For many years investigations of the hypnoidal state were carried out by me on subjects and patients, adults, and children. The work was entirely limited to the study of such states as found in man. Having found that during the hypnoidal state the condition of suggestibility is quite pronounced for therapeutic purposes, and having effected many cures of severe psychopathic maladies ranging throughout the whole domain of hysterical affections, neurasthenia, obsessions, drug habits, especially alcoholic ones, the hypnoidal state has become, in my practice, quite an important therapeutic agent. Other investigators have obtained some excellent results with the hypnoidal state in their treatment of various functional, psychopathic maladies.
Thus far, the work with the hypnoidal state has been confined entirely to observations and experiments on human subjects and patients, and also to the treatment of man’s psychopathic ailments. I undertook a series of experiments on sleep, both from a phylogenetic and ontogenetic standpoint, following up the conditions and manifestations of sleep in the ascending scale of animal life, from the frog and the guinea pig, through the cat, the dog, to the infant and the adult.
My experiments clearly prove that the hypnoidal state is by no means confined to man, but is also present in animals. This is important since it indubitably shows how widely spread the hypnoidal state is throughout the domain of animal life. Moreover, the experiments clearly prove that the further down we descend in the scale of animal organization, the more prominent, the more essential, does the hypnoidal state become.
The conclusion is forced upon me that the hypnoidal state is the primitive rest-state out of which sleep has arisen in the later stages of evolution. We may say that sleep and hypnosis take their origin in the hypnoidal state.[8] Sleep and hypnosis are highly differentiated states; they have evolved out of the primitive, undifferentiated, hypnoidal state which is essentially a subwaking rest-state characteristic of early and lowly-organized animal life. The hypnoidal state is the primordial sleep state.
The development of the hypnoidal state into sleep has proven itself useful in the struggle for existence of the higher animals; it has, therefore, become fixed as the rest-state, characteristic of the higher representatives of animal life. Hypnosis and other trance-states, variations of the primitive hypnoidal rest-state, have become eliminated as useless and possibly harmful to the normal life adjustments of the higher animals and can only be induced under artificial conditions in but a fraction of the human race.
The hypnoidal state is the normal rest-state of the lower vertebrates and invertebrates. The rest or sleep state of the lower animals is a sort of passive waking state,—a subwaking state which has survived in man as the hypnoidal state. Of course, the state has been largely modified in man by the course of evolution, but it can still be clearly detected, just as the tail of the simian can be discerned in the human coccyx, or as the structure of the prehensile hand of the quadrumana can be still clearly traced in the foot of man. Waking, hypnoidal, and sleep-states may be termed normal states, while hypnosis and various other trance-states may be termed sub-normal states.
The relation of the hypnoidal state to waking, sleep, hypnosis, and other subconscious states may be represented by the diagram on [following page.]
The hypnoidal state is normal, it is present in all representatives of animal life.
Sleep, hypnosis, and trance-states are variations of the fundamental hypnoidal state. The sleep-state has proven useful and has become normal in the higher animals, while hypnosis like animal “cataplexy” and the various forms of trance-states, likewise variations of the fundamental hypnoidal state, characteristic of man, have not proven of vital value, and have fallen below the normal stream of consciousness with its concomitant adaptive reactions.