EVOLUTION: INTELLIGENCE AND CREATIVITY

INTELLIGENCE AND CREATIVITY

Intelligence and creativity are both dependent on brain power but are not equivalent to one another.  Intelligence is more related to brain capacity for storage and recall of information and wise application of that capacity.  Creativity is less related to capacity than it is to unprecedented application of existing capacity.

Intelligence is more likely to be thought of as residing in the left brain, and with language and linear thinking, such as dominates in mathematics, is processed in the non-visual part of the cerebral cortex.  Conversely, creativity seems to reside in the right brain where spatial, visual, and global thinking is processed.  The highest functional state of both intelligence and creativity occurs when the opposite sides are compatibly working on the same project.  Sometimes that may require a highly disproportionate amount of work for a particular side.

EVOLUTION OF BIG BRAINS

Big brains are correlated with big bodies, but the correlation is not 100%.  Small brains can be associated with remarkably complex behavior as anyone who has studied ants and other tiny animals may know.  The driving force for the large brain is not behavior, but seems to be the need for large brain capacity to process visual information.  The transfer of the image from the retina to the brain uses fibers that covey information as while keeping a spatially correct flow of the visual signals.

The lens of the eye focuses the corresponding image of the arrow on the retina in reverse (as shown and inverted as not shown).  The optic nerve portions shown partially cross-over for processing on the opposite side of the visual cortex in the brain.  The extreme outer parts of the object form the inner part of the retinal image that goes to the outer part of the visual cortex and is not duplicated as are the inner parts of the object image.  The figure above of Cajal, 1899 can be found in Polyak, 1957.  [Polyak, S.  1957.  The Vertebrate Visual System.  Univ. of Chicago Press, Chicago.  1390 pp.  Pages 781-791 discuss crossing over in the visual system with several diagrams from S. Ramon y Cajal, 1899.]

If your eyes are focused on an edible morsel, the visual image involves many sensory nerve fibers.  When the brain makes the decision to pick up the morsel, the complex movements require many fewer motor nerve fibers for the coordinated action of muscles to make the fingers pick it up.

Although the growth of the visual cortex to accompany better eyes may have been the major selective force for evolution of larger brains, the enlargement of all of the cerebral cortex was beneficial so there was less selective force for keeping the non-visual part small.

 WHY I STARTED THINKING ABOUT THIS TOPIC

After twenty years of teaching primarily invertebrate and aquatic biology type courses, about the year 1980, I was called upon to present the zoology portion of the introductory course sequence.  As I was preparing to present a lecture on the brain and nervous system my curiosity about the evolution of things made me want to explain why damage to the left side of the motor region of the brain is reflected in paralysis of related muscles of the right side of the body.  It was apparent the cerebral processing of vision kept the related motor processing on the same side for greater efficiency and the the crossing over to the opposite side for motor nerves occurred further down the brain stem.

Studies of paired molluscan nerves with right and left tracts corresponding to the right and left portion of our spinal cord had been shown to have association neurons in successive ganglia that could transfer information around a break in one half to bypass the break.

ASYMMETRY OF THINKING - LEFT BRAIN, RIGHT BRAIN

The symmetry of vision and its processing in the brain is most efficiently accomplished by the crossing over of the optic nerve fibers going from eye to brain.  There is no such need for symmetry in the brain when it comes to language or linear thinking in the brain, nor is there such a need for global thinking or other non-linear aspects of thought.  So an area of the brain thinking about something does not need a duplicate but reversed thought on the other side.

Many, if not most, thoughts do not depend on coordination of left and right brain.  Thus the one who is concentrating on a visual concept may have difficulty finding the right words to express it.  And the one eloquent and efficient in linear thinking may have difficulty understanding or expressing the spatially significant part.  Fortunately, most things have a bit of both types of thinking involved so the brain gets training that can make intelligence or creativity more evident.

IS THERE A SPIRITUAL PART OF THE BRAIN?

Most linear thinking has a spatial component, and spatial things have verbal and  mathematical components.  But God and spiritual things are not so simply analyzed.  No physical parts but infinite power, extent and grandeur are hard to grasp mentally and impossible to grasp physically.  So maybe that indicates a spiritual part to us that makes us capable of such transcendent thoughts?

