Ericsson called this process “deliberate practice” and defined it as working on technique, seeking constant critical feedback, and focusing ruthlessly on shoring up weaknesses. (For practical purposes, we can consider “deliberate practice” and “deep practice” to be basically the same thing—though since he's a psychologist, Ericsson's term refers to the mental state, not to myelin. For the record, he is attracted to the idea. “I find the correlation [between myelin and skill] very interesting,” he told me.)
