"No two brains," suggests Brain Technologies Corp. President Dudley Lynch, "select, process, store or retrieve information in the same way. How it does what it does has a direct effect on our intellectual response, emotional state, sense of values and decision-making ability."

Most people, says Lynch, tend to use one of the brain's four quadrants more than the other three, and, depending on the predominant quadrant, recommends specific exercises to enhance and maintain brain tone.

Lynch terms the four quadrants BrainFrames. The quadrants and qualities they represent:

The "I-Control" individual (left front quadrant): methodical, sequential, predictable, realistic, balanced and rational. Exercises: Write a book; learn to program a computer; teach a course; plant and maintain a garden; start a collection such as stamps or autographs. Typified by Pope John Paul II, author-historian Barbara Tuchman, the late Chicago mayor Richard Daley.

The "I-Explore" individual (right front): change-oriented, experimental, imaginative, a dreamer, a variety seeker, idea-oriented, a synthesizer. Exercises: Take up a hobby -- photography, painting; go exploring; write -- poetry, fiction; do physical activities by yourself -- walking, jogging, bicycling; play a musical instrument; meditate. Typified by astronomer-author Carl Sagan, writer Erica Jong, San Francisco Mayor Dianne Feinstein.

The "I-Pursue" individual (left rear): mobile, decisive, practical, adaptable, productive, enthusiastic. Exercises: Run for office; compete in or referee a physical sport; train animals; play board games requiring instantaneous decision-making; manage a community project; act, dance or do aerobics; start your own company. Typified by Chrysler Corp. chief Lee Iacocca, athlete Mary Lou Retton, football great Joe Namath.

The "I-Preserve" individual (right rear): stable, direct, an idealist, emotional, a defender, sentimental, spontaneous, a traditionalist. Exercises: Spend more time with people you care for; help others in need; keep a diary or daily journal; regularly list your likes and dislikes; become involved in humanitarian activities. Typified by former secretary of the interior James Watt, singer Pearl Bailey.

Lynch evolved his BrainFrame system after studying research by sociologists and a number of medical experts, among them Dr. Antonio Egas Moniz and Dr. Roger Sperry, both winners of the Nobel Prize for Medicine for their work on the brain and brain tissues.

Eventually, Lynch came up with what he calls the BrainMap, "a brain & strategy self-assessment profile." Popularity of the BrainMap led to two other self-assessment tests -- the Couples BrainMap and MindMaker6 -- plus a book, Your High-Performance Business Brain: An Operator's Manual, and a newsletter, Brain & Strategy.

"The world we now inhabit," he says, "is requiring the brain to be increasingly adept. What we are trying to do is help people teach their brains, use their brains, to react to the world in different ways."