Experimental researches into the physiology of the human voice : a memoir / by John Bishop.

  • Bishop John, 1797-1873.
Date:
1836
Catalogue details

Licence: Public Domain Mark

Credit: Experimental researches into the physiology of the human voice : a memoir / by John Bishop. Source: Wellcome Collection.

Provider: This material has been provided by the Royal College of Physicians of Edinburgh. The original may be consulted at the Royal College of Physicians of Edinburgh.

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    !) two lateral pyramidal portions, united in most subjects by a distinct glandular medium. Its size varies in different indivi- duals, but is said to be larger in the female than in the male. It has generally been supposed by anatomists that this gland exerts some influence on the voice, but its true functions are unknown *. The exquisite sensibility of the larynx, its dependence on the will, as well as its muscular motions, are derived from the superior and recurrent laryngeal filaments of the pneumo-gas- tric nerves. The distribution of these nerves to the muscles which act on the glottis is a subject of anatomical controversy. Experiments made on them by Martinf, Professor Sue of Paris, Dr. HaightonJ, Cruikshanks, Scarpa, Arnemann, Ma- gendie, and others, have been attended with curious results. The description given of them by the latter however is opposed by Rudolphi, Andersch, Soemmerring, Meckel, Bellingeri and others. The truth is, that the superior and recurrent nerves anastomose in wiving filaments to some of those muscles which dilate, as well as to those which close the glottis. The action of these muscles may be briefly recapitulated as follows: The crico-aiytenoidei postici open the glottis. All the other muscles close it. The mytenoideus obliquus and aryt. transversus close the arytenoid cartilages posteriorly. The crico-aiytenoidei laterales and the tliyro-arytenoidei close them anteriorly. The thyro-aiytenoidei close the centre of the glottis, and with the crico-lhyroidei, regulate its tension, posi- tion, and vibrating length. The views here taken of the actions of these muscles differ from those entertained respecting them by anatomical authors in general. Not having found any two anatomists strictly agreeing on the subject, I have been induced to make numer- ous dissections to ascertain their functions in producing voice. The annexed figures were drawn by Mr. Henry Dayman, from these dissections. The actions assigned to the thyro-ary- tenoidei admit of most discussion. That these muscles relax the vocal ligaments, and at the same time close the glottis, may at first sight appear exceedingly doubtful; but all my attempts to close the glottis by the approximation of the ary- tenoid cartilages and the tension of the cricu-thyroidei muscles • It appears to me by no means impossible that the thyroid gland secretes a fluid transmitted by some invisible process which lubricates the vocal tube. The constant passage of air must render it requisite that it should be kept permanently moistened. f Edinburgh Essays. j Mem. of the Med. Soc. of London.