ABSTRACT
Brain plasticity or cortical reorganization can be defined as follows: when a pathological process affects the function of one part of the brain, another part of the brain attempts to take over that function and succeeds at least partially. Imaging is essential in revealing brain plasticity because of its ability to show changes in brain function over time. A number of different techniques have shown brain plasticity in both animals and humans. These include experimental techniques, such as stem cell tracking, most of which lie outside everyday clinical practice. The chapter focuses on a technique which is readily available, namely blood oxygen level-dependent (BOLD) functional magnetic resonance imaging (fMRI). In interpreting BOLD fMRI studies, it is imperative to keep in mind that the BOLD signal is a measure of a vascular response rather than a measure of neuronal activity. The effect of abnormal vasculature on the BOLD signal has also been reported in other pathologies such as arteriovenous malformations.
