Posted by SLS on August 20, 2004, at 7:40:47
In reply to Any ideas what these MRI Scans are showing up?, posted by denise1904 on August 19, 2004, at 14:06:13
fMRI determines brain activity by measuring blood flow to specific regions or structures. Changes in brain activity/blood flow can be mapped during the performance of mental tasks, induction of physical sensations, and introduction of drugs, among other things.
There are other types of imaging that can resolve brain function in different ways.
SPECT scans (Single Photon Emission Computed Tomography) can generate three-dimensional renderings similar to X-ray CAT scans. Like the fMRI, it measures blood flow (perfusion).
PET scans (Positron Emission Tomography) use radioactive labelled glucose to see where in the brain it is being used. This is another measure of activity that is more direct. I believe that other radio-labelled compounds like drugs can be used also.
I don't know what has become of it, but there was a technique used that superimposed a PET scan on top of a MRI to give better resolution of the structures involved in brain activity.
- Scott
poster:SLS
thread:379494
URL: http://www.dr-bob.org/babble/20040817/msgs/379823.html