The Neuro-Physiological Foundations of Dual Motive Theory: a Review of the Brain Model

THE NEURO-PHYSIOLOGICAL FOUNDATIONS OF DUAL MOTIVE THEORY:

A REVIEW OF THE BRAIN MODEL SET FORTH IN WILSON AND CORY'S THE EVOLUTIONARY EPIDEMIOLOGY OF MANIA AND DEPRESSION (2008)

A paper prepared for presentation in the Dual Motive session IAREP/SABE 2008, World meeting at Luiss, Rome September 3-6, 2008

Bhagat Patlolla, MD Odessa Medical University Research Associate, Bioengineering (Stem Cell Research) Stanford University

The Evolutionary Epidemiology of Mania and Depression: A Theoretical and Empirical Interpretation of Mood Disorders. Mellen Press (2008) is co-authored by Daniel R. Wilson, Chair of Psychiatry, School of Medicine, Creighton University, and Gerald A. Cory, Jr., Senior Fellow, Graduate Studies & Research, San Jose State University. Wilson, who also serves as Professor of Anthropology, is a pioneer of the newly emergent discipline of evolutionary epidemiology and author of numerous scientific publications on that subject. Cory is well known for his innovative applications of neuroscience to economics and the social sciences in numerous recent books, articles, and scientific papers.

The book represents a provocative new approach to the understanding of not only mania and depression, but provides a general theory of normality for psychiatry and related sciences. It further provides a physiologically sound platform for the linking of the biological sciences with the social sciences, especially economics, sociology, and political science. Such linkages hold the potential to provide valuable new insights into all phases of human social behavior from one-to-one personal exchanges to behavior in groups and larger organizations.

In beginning this review I follow the prepublication evaluation provided by Kay Redfield Jamison, Professor of Psychiatry, Johns Hopkins University, who is a leading scholar on mood disorders and author of the best-selling An Unquiet Mind, an influential, popularly accessible, and very humanistic presentation of the human impact of mood disorders. Jamison writes as follows:

This is a fascinating and important book about a topic of immense medical, scientific, and humanistic importance. The authors have put into an overarching theoretical perspective disorders of mood that affect tens of millions of individuals and society itself.

1 The overarching theoretical perspective that Jamison refers to, and which largely constitutes the chapters of Part I, is a model of neural architecture, the Conflict Systems Neurobehavioral (CSN) Model or Complex, developed by Cory at Stanford University (1974) and elaborated by him in numerous recent publications applying it to economics and the social sciences (e.g., Cory 2008ab, 2004, 1999). Cory's CSN Model, although developed independently, was later adapted to a modified and updated version of the late Paul MacLean's tri-level evolutionary concept of the brain.

Sadly for science, in some narrow quarters of neuroscience, the tri-level concept of MacLean, who was for several decades head of the Laboratory of Brain Evolution and Behavior of the US National Institutes of Health, has been gratuitously and unjustifiably referred to as "outdated." Such statements are clearly based on transient, trivial, nonscientific issues of "fashion" and general ignorance of his work rather than good science. MacLean's work, especially his masterwork of 1990, The Triune Brain in Evolution, constitutes a seminal, comprehensive, and guiding framework for medical physiology, psychiatry, and especially the emerging disciplines associated with evolutionary neural physiology and evolutionary epidemiology. Recently, numerous works testify eloquently to the currency and importance of MacLean's work. Among such works are, not only the present work, but an entire issue of the journal Physiology and Behavior (2003) and a comprehensive and influential volume, The Evolutionary Neuroethology of Paul MacLean (Cory & Gardner, 2002). Both report the contributions of numerous outstanding scholars applying insights gained from the MacLeanian perspective. Other recent works, too numerous to mention here, support the currency and importance of MacLean's work (e.g., see also Panksepp, 2002).

