Observations on the ganglionic enlargement of the pneumo-gastric nerve; the probable function of that ganglion; and the position which it occupies in the human subject and in several of the lower animals / [Edward Cock].

  • Cock, Edward, 1805-1892.
Date:
1837]
Catalogue details

Licence: Public Domain Mark

Credit: Observations on the ganglionic enlargement of the pneumo-gastric nerve; the probable function of that ganglion; and the position which it occupies in the human subject and in several of the lower animals / [Edward Cock]. Source: Wellcome Collection.

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    The dissections which I have made on various animals all tend to confirm the accuracy of the opinion entertained by Sir Astley Cooper respecting the nature and function of this ganglion ; viz. that it forms one of that class of ganglia which appear to be necessary appendages to all nerves of common sensation; and that it belonofs more particularly to the superior laryngeal nerve, which indeed is the only branch of the par vagum which we can positively identify as exercising a purely sensitive function f. The exclusive in its signification, as restricting the use of the ganglion to that nerve alone ; whereas, from the dissections I have made, I have every reason to believe that the ganglion does not belong exclusively to the la¬ ryngeal branch, but extends its influence to numerous other filaments included in the trunk of the par vagum, and affording to the lungs, to the pharynx, oesophagus, and stomach, that faint but peculiar sensibility which they appear to possess—filaments which impart to the stomach the sensation of fulness when that organ has been distended with food ; to the lungs, the besoin de respirer,” and the sensory functions necessary for respiration alluded to by Bichat. In the sheep, where I was enabled to unravel the fibres of which the par vagum is composed, and trace with considerable accuracy their course and their connexion with the ganglion, I found the following arrangements to existThe pneumo-gastric trunk, as it left the base of the scull, might be said to consist of two orders or sets of fila¬ ments ; viz. the ganglionic, and the ganglionless. The former terminated in the ganglion, where their fibrous character became lost after the manner of the posterior roots of the spinal nerves: the latter were con¬ tinued downwards beyond the ganglion, having merely a cellular connexion with it, and resembled in this respect the motor portion of the fifth pair. Lastly, from the ganglion arose two sets of nerves : the one constituted the laryngeal; the other joined the ganglionless filaments mentioned above, and formed part of the trunk of the par vagum, descending to the chest. A careful dissection will bring to light a similar arrangement in the human subject, the horse, the ass, and probably in other animals. (Vide Diagrams 7*) I may also observe, that the laryngeal nerve appeared to derive some very minute fibrillae fi’om the pneumo-gastric trunk above the gan¬ glion. These might be either specific respiratory filaments, or motor-mus¬ cular filaments, perhaps both. *|- The resemblance between the ganglia on the posterior roots of the spinal nerves and the pneumo-gastric ganglion did not escape the obser¬ vation of Meckel. He seems, indeed, to have considered the pneumo-gastric, glosso-pharyngeal, and accessory nerves as all derived from the posterior spinal columns; and thus constituting a posterior root, which, on its exit from the cranium, is joined by the lingual nerve from the anterior columns ; the combination of the four nerves thus forming a trunk, which, in its origin, composition, and function, is analogous to a spinal nerve. This view of the subject can, I think, hardly be maintained; as it is much more in accordance