> > Basic Principles of Neuroimaging

This is the free portion of the full article. The full article is available to licensed users only.
How do I get access?

Basic Principles of Neuroimaging

Energy Requirements of Brain Tissue

The energy demand of the nervous tissue is very high and therefore sufficient blood supply to the brain must be maintained consistently. A normal adult male’s brain containing approx. 130 billion neurons (21.5 billion in the neocortex) (Pakkenberg and Gundersen 1997)comprises only 2 % of total body mass, yet consumes at rest approximately 20 % of the body’s total basal oxygen consumption supplied by 16 % of the cardiac blood output. The brain’s oxygen consumption is almost entirely for the oxidative metabolism of glucose, which in normal physiological conditions is the almost exclusive substrate for the brain’s energy metabolism (Clarke and Sokoloff 1999). It must be kept in mind that the glucose metabolized in neuronal cell bodies is mainly to support cellular vegetative and house-keeping functions, e.g. axonal transport, biosynthesis of nucleic acids, proteins, lipids, as well as other energy-consuming processes