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Tuesday, May 09, 2017

The Master and His Emissary - A Review of the Divided Brain

Originally published on 5-14-14:

Like many, I've been skeptical of left / right brain theory for decades.  The data seemed fluffy, with too many exceptions.  Then I encountered this video of a TED presentation:




Finished?  If you're like me, the value and concentration of the content were overwhelming.  But watch it again.  This time keep your hand on the pause button.  Pause if his words get ahead of the pictures.  Pause again if the pictures get ahead of the words.

Yes, there's a lot of detail here, both in hard data and concept, but that's not the main reason for this second viewing.  This video nicely demonstrates the theme of its own content.   It's been biologically established that as you watch, the presentation is going into BOTH sides of your skull at the same time.  Your eyes and ears are collecting two similar copies, but your divided brain is creating two DIFFERENT experiences, one dominated by image and animation, the other by text and verbal logic.  Your brain is running in parallel, and the only time you notice is when one half's recognition gets ahead of the other. Your control of the pause button shifts smoothly from side to side.  Your left or right brain inhibits the other when needed.  This shifting control allows both experiences to be captured.

The moving images provide right-brain meaning through visual metaphor. Dr. McGilchrist's precise left-brain verbalization and text nail down and allow you to "grasp" these ideas. Though I'm over-simplifying, this is an example of the very thing being presented - that it takes BOTH sides of the brain working as asymmetrical and largely unequal specialists in delivering the result that is ultimately the human mind.

The other reason this video is important is that the book is extremely detailed and thoughtful.  "The Divided Brain" takes some digesting.  But it's worth it.  And it's good to have a "both-brain" outline to fill in his very deliberate, precise and comprehensive written presentation.   This video covers literally 500+ pages which are well summarized in only a few minutes. Much of it is profound. I watched it at least a dozen times. Then I read the pages:

The Master and His Emissary: The Divided Brain and the Making of the Western World, by Dr. Iain McGilchrist



The Divided Book

This work is both brilliant and maddening.  What it presents is a major advancement in our ability to understand human behavior and our behavior's contradictions.  It contains both hard data and insightful observations, but also wild conjecture. From a wealth of brain studies over the last few decades, the author has crystallized a new model of left and right brain functionality, which is by far the book's greatest contribution to the topic. Then he describes the left brain's evolving impact on western culture.

The result is both logically and intuitively convincing.  Each of us is literally of two minds, creating a single subjective experience.  We are driven by two largely complimentary engines of evaluation, each seamlessly yielding control of the mind and body from moment to moment depending on which side is most likely to be effective in dealing with the current challenge.  Asymmetry of functional realms is the key to minimizing obvious dynamic conflict. The realization of this fact has wide-ranging implications for all of human behavior, but especially personal relationships, politics, religion, and economics. I shall address these consequences in separate blog posts. But let's get back to the book.

The delivery of these ideas is fascinating in spite of his formal style, which is necessary for such a demanding topic.  Dr. McGilchrist does an amazing job of precisely navigating very deep waters, but like any project this ambitious, he reaches a bit too far now and then, which is perhaps his most important lesson. This work spans credibility from solid conclusion to obvious speculation.  But even in speculation, there is very little that is patently wrong.  These ideas are not some new-age theory, though this book may literally become the bible for left / right brain enthusiasts.  No, I haven't lost my bias for the rational, but I have gained a new appreciation for the intuitive, and it's genesis.

Like the brain, the book is presented in two parts.  The first part is well-founded scientific documentation of the physical and behavioral differences between the left and right brain. Taken alone, it's of tremendous value in understanding the brain's obvious bicameral nature.  The second part is dominated by the selective ascription of art and history to one side of the brain or the other, and its impact on our modern culture.

Though dense with useful data, each chapter raises important issues, which are then addressed by the next. Step by careful step, he builds a coherent model of the mind based on cross-supported observations of brain physiology and actual human behavior.  For the most part, it rings true.

The later section on paradox is brilliant, and sets the stage for what he presents in the second part: the "Achille's heel" of the rational mind, which is that our more logical left brain denies anything not within its framework of simulation. This means that the left misses a lot, virtually anything that can't be "proven".  He describes this shortcoming as a hall of mirrors.  A sharp focus and "single-minded" objective is the left's strength, but also its weakness.  The left brain is blind to, or otherwise demotes obvious leaps of intuition, such as casually stepping over a paradox.  He uses Zeno to nicely make this point.

The second part of the book is all about the impact the left-brain has had on the realm of the right.  He uses examples of music, art and philosophy from the last few thousand years.  Much of this is based on McGilchrist's impressive knowledge of our culture, and some intuition.  This part is as subjective as the first part is objective.

The first half of the book is a pleasant intellectual challenge.  It's also a ride in the park compared to the second half, which is like hitting a bog on a dirt bike, well at least it was for this rational mind. I had to gear-down even to drag my way through, probing for the hard ground of logic, and finding little.  He seems to ascribe behaviors to one side of the brain or the other almost willy-nilly.  And he freely admits, "These thoughts are inevitably contingent, to some extent fragmentary and rudimental."  Though I tried to understand his literary leaps, my mind kept reverting to the rational. This probably says more about me than the writing, but I wonder how many other readers gave up at this point and never finished the book.

To be fair I chased down a few of these wild ascriptions using his comprehensive bibliography.  Each provided a reason to believe, if not actual proof.  You'll have to decide for yourself. Though useful data are more rare in the second half, if you grind through, the pearls are there, and worth the effort. Plus there's something more useful than merely data.  If you tend to the rational, the first half will be the most meaningful. If you're more intuitive, I suspect the second half will be the most insightful. This intuitive approach in the second half also creates doubt in the rational mind.  For me, conjecture about so much subjective art, and evidence such as which way a subject of a painting was facing, left my mind reeling and yearning for the science of the first part.

Another way of saying this is that the first part contains lots of observations, science and hard data.  It makes sense.  It makes you THINK.  The second part makes you wonder about the validity of the author's many right-brain speculations.  And it gives you the FEELING he just MIGHT be right - but he can't prove it.


Conclusion

Dr. McGilchrist presents a rational left-brained model for what our right-brain has secretly known all along, but could not say.  Our right side feels the truth of the presentation, but doesn't have a voice. Our left side can put it into words, but won't accept a new model of the mind without reasonable proof.  This book provides both proof AND conviction. It makes you think.  And it makes you feel.

This is where the parallel with the video comes in.  The book is also a Rorschach's test of left and right brain conclusions.  The medium IS the irony.  Though the book is mostly words meant for the left brain, these words are inspired by right-brain imagination.  Though tedious at times, even the more wild ideas are hard to indict.

I've probably re-read fewer than ten books in my entire life.  I'm a slow reader, but once I read a book, I know it.  This book is an exception.  The moment I finished (and it took months), I flipped to the front and immediately started reading again.  Like the video, reading the book whet my appetite for more.  Perhaps it'll do the same for you.  If you have ANY interest in the brain or human behavior, "The Master and His Emissary" is a must read.

05-09-17 An excellent interview of Dr. McGilchrist