Prologue

Currently, all life science uses 3-D imaging. In particular, imaging of brain function at the macroscopic and microscopic scales has developed rapidly. Out of all the various biological elements of the brain, the cerebral blood flow is the most indispensable in supplying oxygen and nutrition. Nevertheless, the cerebral blood flow fluctuates temporally and spatially in tune with brain activity. The biological mechanisms underlying this fluctuation have not yet been clarified. This chapter introduces the author’s motivation for writing this monograph.