9) The Neurophysiological Hypothesis
This is derived from the Papez-MacLean theory of emotions. Dr Paul Maclean was the head of the laboratory of Brain Evolution and Behaviour, Maryland, USA. It is a good start if you are on a road to your own personal discovery of who and what you are. It is quite simple.
This theory is based on the differences in anatomy and function between the archaic structures of the brain shared by men with the reptiles and lower mammals, and the ‘specifically’ human neocortex, which evolution superimposed on them.
10) The result of this evolutionary blunder is an uneasy coexistence, frequently erupting in acute conflict, between the deep ancestral structures of the brain, mainly concerned with instinctive and emotional behaviour, and the neocortex, which endowed man with language, logic, and symbolic thought.
11) MacLean writes, "Man finds himself in the predicament that nature has endowed him essentially with three brains, which despite great differences in structure, must function together and communicate with one another.
a) The oldest of these brains is basically reptilian.
b) The second, has been inherited from the lower mammals, and the
c) third, is a late mammalian development, which has made man, peculiarly man, "While the antediluvian structures of the very core of our brain, which control instincts, passions and biological drives, have hardly been touched by evolution, the neocortex of the hominids expanded in the last half-a-million years at an explosive speed which is without precedent in the history of evolution, so much so that some anatomists compared it to a tumorous growth. But explosions do not produce harmonious results".
12) The result in our case seems to have been that the rapidly developed thinking cap, which endowed man with his reasoning powers, did not become properly integrated and co-ordinated with the ancient emotion bound structures on which it was superimposed with such unprecedented speed. The neural pathways connecting the neocortex with the archaic structures of the mid-brain are apparently inadequate.
13) Thus the brain explosion gave rise to a mentally unbalanced species, in which the old brain and the new brain, emotion and intellect, faith and reason, were at loggerheads. On the one side, the pale cast of rational thought of logic, suspended on a thin thread all to easily broken, on the other, the native fury of passionately held irrational beliefs, reflected in the holocausts of past and present history.
14) If neurophysiological evidence had not taught us to the contrary, we would of have expected it to reveal an evolutionary process that gradually transformed the primitive old brain into a more sophisticated instrument, as it transformed gill into lung, or the forelimb of the reptilian ancestor into the bird’s wing, the flipper of the whale, and the hand of man.
15) But instead of transforming old brain into new, evolution super-imposed a new superior structure on an old one, with partly overlapping functions and without providing the new brain with the clear-cut power of control over the old. MacLean has coined the term "schizophysiology" for this shortcoming in the nervous system.
16) The hypothesis that this type of "schizophysiology" is part of our genetic inheritance, built into the species, as it were, could go a long way towards explaining some of the pathological symptoms already listed. The chronic conflict between rational thought and irrational beliefs, the resulting paranoid streak in our history, the growth curves of science and ethics, would at last become comprehensible and could be expressed in physiological terms.
And any condition that can be expressed in physiological terms should ultimately be accessible to remedies!
Note 7. The Psychological Hypothesis – to follow.