Joseph G. Engemann     July 25, 2014

SCIENCE: QUIET AND CREATIVITY

QUIET - the book

Cain, Susan.  2012, 2013.  Quiet, the Power of Introverts in a World That Can’t Stop Talking.  Broadway Books.  New York.  352 pp.  Just read this book at the end of January 2014.  Very worth reading.  Today (February 2, 2014) I was reviewing in my mind some of the things from it I wanted to blog about (evolutioninsights.blogspot.com) and, as I was thinking about how creativity is enhanced by left-brain/right-brain cooperation and how creativity seems to be associated with introversion and right brain activity, the following seemed evident.

INTROVERT-EXTROVERT-AMBIVERT RATIO

Cain discusses probable causes of introvert/extrovert personality types and sees both hereditary and environmental factors as causes, including one known gene, as having some influence.  I see that a simple explanation of chance expression of left brain versus right brain dominance could be a major factor.  Once both hemispheres are more equally integrated into brain activity, one might be more of an ambivert.  Until that point is reached the ratio early in life would be close to 1:1.  

CREATIVITY

I agree with her arguments that introversion is associated with the careful thought leading to creative results.  But I have personally made the transition from right brain dominance and introversion to either extroversion or, more likely, ambivert status.  I still find quiet time pleasant and useful for thinking.  My discovery of my transition was a few dozen years ago as I was reflecting about left-brain/right brain matters and the need for me to use more graphic material in lectures to accommodate those students who were right-brain dominant.  I became aware that I was thinking in words that I was hearing in my mind.  At that time I could not visualize a picture of anything in my mind, the same mind that in the mid 1960's I could visualize strategy for a three dimensional tick-tac-toe game that some faculty were playing on Western Michigan University's new IBM 1620 computer.  I had lost my first game with it, but, after a night's interrupted sleep pondering it, I won the next game.  I had changed.

HEMISPHERIC DOMINANCE AND CAREERS

I spent some time considering a research project enlisting honors college students in a longitudinal study of hemispheric dominance.  A math professor friend noted the mathematicians had been discussing left-brain dominance as characteristic of their profession.  But he was right-brained and taught an area of math more visually oriented, I think geometry.  I wanted to have students check the ratio in various academic disciplines, both in faculty and undergraduate majors.  In particular, follow-up on students from their freshman year to later years would show whether they should be counseled out of a field or left to make the transition to suitable hemispheric activity.

I did not pursue the project, perhaps because I was an INTP personality type, and/or I didn't have the disposition to deal with the ambiguities involved in getting approval from the university's human subjects review board as needed for projects when people are the subject.  But from personal experience, I knew that I changed.

My understanding of the evolutionary origin of hemispheric dominance in humans came with my being called upon to teach introductory zoology about the end of the 1970's.  After 20 years teaching invertebrate type classes I wanted to know the reason the left brain controls the right side of the body and the right brain controls the left side of the body.  To shorten the story, it wasn't in the books, but it became apparent that it was the most economical way to integrate vision into a unitary binocular vision for us.  The role of association neurons connecting left and right neurons controlling structures of invertebrates contributed to the answer.  I gave a presentation at the state academy on the topic but did not publish the story.  The enormous demands of brain space for good vision selected for a large visual cortex.  But the area for nervous control of the physical body do not demand much space for transmission of motor impulses.  So rather than having massive crossing over from both visual hemispheres, the partial crossing over of visual and complete crossing over for motor nerve enervation was achieved through natural selection.  As other portions of the brain enlarged along with the visual cortex, the portions allocated to thought did not have right and left functions so opposite sides of those regions could specialize as we see in humans.

CONCLUSION

Both personality types may have creativity in their future as they optimize hemispheric use with a balance appropriate to the business at hand.  I might never have reached this understanding if my nine-year old verbal brother had not belabored his tongue-tied little five-year old brother with the maxim that if you couldn't express your idea you didn't know it.  I was not literally tongue-tied, but I clearly understood concepts I could not find words to express.  My transition from introversion to what I am today is a long story, I will spare you the details.

My understanding of hemispheric dominance and creativity long ago was why I argued study of biology was exceptionally important in a liberal arts education.  Laboratory and field study of organisms exercised the right brain and explaining and describing exercised the left brain; cooperatively using both sides enhanced the result.  Actually, any subject that has physical aspects and written and verbal aspects should have similar value.  

Perhaps the link between left-brain with math, music, and speech skills, versus the right-brain with visual, graphic, and mechanical skills starts early in life.  It may never be known if more right-brained children developed after television began to replace radio.  But there are good reasons to think both physical and mental health are enhanced by adequate diverse physical exercise.  Where do smell and aromatherapy fit in?  We are complex creatures in a complex world; I will leave it at that.

Joseph G. Engemann      February 2, 2014