Research and studies conducted by:
Dr. Nolan Altman and Dr. Byron Bernal of the Radiology Department
Functional Magnetic Resonance Imaging is a new procedure that shows us how the brain works.
Up to now we have had the computed-tomography-scan and magnetic resonance exams (Do the acronyms CT-Scan and MRI look more familiar to you?) to see the brain anatomy. These exams produce images that show the surface and the inner parts of the brain as in the best pictures of a scholarly book. But the function of the brain could not be assessed with these tools. For this purpose we used to deal with electro-encephalograms, also named EEG, and more sophisticated procedures like evoked potentials, a sort of electrical detection of the activity of the cortex. And these exams are not images of the brain. Instead they are a representation of groups of waves produced by the electrical activity of the cortex averaged at a given point. The bigger the wave (or the higher its frequency) the more the activity.
Functional magnetic resonance imaging (fMRI) allows us to see the brain function related to its anatomy. This is depicted as a map of colors, like the weather map on the TV-news.
The red area shows strong activation of cortex working in language comprehension. The anterior yellow and green areas are zones that are less active.
MRI. Horizontal cut of the head done a little bit over the level of the ears. Do you recognize the eyes here? They are located in the superior aspect of the image. Both hemispheres are divided by the middle line. The left hemisphere appears at the right of the image. The white matter is... White, yes. The cortex is gray.
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