As the brain matures, one thing that happens is the pruning of the synapses. Synaptic pruning does not occur willy-nilly; it depends largely on how any one brain pathway is used. By cutting off unused pathways, the brain eventually settles into a structure that’s most efficient for the owner of that brain, creating well-worn grooves for the pathways that person uses most. Synaptic pruning intensifies after rapid brain-cell proliferation during childhood and again in the period that encompasses adolescence and the 20s. It is the mechanism of “use it or lose it”: the brains we have are shaped largely in response to the demands made of them.


|http://nyti.ms/bQzj8l