ORGANIC NERVOUS DISEASES IN RELATION TO BEHAVIOR
Physiologists and psychologists have long known that it is the nervous system which makes integrated behavior possible, and that a sound nervous system is a prerequisite for the proper functioning of the entire human being. Thus, a healthy nervous system is essential to the normal operation of the vegetative processes, such as digestion, respiration, circulation, and excretion; the sensory-motor processes (sensation and movement); and the so-called "higher" or "mental" processes, such as thinking, intelligent action, adjustment to the social environment, and the like. For this reason disturbances in the functioning of the nervous system may cause serious abnormalities in behavior.
Injury or disease of the vegetative (i.e., the autonomic) nervous system may be revealed in various kinds of malfunctioning, mainly of the viscera, which manifest themselves in numerous disorders of the glandular, vascular, respiratory, genitourinary, and gastrointestinal systems. Sensory-motor disturbances derive from disorders of the cranial and peripheral nerves, the spinal cord, the brain stem (i.e., medulla, pons, midbrain, basal ganglia), the cerebellum, and the cerebrum. Such disorders are revealed in sensory disturbances and in disturbances in the integrated and balanced action of the various motor organs of the body. Personality disorders and disturbances in memory, sequential thinking, social adjustments, and the like are associated primarily with the malfunctioning of higher brain centers, in particular, of the cerebral cortex, whether this malfunctioning be due to disease, injury, or some other cause.
The initial problem of the neurologist is to determine the locus and nature of the disturbance in the nervous system. This diagnosis is based upon the concrete behavior abnormalities (i.e., the symptoms) which he observes in the individual patient. After the diagnosis has