A concussion is a shaking, a jarring, an agitation, or a shock caused by a collision. The real and direct cause of disease is more or less nerve tension than normal. Displaced bones because of their pressure against, or non-resistance of nerves, or that of stretching, cause an extra or a lessened amount of tension. An abnormal performance of function of the body is denominated disease, the kind depends upon the tissue affected and the function disturbed. The subtile and nicely discriminating transmission of physiological impulses, in health, whether of cells, the elementary structure of which organic substances are formed, individual organs, or the body as an organism, is directed by an intelligence known as spirit.
Sensation is the recognizance of nerve vibration.
Sensory nerve centers is where nerve vibration is identified. A sensory nerve is an efferent nerve, one which transfers peripheral impressions to the sensoria, sense-centers. Sensory ganglia are those masses of nervous substance which are thought to serve as a center of nervous influence. The most prominent of the sensory nerves are those of the olfactory, optic, auditory, gustatory, tactile and thermal. To these should be added that of cenesthesia, conscious existence, painful or pleasurable, depression or exaltation, the general sense of bodily, or self-existence, the subconscious sensation by the functioning of the internal organs.