The CSN Model takes an evolutionary perspective and rests primarily upon the well- established taxonomic fact that we humans are mammals. The CSN Model is based upon the evidence from a large body of physiological and medical research on primates and humans beginning in 1930s through 1950s and continuing to the present day in medical and evolutionary neuroscience. The research includes evidence from psychosurgery practices of the mid-century (leukotomy, lobotomy, etc.; e.g. see Fulton, 1952; Freeman & Watts, 1950)

The Model describes two archetypal neural circuitries from different periods of our evolution: The self-preserving circuitry from our early vertebrate heritage located anatomically in the brain stem (hindbrain, midbrain, and parts of the forebrain) and the other-preserving (affectional) circuitry located anatomically in the limbic system and related areas, primarily from our later mammalian heritage.

The essentially conflicting circuitries, interlocked in homeostatic regulation, are plugged into our higher brain centers (frontal cortex) by white matter axonal cabling that passes largely through a gating neural structure called the thalamus, with reciprocal connections to the higher cortex and archetypal motivating circuitries allowing their amplification or diminution. The CSN Model denotes that the impulses of these archetypal motivating circuitries are abstractly expressed as Ego and Empathy in the frontal cortex. Although it

2 represents a commonly perceived sad day in the history of psychiatry and neurosurgery, the connecting cables between those circuitries and the frontal brain centers were surgically lesioned in lobotomies and similar procedures, producing frequently a clinical deactivation or "flat effect" in motivation—that is, reduced or no Ego or Empathy. A significant fact referred to above and developed at length for the first time in Wilson and Cory's book is that these conflicting circuitries are homeostatically regulated like other critical physiological functions, e.g., temperature or blood pressure regulation.

The authors convincingly make the case that the homeostatic regulation of these archetypal neural circuitries, as they tug and pull against each other, tend toward optimal homeostasis or dynamic balance effectively constituting a socially-interactive or social exchange brain. Such optimal homeostasis or dynamic balance supports the age-old wisdom reflected in the Golden Rule and concepts, not only of exchange, but justice and morality. Deviation from homeostasis induces behavioral and social tension, inequality and injustice in social exchange. A formulaic equation is developed to mathematically represent this dynamic (see also Cory 2006ab).

The following parts of the book (Parts II-IV) cover comprehensively the genetics, anthropology, sociobiology, and evolutionary epidemiology of mood disorders, specifically focusing upon mania and depression or bipolar disorder. Because the limited purpose of this review is to provide physiological insight into the foundations of social exchange and economics, I will not comment in detail upon these latter sections of the work except to acknowledge their obvious scholarship and contribution to science.

In concluding this review, it is apparent, based upon the evidence, that dual motive theory rests upon a sound platform in neurophysiology. Further, it represents an important step toward what has come to be called "consilience"(Wilson, 1998), the linkage of the natural with the social sciences. Such linkage promises to open up new avenues for further research into the critical socio-economic problems that face the world today.

References

Cory, G. 2006a. "Physiology and Behavioral Economics." The Handbook of Contemporary Behavioral Economics. Ed. by M. Altman. ME Sharpe.

Cory, G. 2006b. "A Behavioral Model of the Dual Motive Approach to Behavioral Economics and Social Exchange." The Journal of Socio-Economics. V. 35. N.4: 592-612.

Cory, G. 2004. The Consilient Brain. Kluwer Academic/Plenum.

Cory, G. 1999. The Reciprocal Modular Brain in Economics and Politics. Plenum.

Cory, G. and Gardner, R. Eds. 2002. The Evolutionary Neuroethology of Paul MacLean. Greenwood/Praeger.

3 Freeman, W. and Watts, J. 1950. Psychosurgery in the Treatment of Mental Disorders and Intractable Pain. Norton.

Fulton, J. 1952. Frontal lobotomy and affective behavior. Norton.

Jamison, K. 1996. An Unquiet Mind. Vintage Books.

MacLean, P. 1990. The Triune Brain in Evolution. Plenum.

Panksepp, J. 2002. "The MacLean Legacy and Some Modern Trends in Emotion Research." The Evolutionary Neuroethology of Paul MacLean. Ed. by G. Cory and R. Gardner. Greenwood/Praeger.

Physiology and Behavior. 2003. "A Tribute to Paul MacLean: the Neurobiological Relevance of Social Behavior." Volume 79, Number 3.

Wilson, E. O. 1998. Consilience: The Unity of Knowledge. Knopf.