Now, as a fact this theoretical possibility is just what happens. It is one of the commonest of occurrences, although it is too frequently misunderstood.[218] A person, we will say, has acquired—owing to no matter what psychogenetic factor—a recurrent fear. This fear, or, in less obtrusive form, anxiety, or apprehension, is, we will say, of disease—heart disease or insanity or fainting or cancer or epilepsy or what not. It recurs from time to time when awakened by some thought or stimulus from the environment. At once there is an outburst of physiological, i.e., functional disturbances, in the form of an “attack.” There may be violent cardiac and respiratory disease, tremor, flushing, perspiration, diarrhœa, sensory disturbances, etc., followed by more or less lasting exhaustion. On the principle of complex building, which we have discussed in a previous lecture, the various physiological reactions embraced in such a scheme as I have outlined tend to become welded into a complex (or association psycho-neurosis), and this complex of reactions in consequence recurs as a syndrome every time the fear is reëxcited. On every occasion when the anxiety recurs, a group of symptoms recurs which is made up of these physical manifestations of emotion which are peculiar to the individual case. The symptoms, unless a searching inquiry is made into their mode of onset, sequence, and associative relations, will appear a chaotic mass of unrelated phenomena; or only certain obtrusive ones, which in the mind of the patient point to disease of a particular organ, are described by him. The remainder have to be specifically sought for by the investigator. The latter, if experienced in such psycho-neuroses, can often from his knowledge of the phenomena of emotion anticipate the facts and in a large degree foretell to the patient the list of symptoms from which he suffers. By those who lack familiarity with these functional disturbances mistakes in diagnosis are frequently made. Disease of the heart, or of the stomach, or of the nervous system is frequently diagnosed when the symptoms are simply the product of emotion. Quite commonly, when the symptoms are less related to particular organs, but more conspicuously embrace vasomotor, sensory, digestive disturbances (inhibition of function), and fatigue, the syndrome is mistaken for so-called _neurasthenia_.[219] Thus it happens that in recurrent morbid fears—known as the phobias or obsessions—a group of symptoms are met with which at first sight appear to be unrelated bodily disturbances, but which when analyzed are seen to be only a certain number of physiological manifestations of emotion welded into a complex. On every occasion that the fear recurs this complex is reproduced. It now remains to study the effect of the emotions on the psychical side. This we shall do in the next lecture. ----- Footnote 196: