Dalhousie University, Halifax, Nova Scotia

“If the only tool you have is a hammer, you tend to treat everything as if it were a nail.”

Maslow A. (Psychology of Science, 1969)

In this article, I would like to attempt to share with your readers the contemporary research dealing with the “split brain patients.” Educational implications of this theory will also be attempted. The real beginning of this research started back in 1950’s when Dr. Roger Sperry and his associates began “split brain” experiments on animals. When they cut all connections between the two hemispheres of cats or monkeys, they found that the animals remained remarkably “normal.”

In human beings, cerebral cortex consists of two identical hemispheres (Left H; Right H). They are exactly alike in appearance and contain identical control centers for sensory and motor activities of the body. Furthermore, the left hemisphere controls the right side of the body and the right hemisphere controls the functions of the left side of the body.

The two halves of the brain have a kind of partnership, in which the left brain handles language and logical thinking, while the right does things that are difficult to put into words. But it must be stated that each half of the brain has its own separate train of conscious thought and its own memories. The left brain tends to think in words, the right brain thinks directly in sensory images.

The human brain should not be seen as a passive three block sponge soaking up a flood of information. Instead, it should be seen as an active seeker of information which it then filters, processes, encodes, and organizes into complex hierarchical schemes. The brain is capable of creating intentions. It can then form plans and programs based on these intentions. It can regulate its own behavior so as to bring conformity to these plans. It can also verify its activity by connecting any mistake it has made.

Dr. Blakeslee, writing for his famous book The Right Brain (1980) has brought the following findings to our attention:

  1. Left brain abilities in right handed people are speech, reading, arithmetic, writing, verbal memory, abstract categorization, seeing more than one thing at a time and attention for details.
  2. Right brain abilities are spatial, perception, ability to “find way”, visual musical sense, facial recognition, understanding metaphors, and emotions.

About 10% of our population has .been genetically left-handed since the Stone Age. In other words, the right brain dominance which leads to left handed men is genetically present in 10% of our population. About 70% of the right handers seem to have language dominance in their left hemisphere. The other 30% either have language in both hemispheres or have it only in their right hemispheres. For lefthanders who want to know which hemisphere of the brain carries their language ability, Dr. Levy of Chicago University has devised a very simple test.

  1. The left handed subjects who write with an inverted hand had language in the left hemisphere and spatial ability in the right hemisphere.
  2. The left-handed persons who write noninvertedly have language in the right brain and superior spatial ability in the left.
  3. The right handers who are noninverted writers have language in the left hemisphere and _ spatial ability in the right hemisphere.
  4. The right handers who write with an inverted hand show language in the right brain and superior spatial ability of the left. Then four points are graphically described in the following diagram.

Diagram at the Left Sandra Witelson and Jerre Levy, two famous female neuropsychologists have come up with some disturbing findings regarding the gender of the person and his/her brain functioning. Blakeslee writing for his book “The Right Brain” (1980) comments:

“While the sex and left-handed men may seem like strange bedfellows, they do have something common when it comes to lateralization. All the tests that demonstrate left right differences in brain organization give weaker results when they are given to women and lefthanders. The clear implication is that women and left-handed men are less lateralized. Reduced lateralization has both good and bad effect on mental abilities.”

Dr. Levy, a female neuropsychologist, through her intensive research has found that:

  1. Males are superior to females in map reading, three dimensional visualization, understanding of physical principles and mathematical reasoning.
  2. Females surpass males in reading skills, verbal fluency, fine visual details, incidental memory, associative memory and understanding social relationships.

It must be pointed out that the two sexes do differ in their brain asymmetry which develops through the interaction of biological predispositions and environmental interactions.

The above discussion leads to the formulation of the following points:

  1. The cerebral cortex of the brain is divided into two hemispheres, joined by a large bundle of interconnecting fibers.
  2. The left side of the body is mainly controlled by the right side of the cortex and the right side of the body by the left side of the cortex.
  3. The structure and the function of these two half brains, in some part, underlie the two modes of consciousness which simultaneously exist within each of us. The left hemisphere is predominantly involved with analytic, logical thinking, especially verbal and mathematical functions. It processes information sequentially, staying at a linear level.
  4. The right hemisphere seems to specialize for holistic mentation. It is responsible for our orientation in space, artistic endeavors, crafts, body image, and recognition of faces. It processes information simultaneously and holistically.
  5. The research findings are pointing to the direction that women and left-handed persons, through the socialization processes, become less lateralized in our society.

