In the olympics, studies have shown that those who practice mentally (visualization, psychology, self-talk, etc) as well as physically (actual physical training) do better than those who just grind it out on the training field.
In a sport where there is a fusion of man and machine, it is even more important to "Maximize Your Racine Performance" by adhering to the strategies such as what Ross Bentley has outlined.
If you're a driver who has reached a plataeu and can't seem to improve, there's a great likelihood that it's not more practice or track time that's needed -- but more mental practice. And that's cheaper, too!
Ross outlines great mental techniques in this book that are easy to follow, and very applicable to the sport of race car driving.
For a bigger picture on Mental Training, I urge to to also look at Ken Baum's The Mental Edge. Then make sure you have this book by Ross to have mental training specific to race car driving.