ABSTRACT
Our ability to think, act, and feel depends on our brains being wired up in the right way at the right time. Wiring up a brain is likely to be a fairly tricky business. There are millions of cells involved, with the capacity to make billions of synaptic connections. Imagine the problems of getting the right cells into the right place and ensuring that they then make the right connections. Anyone who has owned a complex electronic device like a computer will also be aware that, in addition to being complicated to put together in the first place, it is also likely to go wrong, especially if maltreated. On the other hand, our brains go on working well for decades without appreciable deterioration of function, and will often work remarkably well even when damaged. How do our brains get wired up properly in the first place and how do they stay that way? Many people now believe that the answer lies in the inherent plasticity, or modifiability, of the brain. During development the brain adjusts its connections in the light of the environment in which it is operating. Throughout life cells seem to be able to modify themselves to compensate for losses of inputs or outputs. This chapter is about this remarkable flexibility in the organization of the brain that underpins all of our other behavioural capacities.
