. Anatomy, descriptive and applied. Anatomy. 818 THE NEB VE SYSTEM The Neurone Doctrine.—The results of the investigations of Golgi, Cajal, Forel, and others prompted Waldeyer to enunciate a theory with regard to the nerve mechanism of the neurone. This hypothesis is generally known as the neurone theory and assumes that (1) each neurone is a distinct and separate entity; (2) the collaterals and other terminals of the neurone form no connections among themselves; (3) neurones are associated, and impulses conveyed, by contact or contiguity of the axonic terminals of one axone with the cell body
. Anatomy, descriptive and applied. Anatomy. 818 THE NEB VE SYSTEM The Neurone Doctrine.—The results of the investigations of Golgi, Cajal, Forel, and others prompted Waldeyer to enunciate a theory with regard to the nerve mechanism of the neurone. This hypothesis is generally known as the neurone theory and assumes that (1) each neurone is a distinct and separate entity; (2) the collaterals and other terminals of the neurone form no connections among themselves; (3) neurones are associated, and impulses conveyed, by contact or contiguity of the axonic terminals of one axone with the cell body or dendrites of another neurone. The theory postulates a nerve cell amebism analogous to the extension and retraction of the pseudopodia of an ameba, and the "retraction theory" has been propounded in explanation of certain functional dissociation phenomena attending nerve force manifestations. ?Nerve Organ of Golgi, showing Tendon bundles, ramification of nerve fibrils. Muscle fibres. Fig. 593.—Neurotendinous spindle organ of Golgi from the human tendo calcaneus (Achillis). (After Ciaccio.) Opposed to the "neurone theory" or "contact theory" is the more recent continuity theory which is being earnestly advocated by Apathy, Bethe, and Nissl. In behalf of this theory it is claimed that the neurofibrils are continuous not only within the cell and its processes, but through an extracellular network as well. The dispute now being waged does not, however, affect our funda- mental ideas regarding the individuality of neurones with regard to their dynamic condition. The Supporting Tissue Elements of the Nerve System.—A fine meshwork of non-neural tissue, more or less dense in different localities, but apparently restricted to the central axis, serves to support the neurones. This sustentacular tissue is of two kinds: (1) the neuroglia; (2). connective-tissue trabeculse derived from (a) the pia or (b) vascular channels. The Neuroglia.—The
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectanatomy, bookyear1913
