The conduction of such stimulation to parts removed some distance from the sense organ suggests paths of transmission comparable to those which transmit nervous impulses in animals.
The capability of reacting to stimuli, the result is stimulation (Verworn).
Prolonged or excessive stimulation invariably leads to depression or paralysis, the tissues becoming fatigued, and from this condition they may recover or they may not.
Small, stimulating doses, and repeated, are good, but stimulation can be more effectively produced by ammonia or strychnine.
On stimulation these cells part with their water, the lower side of the organ becomes flaccid and the weight of the leaf causes it to fall.
This modification is important, because it transfers the formative influence from the plastic substances to the protoplasm, suggesting that, the diverse constituents are produced (whether spontaneously or as the result of stimulation) as secretions by the protoplasm.
The action of aconitine on the circulation is due to an initial stimulation of the cardio-inhibitory centre in the medulla oblongata (at the root of the vagus nerves), and later to a directly toxic influence on the nerve-ganglia and muscular fibres of the heart itself.
Our starting-point in this, as in all departments of biological study, must be the biological unit, and it is to the alterations to which this is subject, under varying conditions of nutrition and stimulation, that the science of pathology must apply itself.
Local hypertrophy may also be due to stimulation resulting from friction or intermittent pressure, as one may see in the thickenings on the skin of the artisan's hands.
Response Of Tissues To Stimulation A stimulus may be defined as every change of the external agencies acting upon an organism; and if a stimulus come in contact with a body possessing the property of irritability, i.e.
Jalap is a typical hydragogue purgative, causing the excretion of more fluid than scammony, but producing less stimulation of the muscular wall of the bowel.
A similar stimulation of the non-striped muscle in the alimentary canal results in violent vomiting and purging, if a large dose has been taken.
The initial hastening is due to a stimulation of the vagus terminals in the lung, as it does not occur if these nerves are previously divided.
The initial action of digitalis is a stimulation of the cardiac terminals of the vagus nerves, so that the heart's action is slowed.
Thereafter follows the most important effect of the drug, which is a direct stimulation of the cardiac muscle.
Thus among the tongue movements evoked by stigmatic stimulation of the cortex undeviated protrusion or retraction of the organ is not found.
Patients in whom, for purposes of diagnosis, it has been electrically excited, describe, as the initial effect of the stimulation, tingling and obscure but locally-limited sensations, referred to the part whose muscles a moment later are thrown into co-ordinate activity.
The seeming want of reaction of so much of the cerebellar structure under artificial stimulation, and the complex relay system revealed in the histology of the cerebellum, suggest that the impressions are elaborate.
The action of atropine in dilating the pupil is also aided by a stimulation of the fibres from the sympathetic nervous system, which innervate the remaining muscle of the iris - the dilator pupillae.
Cult divides into two unequal parts, the stimulation of the religious emotions and the control of piety.
The end and result of primitive religion is, in a word, the consecration of life, the stimulation of the will to live and to do.
There are three chief possibilities: (a) that the antitoxin is a modification of the toxin; (b) that it is a substance normally present, but produced in excess under stimulation of the toxin; (c) that it is an entirely new product.
Verworn to depend upon stimulation to contraction or the reverse.
Irritability, again, although a notable quality of living substance, is not peculiar to it, for many inorganic substances respond to external stimulation by definite changes.
After absorption it slows the pulse by stimulation of the vagus nerves.
Here he stated the principle, not before recognized, that the kind of sensation following stimulation of a sensory nerve does not depend on the mode of stimulation but upon the nature of the sense-organ.
Thus light, pressure, or mechanical stimulation acting on the retina and optic nerve invariably produces luminous impressions.
Under normal conditions the insect will live for three, four or sometimes five years, but the stimulation given, together with I FIG.
It is certain in any case that the process was constantly repeated &t different dates and in different parts of the country from Aswan to Axum, and to the stimulation which resulted from it must be ascribed the principal political and intellectual movements of the Sudanese nations.
With some of them, such as chloral and chloroform, the stimulation period is short compared with the narcotic period, while with others, such as ether, the reverse is the case.
In the weeks of natural stimulation, she had been the one who was embarrassed.
In both these cases the stimulation is followed, not only by movement, but by the secretion of an acid liquid containing a digestive juice, by virtue of which the insect is digested after being killed.
What the nature of the stimulation is we are not able to say.
The stimulation of the liver is said to depend upon the solution of the resin by the intestinal secretion.
He was hungry after the stimulation of Jessi's refusal to bend to his will.