From: <mcintosh at bullwinkle.nia.nih.gov>
Date: 22 Oct 93 21:35:20 GMT
Sender: (AMDS Postmaster) <postman at alw.nih.gov>
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:
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
It is really a young strategy. So far it seems to be able to detect
only primary sensory input and primary motor functions. And the principle
how it is detect has not been completely established(deoxygenation is
told to be the reason, but CBV or CBF are also applicants. Personally,
I think all of them are involved, but CBV or CBF may be significant).
But there is no radiation problem as PET has, so activation study can
be repeated almost infinitely(in this case, habituation will become
the problem). And temporal and spatial resolution is excellent.
So fMRI may become the most powerful method in not so far a future.
However, you cannot sleep and dream in that noisy machine.....:-)
Tetsuji Rai tetsuji at rai.juice.or.jptrai at tanuki.twics.co.jp
Department of Radiology, Hospital attached to Univ of Tokyo
5-12-21, Toyotamakita, Nerimaku, Tokyo 176, Japan
voice: +81-3-3557-3936 fax: +81-3-3993-0323