Internal Organic Somatic Stimuli
Since we are now engaged in looking for sources of dreams inside the organism instead of outside it, we must bear in mind that almost all our internal organs, though they give us scarcely any news of their working so long as they are in a healthy state, become a source of what are mainly distressing sensations when they are in what we describe as states of excitation, or during illness. These sensations must be equated with the sensory or painful stimuli reaching us from the outside.
During sleep the mind attains a far deeper and wider sensory consciousness of somatic events than during the waking state. It is obliged to receive and be affected by impressions of stimuli from parts of the body and from changes in the body of which it knows nothing when awake. Beginnings of an illness might make themselves felt in dreams before anything could be noticed of it in waking life, owing to the magnifying effect produced upon impressions by dreams. Medical writers too, who were certainly far from believing in the prophetic power of dreams, have not disputed their significance as premonitors of illness.
Instances of the diagnostic power of dreams seem to be vouched for in more recent times. The story of a forty-three-year-old woman, who, while apparently in perfect health, was for some years tormented by anxiety-dreams. She was then medically examined and found to be in the early stages of an affection of the heart, to which she eventually succumbed.
Thus, the dreams of those suffering from diseases of the heart are usually short and come to a terrifying end at the moment of waking, their content almost always includes a situation involving a horrible death. Sufferers from diseases of the lungs dream of suffocation, crowding and fleeing, and are remarkably subject to the familiar nightmare. In the case of digestive disorders dreams contain ideas connected with enjoyment of food or disgust. Finally, the influence of sexual excitement on the content of dreams can be adequately appreciated by everyone from his own experience and provides the theory that dreams are instigated by organic stimuli with its most powerful support.
While we are awake we are aware of a diffuse general sensibility of coenaes-thesia, but only as a vague quality of our mood, to this feeling, according to medical opinion, all the organic systems contribute a share. At night however, it would seem that this same feeling, grown into a powerful influence and acting through its various components, becomes the strongest and at the same time the commonest source for instigating dream-images. If this is so, it would only remain to investigate the laws according to which the organic stimuli turn into dream-images.
We have here reached the theory of the origin of dreams which is preferred by all the medical authorities. The line of thought which regards vegetative organic sensation as the constructor of dreams has, moreover, a particular attraction for medical men since it allows a single aetiology for dreams and mental diseases, whose manifestations have so much in common, for coenaesthetic changes and stimuli arising from the internal organs are also held largely responsible for the origin of the psychoses. It is not surprising, therefore, that the origin of the theory of somatic stimulation may be traced back to more than one independent source.
During the day time the stimuli from the interior of the organism, from the sympathetic nervous system, exercise at the most an unconscious effect upon our mood. But at night, when we are no longer deafened by the impressions of the day, those which arise from within are able to attract attention, just as at night we can hear the murmuring of a brook which is drowned by daytime noises.
The influence of organic somatic stimuli upon the formation of dreams is almost universally accepted today, but the question of the laws that govern the relation between them is answered in very various ways, and often by obscure pronouncements. On the basis of the theory of somatic stimulation, dram-interpretation is thus faced with the special problem of tracing back the content of a dream to the organic stimuli which caused it.
There is a fair amount of agreement, however, over the interpretation of various forms of dreams that are described as "Typical", because they occur in large numbers of people and with very similar content. Such are the familiar dreams of falling from a height, of teeth falling out, of flying and of embarrassment at being naked or insufficiently clad. This last dream is attributed simply to the sleeper's perceiving that he has thrown off his bedclothes in his sleep and is lying exposed to the air. The dream of teeth falling out is traced back to a "Dental Stimulus", though this does not necessarily imply that the excitation of the teeth is a pathological one.
The flying dream is the image which is found appropriate by the mind as an interpretation of the stimulus produced by the rising and sinking of the lobes of the lungs at times when cutaneous sensations in the thorax have ceased to be conscious, it is this latter circumstance that leads to the feeling which is attached to the idea of floating.The dream of falling from a height is said to be due to an arm falling away from the body or a flexed knee being suddenly extended at a time when the sense of cutaneous pressure is beginning to be no longer conscious, the movements in question cause the tactile sensations to become conscious once more, and the transition to consciousness is represented physically by the dream of falling.
Another rule lays it down that if during sleep an organ is in a state of activity, excitation or disturbance, the dream will produce image related to the performance of the function which is discharged by the organ concerned. These are the findings as follows:-
(1) The position of a limb in the dream corresponds approximately to its position in reality. Thus, we dream of the limb being in a static condition when it is so actually.
(2) If we dream of a limb moving, then one of the positions passed through in the course of completing the movement invariably corresponds to the limb's actual position.
(3) The position of the dreamer's own limb may be ascribed in the dream to some other person.
(4) The dream may be of the movement in question being hindered.
(5) The limb which is in the position in question may appear in the dream as an animal or monster, in which case a certain analogy is established between them.
(6) The position of a limb may give rise in the dream to thoughts which have some connection with the limb. Thus, if the fingers are concerned, we dream of numbers.