Romansh: Over hyped junk? possibly. > But unfortunately this does not help your argument one iota David. > > That we can get a crude image of vision from a very poor proxy for what our brain actually does. The observation that blood flow gives us information does not somehow diminish because it is measured in the degree of oxygenation in our blood.-I need to correct your imporession of what FMRI does. It shows intensity of blood flow to a region of the brain, not the oxygenation level of the blood. In a direct sense what you may mean in the level of oxygen demand by a region of the brain.