Anders Ericcson is a psychology professor at Florida State University who has become the authority on the subject of expertise. His research attracted wide attention in 2008, when Malcolm Gladwells book "Outliers" popularized the 10,000-hour rule, which held that any discipline from playing the piano to jiu jitsu takes 10,000 hours to master.

In his forthcoming book, Ericcson somewhat ruefully backs away from that rule, saying that the 10,000-hour mark Gladwell chose was arbitrary. While hours spent matter, Ericsson said he is much more concerned with the type of practice. Mere repetition, he says, without focused analysis and improvement, is often pointless, no matter how many hours are spent.

In Peak: Secrets from the New Science of Expertise, to be released next month, Ericsson offers a model based on over 30 years of studying extreme performers in memorization, sports, classical music and chess, as well as in more applied fields such as medicine and computer science.

Ericssons approach to developing expertise centers on two concepts: deliberate practice and mental representations. Deliberate practice is an extremely focused effort to improve at the edge of an existing skill level the point where you are barely comfortable, often succeeding but still often making errors. It usually requires a coach or teacher, with immediate feedback, reflection and correction for error. As experts push to the next level, they develop and ingrain mental images of the skill or process, which then become literally embedded in the brain.

We recently spoke with Ericcson by phone to discuss what hes learned about becoming an expert in just about anything.

Question: You begin the book by noting that Olympic athletes who held many world records 100 years ago would be mediocre in their own sports today. And you suggest that, even with sports, what was previously an art became a science in terms of how training is conducted. Some would barely qualify for events they once dominated.

Anders Ericsson: Yes, athletes today far outperform their counterparts of 100 years ago, and this results from a transformation in training methods. If you look at long-distance running or skiing, for example, I think youll find that it was only the middle of the last century when they discovered interval training, which allows the athlete to push the system. They used to just go out there and just run for a really long time. If you really want to improve speed, you need to do interval training, running much faster than you can possibly sustain, and then you slow down or walk to recuperate and then make another push at high-level speed.

Question: Edwards Deming, as you know, used engineering feedback loops to winnow out errors, a method credited with sparking the quality revolution in Japans auto industry in the 1950s. Do you see a resonance between your deliberate practice and Demings model of continuous improvement?

AE: I think feedback is at the heart of any effective learning process. Deming was doing this with machines and engineering. Once you can measure performance, you can measure discrepancies. The difference is that we are dealing with human performance and what people can do with mental representations. In Demings case there were limits on engineering. But when you are looking at expertise, the remarkable thing is how the brain can monitor itself and learn to reach the highest level of performance.

Question: You focus a fair amount on brain science. Could you comment on how deliberate practice changes the brain?

AE: A lot of people agree that a childs brain could change as it matures. But there was a lot more argument about to what extent an adults brain could really change. We focus on the cab drivers in London, who have the incredible task of memorizing London so that they can, if asked, take a passenger from one point to another point in the most efficient way. It takes many years for someone to pass that exam. When they did brain scans on those who had passed this exam, their brains were different from controls, including those who began the program but dropped out.

Question: Could you define mental representations in a nutshell?

AE: Skilled musicians when they first read the notes can form an image of how they want the music to sound, inside their heads. Then they can work during practice toward the sound they want to create. Chess masters do something similar. They dont have to see a board. They can keep it in their heads and manipulate moves. That mental work is part of what defines expertise.

Question: You talk about chunks and patterns and being able to recognize those and use them to create lines where others see only scattered dots.

AE: A chess expert will actually see relationships among the pieces that a novice will not see. Another example is that when you read English texts its relatively easy to repeat a sentence you just read. But if you scramble the words and ask people to repeat them in scrambled form, people can only repeat back a few words. Pattern mastery allows the listener to track complicated spoken language, and the same is really true about most difficult skills.

Question: You have a mantra you offer for those who want to implement these principles on their own: focus, feedback and fix it. But you also say that practice is not fun.

AE: If you want to really improve, and do something that you currently cant do, you have to stretch yourself. And that seems to require full concentration. People who have a hard time concentrating dont enjoy this. Skilled individuals are so focused on achieving this goal, they pretty much dont notice the intense concentration. But even the experts can only do this for a limited time, and we found that they pace themselves so they only train for four or five hours a day, even at the highest levels.

Question: You describe in the book how Benjamin Franklin taught himself to become an exceptional writer. Could you describe that briefly?

AE: Franklin found short articles in weekly magazines. He would read the article and then a few days later try to reproduce that text. Hed then compare it to the original and see where he needed to improve. Then he would tackle a new article. He found that he got better and better at reproducing the arguments, and that his own writing became more effective as he fixed the model within his own mind.

Question: You argue that in nearly every case, including Mozart, prodigies actually reflect intensive training at a very early age. If there were a lot of prodigies lying around, would that spell trouble for your theory?

AE: Our claim is that exceptional performance is acquired and demands a long preparation period. So if you can identify individuals who perform exceptionally without any training, that will be a problem for this theory. Ive been spending 30 years looking for counterexamples. It seems that people believe so strongly in talent that they dont look closely at these cases. Very often parents are working very closely with the children, and they have a very different educational environment.

Question: And sometimes that kind of parental pressure backfires.

AE: Its key that the child is motivated and a partner rather than a slave of the parents in training. We know that a lot of these prodigies do not become successful as adults. Too often, the parents dont allow the children to progressively take more charge of their own learning. Theyve depended completely on their own parents. Were trying to emphasize the importance of personal motivation. In my own career, Ive always asked what I enjoy doing and what I want to work on, and once I have the motivation, then finding ways to improve becomes meaningful personally.

Question: Taking your book as a whole, it seems the message is not that you should become a phenom, but that whatever time you do spend at the piano or golfing, you can use these principles to improve your game, rather than sitting on a plateau.

AE: I agree. These principles are effective even if you only want to spend 10 to 50 hours to improve your current performance.