Functional mapping in Alzheimer's disease using functional MRI and optical topography

Abstract

We examined brain function and hemodynamic change using functional MRI (fMRI) and optical topography and compared those differences between normal volunteers and patients with Alzheimer's. As activating tasks, simple finger tapping and word chain games (shiritori in Japanese) were conducted by both normal volunteers and patients with Alzheimer's. The activated area of normal volunteers depicted by fMRI was shown in the primary motor area (finger tapping) and Broca's area (word chain game) and the hemodynamic change measured by optical topography were mainly prominent in those two areas even though the spatial resolution of optical topography was low. In patients with Alzheimer's, the activation by fMRI was spread to the bilateral hemisphere of the cerebrum, the hemodynamic change by optical topography was also larger than that of normal volunteers. We considered that the hemodynamic response would be changed in patients with Alzheimer's, and both fMRI and optical topography might be useful to evaluate the difference of brain function in clinical cases.