Michael Merzenich talks about re-wiring the brain. In a nutshell: much of the brain's ability to process information is causally related to correct processing of language sounds. During the "critical period" of infant brain development, inherited flaws or bad inputs may distort language sound processing, leading to general low performance on cognitive tasks. Specialized training taking about 30 hours can rectify the problem. The same training is effective at protecting the cognitive abilities of aging brains.