Visualizing and measuring brain activity.

Neuroimaging techniques, such as PET, enable scientists to visualize and measure brain activity. Specifically, this type of scan reveals which brain areas are being used for different cognitive tasks. When the various images are pieced together, one can see the pathways for information processing. For example, if someone is processing a visual image while in a PET scanner, a scientist can see the flow of the information sent to the primary visual cortex, and then he or she can view the general pathways as the image is identified and as it moves on to higher-order processing.
Answer the following questions:

• How does PET scan work? State how they are different from MRI and functional magnetic resonance imaging (fMRI). Why is radioactively labeled glucose often used as a metabolic tracer? What does it mean if glucose is being absorbed or used in one area more than another?
• What are neural networks, and how do neural networks relate to localized and global brain functioning? What does our knowledge of neural networks tell us about how the brain processes information? How do PET scans and fMRI allow us to see the flow of information throughout networks?
• Do people only use a small percentage of their brain? Use what you know about neural networks and functional imaging scans to address this belief. Do you believe that we only use 10 percent of our brain capacity? Would someone be able to demonstrate via various cognitive tasks that no part of the brain sits in the cranium unused?

Respond to at least two of your classmates

To support your work, make sure to utilize your course and text readings. When asked, also utilize outside sources. As in all assignments, make sure to cite your sources in your work and provide references for those citations utilizing APA format.