Neurology

Abstract

MANY theories of inhibition are here collected and reviewed, but the majority have to be rejected at once in the light of present-day knowledge. From the examination of the data the 'humoral' theory is regarded as far above the others. This theory has previously been discussed in relation to the spinal reflexes but is discussed here in view of its wider implications. It is shown that this theory offers a satisfactory explanation of some difficulties in the concept of 'physiological levels' and gives a solution of the problem of 'back-control' between levels. The law of forward direction is found to follow at once from this theory, and various microscopical morphological appearances are shown to be just the type of mechanism required by it. Also Pavlov's 'irradiation' and 'concentration' are thus easily explained. Integration in behaviour is compared with the same process in growth, and it is suggested that the ultimate mechanisms are probably identical. Some of the factors known to be of importance in growth are considered, and it is shown that the 'humoral' theory provides the counterpart in behaviour. The clinical applications are discussed. C. S. R.