Froma NYTImes article

"The Rise of the New Groupthink"

Research strongly suggests that people are more creative when they enjoy privacy and freedom from interruption. And the most spectacularly creative people in many fields are often introverted, according to studies by the psychologists Mihaly Csikszentmihalyi and Gregory Feist. They’re extroverted enough to exchange and advance ideas, but see themselves as independent and individualistic. They’re not joiners by nature.

and

Solitude has long been associated with creativity and transcendence. “Without great solitude, no serious work is possible,” Picasso said. A central narrative of many religions is the seeker — Moses, Jesus, Buddha — who goes off by himself and brings profound insights back to the community.

and quoting Steve Wozniak:

Mr. Wozniak offers this guidance to aspiring inventors:

“Most inventors and engineers I’ve met are like me ... they live in their heads. They’re almost like artists. In fact, the very best of them are artists. And artists work best alone .... I’m going to give you some advice that might be hard to take. That advice is: Work alone... Not on a committee. Not on a team.”

...

But decades of research show that individuals almost always perform better than groups in both quality and quantity, and group performance gets worse as group size increases. The “evidence from science suggests that business people must be insane to use brainstorming groups,” wrote the organizational psychologist Adrian Furnham. “If you have talented and motivated people, they should be encouraged to work alone when creativity or efficiency is the highest priority.”