Measuring Blood Flow in the Brain

OBJECTIVE: a) to explore the usefulness of Near Infrared Spectroscopy (NIRS) as a means of mapping brain activity, to see whether the results are similar to those of fMRI and b) to see whether spontaneous brain blood flow changes coincide with changes in behavior. STUDY POPULATION: 50 healthy volunteers. DESIGN: The study will look for correlations between NIRS and fMRI signal changes in the same subjects. It will also detect relationships between spontaneous blood flow shifts and shifts and changes in cognitive performance. Finally, NIRS will be combined with a frontal lobe activation task to see if blood flow changes can be detected over the hairless skin of the forehead in a simple, standardized manner that might yield a diagnostic test for frontal injury. OUTCOME MEASURES: Graded changes in blood flow and oxygen, measured with NIRS and fMRI and variations in response time on a word task.

- INCLUSION CRITERIA: Age 18 to 60, inclusive. EXCLUSION CRITERIA: - Pregnancy. - History of hypertension. - History of any disease of the central nervous system. - Current use of sedating medication, including antihistamines. - Subjects with any of the following will be excluded from MRI testing: aneurysm clip; implanted neural stimulator; implanted cardiac pacemaker or auto-defibrillator; cochlear implant; ocular foreign body, such as metal shavings; permanent eyeliner; insulin pump; or irremovable body piercing due to the possible dangerous effects of the MRI magnet upon metal objects in the body.

Study Location
Maryland