The Neural Energy Constant: A Study of the Bases of Consciousness.

This unpretentious little book is well worth the perusal of physicians who are interested in the study of human behavior. The author is conservative, stating frankly that he presents only an hypothesis, but one which seems to offer a basis of explanation for many facts of clinical observation. Briefly, he suggests that consciousness is evolved from a primitive awareness that is a property of living cells by the development of, first, a center of awareness, possibly hypothalamic in location, second, an emotional level or level of "coarse adjustment," probably situated in the optic thalamus, and, third, a level of the "fine adjustment" consisting of the memory and associative systems of the cerebral cortex. Full consciousness occurs only when the three levels are "in correct functional apposition." Fatigability of nerve cells requires economy in their use and determines the limitations of momentary consciousness and results in the establishment of a limited