We possess two cerebral hemispheres, which take turns to become dominant, depending upon the task at hand, has tremendous educational and personal implications. This may be the cause of fundamental duality of our consciousness. It may also account for the Freudian “conscious” and the “unconscious” mind. This may also explain why we undergo a daily struggle between our “head” and our “heart.” Over reinforcement of our hemisphere may lead to the production of a particular type of personality in children and adults.


Because the lateral specialization of the brain is unique to human beings, we do become capable of producing symbols, a species specific behavior residing in our left hemisphere. ‘

Our schools attempt to develop the left side of the brain which deals with reading, writing, spellings and arithmetic. The nonverbal side of knowledge is mostly ignored. But the fact of the matter is, that, a person’s success in the world is largely dependent on how much his intuitive side (right brain functioning) has accidentally developed.

The left-brain takeover of education has resulted in a sort of academic dream world in which purely left-brain thinkers admire each other’s “scholarliness.” Our universities, by reinforcing left-brain learning, produce graduates who are habitually “‘left brained scholars.” To last in such a system one has; to become more “scholarly”. And less intuitive. We; should ask our educators to put equal emphasis on verbal rationality: and, nonverbal intuitive mode of thinking. A real reform of our educational system will take place only if the teachers and parents learn to understand the true duality of their children’s mind. An imaginative teacher can bring about the left right brain synergy by presenting his material through both the modes of consciousness.

Modern technology can help us to present the material to both sides of the brain. Visual aids should supplement pure verbal presentation. Pictures, videos and movies can be used to visualize difficult concepts.

Multiple choice exams encourage memorization of the concepts. It is a known fact that when the problem is reduced to eliminating three out of four possible answers, right brain dominant students suffer.

Computers which can produce one step at a time strategy are essentially an extension of left-brain revolution. They are very useful in extending our ability to do abstract thinking but it must be pointed out that they are hopelessly inadequate in teaching the kind of thinking that is done by the right brain.

Coniputers are going to make many pure left-brain clerical jobs obsolete. Schools and universities along with teaching the student the use of the computers should also develop creativity and holistic thinking. In other words they should stop producing “human computers” with “atrophied” right brains. The “feeling” side of life has become more important than the intellectual side, if we want to survive as a race.

National education survey in the U.S.A. (1977) has found that the majority of teachers were dissatisfied with their jobs. They also found that despite higher salaries and improved working conditions morale of the teachers was at its lowest in years. Furthermore, they are kept busy with housekeeping chores that the actual teaching time per day per teaching day is reduced to ninety minutes a day. As Dr. L.A. Hart, writer of “Human Brain and Human Learning” (1983) comments:

“My own observations suggest that when classroom instruction is measured on a stop watch basis, including the time that goes to disciplinary remarks, or action, class management, giving out and collecting things, housekeeping, tests and examinations, clerical matters, internal and outside interruptions and so on, the net teaching time shrinks to 90 minutes a day and often far less.”

Further studies have demonstrated that these ninety minutes are mostly spent by teachers toward the verbal analytical tasks. It is suggested that left brain activities should be augmented by intuitive tasks. The children should be taught to think “musically” or “think visually” rather than memorize verbal rules to pass verbal tests. In other words, they should learn to experience the nonverbal consciousness, imagery, verbal fluency and master the divergent production of creative ideas. The habits of creative thinking should be taught along with the +8Rs. Material should be presented in such a way that it is learned by both sides of the brain.

I would like to end this article with two quotes. The first one is from a Yogic philosopher Aurobindo (1910) and the second one is from Tagore the great Indian poet.

The intellect is an organ composed of several groups of functions, divisible into two important classes, the functions and faculties: of the right hand, the functions and faculties of the left. The faculties on the right(sic) hand are comprehensive, creative and synthetic; the faculties of the left(sic) hand critical and analytic … the left limits itself to ascertained truth, the right grasps that which is still elusive or unascertained. Both are essential to the completeness of the human reason. These important functions of the machine have all to be raised to their highest and finest working power, if the education of the child is not to be imperfect and one-sided. (Aurobindo, 1910).

A teacher can never truly teach unless he is still learning himself. A lamp can never light another lamp unless it continues to burn its own flame. A teacher who has come to the end of his subject, who has no living traffic with his students can only lead their minds, he cannot quicken them. Truth not only must inform, it must inspire; if the inspiration dies out and the information only accumulates, then truth loses its infinity. The greater part of our learning in the schools has been wasted because for most of our teachers their subjects are like dead specimens of once living things with which they have learned acquaintance but no communication of life and love. Sir Rabindranath Tagore.

Article extracted from this publication >>  June 28, 1985