Susan Cain:

The advice sounds unconventional, but scientists are beginning to recognize that solitude is a catalyst for expert performance.  When you're alone, explains K. Anders Ericsson, PhD, a research psychologist who studies excellence, you can make headway on the tasks that are most challenging to you personally.  "If you want to improve what you're doing," Ericsson told me, "you have to be the one who generates the move.  But in a group, you're the one generating the move only a small percentage of the time."

"Secrets of a super successful introvert"