Figure 5From: Physiological basis and image processing in functional magnetic resonance imaging: Neuronal and motor activity in brainAn example of an fMRI image of the normal brain is shown. The numbers indicate the relative intensity of cerebral cortex at various sites relative to CSF which assigned a value of 100 (written in red). The substantial variation in the intensity of cortex is primarily due to the 'partial volume' phenomenon.Back to article page