The descriptive and physiological anatomy of the brain, spinal cord, and ganglions, and of their coverings : Adapted for the use of students.

  • Todd, Robert Bentley, 1809-1860.
Date:
1845
Catalogue details

Licence: Public Domain Mark

Credit: The descriptive and physiological anatomy of the brain, spinal cord, and ganglions, and of their coverings : Adapted for the use of students. Source: Wellcome Collection.

Provider: This material has been provided by the University of Massachusetts Medical School, Lamar Soutter Library, through the Medical Heritage Library. The original may be consulted at the Lamar Soutter Library at the University of Massachusetts Medical School.

    15/308
    which is perceived by the mind. A physical change in the course of the fibres of the nerve, or at their central extremity, may give rise to a sensation similar to that ordinarily produced by an impression at the periphery. Or the mind may excite a portion of the centre of sensation, so as to occasion a feeling, of precisely the same nature as that, which usually results from an external cause. 11.—The fibres of nerves remain distinct, but in juxta-position, from centre to periphery; no anastomosis takes place between them. An inter- change of fibres does occur, however, between neighbouring trunks of nerves, by means of which different portions of the nervous centres are brought into connection with each other, and with an extended peripheral surface. 12.—The nervous force is a polar force, resem- bling electricity in the instantaneousness of its development and in the rapidity of its propagation, but differing from it in several important features. 13.—It is a peculiar feature of the nervous force, not only that it may be developed under the influence either of a mental or of a physical stimulus; but that, being excited by a physical stimulus, it is capable of affecting the mind. 14.—Hence nervous actions may be conveniently distinguished into two classes, according as the