.
|>|> What you are referring to is the PET (Positron Emission Tomography)
|> scan. By superimposing PET scan with MRI, one can better see which
|> region of the brain is responsible for a certain activity. I believe
|> MRI cannot detect any activities since it simply detects the concentration
|> of hydrogen ions.
There has been a recent (well actually it was developed about 10 yrs. ago)
development in MRI which allows one to measure "blood flow" and therefore
functional activity on a relatively small time scale (1-10 sec) and with the
resolution close to a structural MR. For some specific examples see:
Kwong et al, (1992), "Dynamic Functional Magnetic Resonance Imaging of Human
Brain Activity During Primary Visual Stimulation", Proc. Natl. Acad. Sci. USA,
89, 5675.
Turner et al, (1993) "Functioanl Mapping of the Human Visual Cortex at 4 and
1.5 Tesla Using Deoxygenation Contrast EPI" Magnetic Resonance in Medicine,
29, 277.
The technology is still relatively young so it is unclear what can and
cannot be detected using functional MRI (fMRI), but stay tuned, the field is
moving fast.
Randy