Mechanism in Nerve Centres

Abstract

MACCURDY, in his stimulating book, “Common Principles in Psychology and Physiology”, has assailed the mechanistic interpretation of reflex function as incompatible with known facts. He concedes that the nerve impulse, as exhibited in the peripheral nerve fibre, may be explicable on a physical basis, but he insists that as soon as we encounter the function of the nerve centre, even as exemplified in the simplest reflex arc, we are forced to recognise the presence of something quite apart from any physical mechanism. He contends that the nerve centre does not merely conduct impulses (as does the nerve fibre) but produces them. MacCurdy further objects to the assumption of physical mechanism in the nerve centre on three specific grounds; namely, a machine “cannot change itself or its functions to meet new conditions; it does not improve its performance with practice; it cannot perform some particular function depending originally on one part, after that part is destroyed”.