She grew daily more exhausted, and the weakness in her legs increased until a hysterical paraplegia of both legs declared itself. Nacke insists on the legal significance of dreams. Hysterical girls have often declared that they had been raped although they had only dreamed it; and in a similar way chronic drunkards have been led to accuse themselves or others of murder. According to Nacke, whenever a hysterical or neurasthenical or otherwise nervous person, or more particularly a drunkard, makes a definite statement we must invariably be on our guard, and bear in mind that there is always the possibility of a night-dream being continued in waking life. Nacke adds that Schmitt refers the acts of pyromaniacs to their dreams. To dream of fire has such an influence on them that they feel compelled to set fire to something when they are awake. Nacke, however, doubts whether this view is justified. In other cases the connection between a dream and the subsequent phenomena of waking life is different, and the phenomena could only be erroneously attributed to the dream. We shall see that there are pathological phenomena which are more readily perceived in dreams than in the waking state. I shall return to this point later on.

Occasionally, there is a connection between the phenomena of waking life and dreams, but it has nothing to do with the phenomena described above. A young lady tells me that she is always in a bad temper in the morning if she has been awakened in the middle of a pleasant dream. The interruption makes her irritable.

Post-hypnotic suggestion finds a special analogy in those dreams which influence the first appearance of mental disease. Trenaunay has pointed out this connection in his work Le Reve prolongs. Like Klippel, he calls attention to the case in which the dream is continued in waking life and there causes delirium by disturbing the normal course of ideas. Onirismus is the name given by Regis to those states in which a person is the victim of a prolonged dream. When onirism occurs at night the symptoms are disturbed sleep, nightmare, delusions of the senses - especially of vision - excitement, delirium. As a rule these phenomena disappear when the patient wakes, but in severe cases of onirism they continue after waking. Long ago, moreover, alienists were struck by the connection between dreams and mental disease. Griesinger relates cases of delirium which began in dream and did not show itself in waking life till later on; and in acute mania it has been observed (Esquirol) that the patient thinks he has been ordered in a dream to do something which afterwards he actually does.

Hohn-baum reports that the first outbreak of mania often dates from a horrible and alarming dream, and that the predominant idea is connected with that dream (Freud). Of course, it is explicable that in many such cases the dream was but a symptom of the disease; nevertheless, Sante de Sanctis has in recent times directed his attention chiefly to the question whether the dream might not be the cause of the mental disorder. He points out that Baillarger has observed cases of delirium arising from hypnagogic hallucinations, and that statements to the same effect have been made by Brierre de Boismont, Maury, Falret, and others. The Salpetriere school, also, has adduced many facts which help to explain the connection between dreams and the delirium of an attack of hysteria. Chaslin, too, cites cases from his own experience and from the literature of the subject, and concludes that although it is true that every case of delirium does not originate in a dream, and is not necessarily influenced by one, yet such cases occur much more frequently than we think.

As the result of his own experience and a careful study of the material to hand, Sanctis has come to the conclusion that dreams and mental disorder are very closely connected etiologically. An exciting dream may so perturb the mind of a predisposed individual that he will appear distracted for a time, or a dream may set up a case of melancholia or a phase of alternating (circular) insanity. According to Guislain, a maniacal condition may have its inception in a dream, and an insane idea or visual hallucination be developed unconsciously from dream-life or the hypnagogic period. Something dreamed may be held to be an experience of waking life and thus become the origin of the preponderating idea in megalomania, persecutory mania, or religious mania. It seems certain that more than one psychopathic state can be called up by dreams.

In discussing the manner in which dreams induce mental disorders Sanctis distinguishes two cases. In the first a dream may act like a mental trauma. Here the mental disturbance which ensues is to be counted a traumatic neurosis or psychosis, or a state of exhaustion. We must bear in mind with Fere that even if the dream-images are false, the dream-feelings are true, and that the physical changes wrought by a dream are so great that a dreamer may be very powerfully influenced by them. The consequences of the excitement thus produced may easily persist in the subsequent waking state, even when the feeling itself has disappeared. Toulouse, consequently, likens the way in which a mental disorder follows a dream to a powerful agitation. Sometimes, according to Sanctis, it is the cerebral exhaustion caused by a dream, and not the excitement during the dream, which is the etiological moment in producing mental disturbance in waking life. According to Sanctis, the second way in which dreams may produce mental disturbance extends over a much greater area.

These are the cases in which the waking consciousness takes over the "dream-stuff." It is not necessary that the morbid state should immediately follow the dream; there may be an interval of greater or lesser duration, though in other cases dream-images may be continued into the waking state, just as we have seen happen in continuative post-hypnotic suggestions. Such cases have been described by Tissie, Manaceine, Maury, Brierre de Boismont, Baillarger, and others. Cases in which a definite belief is acquired during a dream bear even a greater resemblance to post-hypnotic suggestion. Although the condition produced is as a rule only a passing one, it sometimes happens that the "belief" induced takes root in the waking state and leads to acts corresponding to its nature.