Why do our eureka moments arise from quiet contemplation and even sleep?
Research suggests focus allows the brain to cast a broader net and recruit more neurons for the problem at hand. In physics and brain research this is known as phase shifting. For brain purposes, think of phase shifting as the period of time when neurons are released from one task and available for the next. A slightly longer phase shift allows the brain to recruit more available neurons for a new task, dramatically increasing processing power.
Research shows that people who have longer phase shifts demonstrate higher IQs. The effects are both subtle and powerful. A 1 millisecond increase in phase shifting can result in a 20 point increase in IQ.
I'm not aware of research (yet) that directly measures an individual's ability to lengthen phase shifting through mind focusing techniques. But there's a lot of indirect evidence demonstrating that the brain is operating differently and more creatively in a position of calm-- suggesting you can amplify your intellectual effectiveness through focus.
Research seems to be slowly but surely verifying what the ancients have known.