Perfusion fMRI for Cognitive Neuroscience

University Of Pennsylvania, Philadelphia PA

Investigators

Abstract

Perfusion fMRI for Cognitive Neuroscience Abstract With National Science Foundation support, Dr. Detre and colleagues will conduct a three-year investigation aimed at developing perfusion functional magnetic resonance imaging (fMRI) for use in studies of cognitive brain function. The sensitivity of perfusion fMRI will be increased by adapting the methods to higher magnetic field strengths. Image quality will be improved by using imaging strategies that are not sensitive to degradation by variations in adjacent tissue types. In addition to optimizing image acquisition parameters, image analysis procedures will also be developed that are specifically optimized for perfusion fMRI. These acquisition and analysis methods will be disseminated to other scientists through publications, web-sites, and integration into currently available software packages. The larger goal of this project is to validate perfusion fMRI for use in cognitive brain mapping in experiments on face recognition and risk-taking. As is commonly known, MRI methods provide detailed pictures of brain anatomy. However, the methods can also be used to see how brain function changes with cognitive tasks such as learning, memory, language, and emotion. This is possible because blood flow increases in a brain region that is being used to perform a specific task. Most MRI methods used for mapping brain function only detect such regional blood flow changes indirectly. Over the past decade, Dr. Detre and others have been developing noninvasive perfusion MRI methods to directly measure cerebral blood flow. These methods can quantify blood flow both at rest and with cognitive tasks. Because the measurement is direct and quantitative, the results are more stable over space and time than with indirect and non-quantitative methods. They will be particularly useful for examining behavioral state changes, learning, and responses to pharmacological manipulation. Perfusion MRI can also measure changes in certain brain regions that are difficult to visualize with other methods due to the presence of adjacent tissues with differing effects in a magnetic field. It is anticipated that perfusion fMRI will contribute significantly to our understanding of cognitive brain function over the next decade.