Neurologic progress and prospects : chairman's address, delivered before the Section on Nervous and Mental Diseases of the American Medical Association, at the Fifty-fourth Annual Session, held at New Orleans, May 5-8, 1903 / F.W. Langdon.

  • Langdon, Frank Warren, 1852-1933.
Date:
1903
Catalogue details

Licence: In copyright

Credit: Neurologic progress and prospects : chairman's address, delivered before the Section on Nervous and Mental Diseases of the American Medical Association, at the Fifty-fourth Annual Session, held at New Orleans, May 5-8, 1903 / F.W. Langdon. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

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    published some six years ago, were claimed by him to show that the entire nervous system is permeated by a network of ultimate fibrillae passing unbroken through the neurons. They have been in part accepted by Bethe and Nissl, who also consider that the resulting “fibril- lary hypothesis” invalidates the neuron doctrine. As these fibrillae themselves, according to Apathy’s showing, are a product of certain neuron bodies (cells), the con- clusion that they are of secondary importance only seems justified at present. Far from disproving or supplanting the neuron doc- trine the “fibrillary hypothesis” of Apathy seems to the writer to have merely attained the dignity of an ap- pendage to it; an appendage, doubtless of considerable import, it is true, but just how important remains to be determined by its verification in a larger series of or- ganisms than earthworms and leeches. NEURODYNAMICS. The nature of nerve force and the conditions of its transmission yet remain an unopened book, of which Professor Loeb8 has essayed to exhibit to us the title page in his ingenious application of the electro-chemical theory of ions to the dynamic processes of the neuron and muscle cell. The main landmarks of his hypothesis may be briefly stated as follows: 1. An ion is the electrolytic representative of an atom, but is, theoretically, much smaller in size. 2. Ions, like the electrolytes of which they are the ultimate electrical units, are positive or negative, hence anions and kations. 3. Their function, by their presence in definite pro- portion in each tissue, is to preserve the “labile equi- librium” of the colloid materials of protoplasm on which its activities depend. 4. Variations in these proportions or attempts to re- store the same to normal (through electro-chemical action) give rise to function in the particular tissue that is the seat of such variation at any given time. 5. Hence, the dynamic process of neurons, as of muscle cells, may depend on the proportions of ions of, say calcium, sodium, potassium, etc., that are present at any particular instant. 6. This, if verified, would apparently indicate that the dynamics of function reside in the ions, while the