Marcus E. Raichle
Election Year: 1996
Primary Section: 28, Systems Neuroscience
Membership Type: Member
My research centers on the use of two brain imaging techniques, positron emission tomography or PET and magnetic resonance imaging or MRI. Both techniques permit an assessment of the function of the human brain because they are able to detect changes in blood flow or metabolism that are the consequence of changes, locally, in the activity of neurons and their supporting cells. In addition, MRI provides excellent anatomical data on the living human brain. I have been involved with all aspects of the development of these techniques for the study of brain function since their introduction in the early 1970's. My most recent research has been focused on the development of a better understanding of how the normal human brain implements language, memory and emotion. Parallel work in my laboratory has concerned the relationship between brain blood flow, brain metabolism and neuronal activity. Conventional wisdom had suggested that the brain fueled its work by burning glucose to carbon dioxide and water. Evidence uncovered in our laboratory demonstrated that when the brain increases its work transiently to accommodate such things as language, memory, and emotion it does so without the use of additional oxygen. Energy is extracted from glucose by metabolizing it only as far as lactate. Because blood flow responds to this increase in glucose use there appears within the brain local areas of increased oxygen content (i.e., supply exceed demand). We are working to understand how and why the brain does this.