The best books about the nature and capacities of our bilateral minds

Utilizing data from split-brain patients (whose left and right cerebral hemispheres had been surgically separated), the authors of this book focus on how our “two minds” yield a unitary consciousness.

This is the book that first lit the fire of inquiry for me. The whole idea was to understand the “integrated” mind by first understanding the minds of individuals that had been divided by severing the corpus callosum (which connected their two cerebral hemispheres) in order to alleviate medically intractable epilepsy.

It was suggested that in such individuals, their “minds” were divided as well. Yet some later studies did suggest that some intercommunication (through other channels) did survive.

A comprehensive account by a pioneer of the discipline.

This book provides an overview of the relatively new discipline (in 1975) of “cognitive science,” so much so that I wondered whether I should have switched over from philosophy (I did not). It displays the breadth and depth of the discipline, which convinced me that one could no more be an expert in cognitive science in general than an expert in physics in general, biology in general, or philosophy in general.

This book is certainly a must-read for anyone interested either in the discipline itself or even in a corner of it, such as human brain laterality. (Be sure to see “hemispheres” in the index of this book.)

This book, more than any other on the subject, surprised and fascinated me.

Its thesis is deceptively simple. It suggests that the two hemispheres of the human brain were “strangers” to each other early in our evolutionary history (three millennia ago). The left hemisphere received the information from the right as a message from an unfamiliar source (an unseen “voice”).

Jaynes proposed that this was the basis for all religious experience. It was our intuitive right hemisphere that supplied the “voices” of the gods. True human consciousness only arose when this bicameral mind “broke down” and the “voice of God” was replaced with what had been speaking to us all along, the other more intuitive half of ourselves.

This is an expansive treatment of the intellectual and cultural ramifications of the bilateral mind from ancient times to the present. The dominance of the analytic left hemisphere (the “emissary”), McGilchrist fears, threatens to usurp its experience-grounded “master” – to the detriment of human culture.

While The Master and His Emissary and The Origin of Consciousness cover similar topics, it is interesting and important to note that there are areas where their perspectives complement each other and those where they differ, such as their accounts of schizophrenia. I still find myself vacillating between the two. I sometimes wonder whether my indecision may itself be the result of my own hemispheric split.

One could almost have predicted that the concept of brain laterality would provide material for explaining the division between the political left and right.

Do political conservatives and liberals have brain differences that may, in part, determine their politics? This volume is valuable as a rare source of material for addressing this question. Political conservatives apparently have larger amygdalas (which register reactions to threat), while liberals may have a reverse valuation. These two brain features may contribute to determining hemispheric preferences.