Although initially controversial, the idea that the mammalian brain is 'plastic' and adaptive is now a dominant theme in neuroscience. The plasticity of connections between nerve cells is thought to underlie many different types of learning and memory, as well as sensory development. The changes in organisation can be remarkably rapid, even in adults. Blakemore has shown that the visual parts of the human cortex become responsive to input from the other senses, especially touch, in people who have been blind since shortly after birth. After stroke or other forms of brain injury, reorganisation of this sort can help the process of recovery, as other parts of the brain take over the function of the damaged part.