“If you really want to focus on something, says Castellanos, the optimum amount of time to spend on it is ninety minutes. "Then change tasks. And watch out for interruptions once you're really concentrating, because it will take you twenty minutes to recover.”

“Recently, the search for what he calls "the splinters that make up different attention problems" has taken Castellanos in a new direction. First, he explains that your brain is far less concerned with your brilliant ideas or searing emotions than with its own internal "gyroscopic busyness," which consumes 65 percent of its total energy. Every fifty seconds, its activity fluctuates, causing what he calls a "brownout." No one knows the purpose of these neurological events, but Castellanos has a thesis: the clockwork pulses enable the brain's circuits to stay "logged on" and available to communicate with one another, even when they're not being used. "Imagine you're a cabdriver on your day off," Castellanos says. "You don't need to use your workday circuits on a Sunday, but to keep those channels open, your brain sends a ping through them every minute or so. The fluctuations are the brain's investment in maintaining its circuits online.”

“Once out of your cradle, you don't focus on the world in the abstract, perceiving things for the first time, but in synchrony with your accumulated knowledge, which enriches and helps define your experience, as well as ensuring its uniqueness.”

“In a variation on James's recipe for interesting experience--the familiar leavened by the novel--Hobbs's "art of choosing difficulties" requires selecting projects that are "just manageable." If an activity is too easy, you lose focus and get bored. If it's too hard, you become anxious, overwhelmed, and unable to concentrate. Tellingly, one group is distinguished by its zeal for the kind of work that requires you to give it all you've got: high achievers particularly relish taking on risky projects that have only a 50/50 chance of success.”

“Because you actually might not know what activities truly engage your attention and satisfy you, he says, it can be helpful to keep a diary of what you do all day and how you feel while doing it. Then, try to do more of what's rewarding, even if it takes an effort, and less of what isn't. Where optimal experience is concerned, he says, "'I just don't have the time' often means 'I just don't have the self-discipline.”

“Temperamentally anxious people can have a hard time staying motivated, period, because their intense focus on their worries distracts them from their goals.”

“Arguably the mos intriguing characteristic assessed by the Multidimensional Personality Questionnaire (MPQ), a widely used test developed by the University of Minnesota's eminent psychologist Auke Tellegen, is "absorption," which describes a particular style of focusing. If you get a high score in this trait, you're naturally inclined toward what he calls a "respondent" or "experiential" way of focusing.”