Far from being hard-wired and static, the brain is capable of dramatic reorganization. As one learns new skills or acquire novel experiences, the brain cells alter the way in which they respond to the outside world to reflect the changing circumstances and gained experience. These changes in our behaviour and brain functions are often accompanied by structural alterations in the brain circuitry. In studies on animal brains, it has been possible to visualize very localized structural changes, such as increased branching of the dendritic trees at the ends of axons. This would allow new synapses...