. Electro-physiology . FIG. 2-20. there is an opening g in the horizontal arm of the cylinder, which Pfliiger conceives to be spiriform, its highest point lying next the piston. If the elasticity of the spring is increased, it presses more strongly upon the piston, pushes it farther from the opening g, and displaces the fluid in front of it, which then rises higher in the vertical limb, and there is in- creased hydrostatic pressure. If, on the other hand, the elasticity of the spring is diminished, the fluid displaces the piston in the opposite direction cd, and pushes it more or less away fro
. Electro-physiology . FIG. 2-20. there is an opening g in the horizontal arm of the cylinder, which Pfliiger conceives to be spiriform, its highest point lying next the piston. If the elasticity of the spring is increased, it presses more strongly upon the piston, pushes it farther from the opening g, and displaces the fluid in front of it, which then rises higher in the vertical limb, and there is in- creased hydrostatic pressure. If, on the other hand, the elasticity of the spring is diminished, the fluid displaces the piston in the opposite direction cd, and pushes it more or less away from the opening g, which is then reached by the fluid, which, on streaming out, acquires vital energy deriving from the height of fall. With this streaming out, the hydrostatic pressure diminishes, so that the force of the spring gradually pushes the piston back again over the opening and ends the discharge. We have next to see how this schematic mechanism explains the reaction of the living transverse section of the nerve with respect to excitation, conductivity, and excitability, and, in the first place, the phenomena and laws of electrotonus. This explanation follows simply from the following hypothetical premiss as set out by Pfliiger. The electrical current flowing through a portion of the nerve alters the force of molecular inhibition, and this alone, in a direct sense, with no immediate modification of potential energy. The effect of current on the inhibitory force is to increase it in the region of anelectrotonus, and diminish it in that of katelectro- tonus, the elastic force of the piston-spring increases in all sections of the cylinder, which represent anelectrotonised sections of the nerve, and decreases in those that are katelectro- tonised. Further, in the anelectrotonic region the inhibitory force, the piston D, is displaced in the direction of the arrow ab, whereby the potential energy, the height of the column of fluid at BO, increases, while in th
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Keywords: ., bo, bookcentury1800, bookdecade1890, bookpublisherlondonmacmillan
