NSF Award
9022190
The architecture of the cerebral cortex of the brain shows sophisticated connections among and between the layers of nerve cells, and within and between functional units called columns. Nerve cells have very high metabolic rates, and blood flow to different areas of the brain depends on which parts are most active at particular times. Blood flow is altered by regional changes in oxygen and carbon dioxide content, as well as by blood pressure. It is known that vascular capillary networks show flow changes with regional, cyclic activity of opening and closing. The opening of a capillary network to a local region is called recruitment, and provides local cycling of nutrients (such as oxygen) and waste metabolites to active biological tissues. This work uses a unique approach to combine the concepts of temporal cycling, capillary recruitment, columnar organization of the cortex, and vascular architecture of the cortex. There are suggestions that the recruitment cycles here are relatively quite rapid. Measurements with novel technology will allow new results at a very fine level in time and space, to determine how vascular units composed of groups of capillaries regulate flow in response to demand. The impact of this novel work will be high not only on the obvious clinical issues, but on the many areas of neuroscience that deal with functional architecture and activity patterns in the brain.
