Skill is a cellular insulation that wraps neural circuits and that grows in response to certain signals.

The sweet spot: that productive, uncomfortable terrain located just beyond our current abilities, where our reach exceeds our grasp. Deep practice is not simply about struggling it's about seeking a particular struggle, which involves a cycle of distinct actions.

Practice makes myelin, and myelin makes perfect.

Baby steps are the royal road to skill.

I discovered when I went all out, when I put 100 percent of my energy into some intense, impossible task - when my heart was jack-hammering, when lactic acid was sizzling through my muscles - that's when I felt good, normal, balanced.

To sum up: it's time to rewrite the maxim that practice makes perfect. The truth is, practice makes myelin, and myelin makes perfect.

Although talent feels and looks predestined, in fact we have a good deal of control over what skills we develop, and we have more potential than we might ever presume to guess.

There is no substitute for attentive repetition.