"Her purpose here is to discuss and illustrate the four types of brain waves--beta, alpha, theta, and delta--with emphasis on what they do, how they work together, and whether we can use their power."-- Booklist . About the Author: Anna Wise, author of The High-Performance Mind , has taught meditation and brain-wave development for three decades. She leads workshops, seminars, and corporate-training programs worldwide. In 1988, she founded The Anna Wise Center in Larkspur, California.