Hallucinations exercise an influence upon the general psychic condition of the patient, which varies with the subject, the nature of the disease, and the different stages of the same disease.

In a general way it may be stated that the more acute the character of the mental disorder (acute psychoses, periods of exacerbation in chronic psychoses) and the less enfeebled the intellectual activity, the more marked is the influence of the hallucinations. In accordance with this rule, the correctness of which is clinically demonstrated, hallucinations abate in their influence as the acute stage of the psychosis subsides - either when the patient enters upon convalescence, or when he lapses into dementia; under such conditions they may persist for a greater or lesser length of time without exercising any influence upon the patient's emotions or actions.

Influence Of Hallucinations Upon The Psychic Functions. Attention

Hallucinations force themselves upon the attention of the patient. In the case of hallucinations of hearing, for instance, he is compelled to listen to them, sometimes in spite of himself, no matter what their degree of clearness is - whether they consist of distinctly spoken words or phrases, or of a scarcely perceptible murmur.

The patient is sometimes conscious of the tyrannical dominating power to which he is subjected. "I am forced to listen to them," said one of these unfortunates; "when they (his persecutors) get at me I can do no work, cannot follow any conversation, I am wholly in their power." Hallucinations thus resemble imperative ideas and autochthonous ideas which we shall study later on.


Hallucinations may coexist with sound judgment and be recognized by the patient as a pathological phenomenon. They are then called conscious hallucinations. Such instances are not very rare and consist chiefly of hallucinations of sight. A celebrated case is that of Nicolai, the bookseller. " The visions began in 1791, after an omission of a bloodletting and an application of leeches which he underwent habitually for hemorrhoids. All of a sudden, following a strong emotion, he saw before him the form of a dead person, and on the same day diverse other figures passed before his eyes. This repeated itself on numerous occasions.

"The visions were involuntary and he was unable to form an image of any person at will. Most of the time, also, the phantoms were those of persons unknown to him. They appeared during the day as well as during the night, assuming the colors of the natural objects, though they were somewhat paler. After a few days they began also to speak. One month after the onset of this affection, leeches were applied; on the same day the figures became more hazy and less mobile. They disappeared finally after Nicolai had for some time seen only certain portions of some of them."1

Some individuals possess the power of producing hallucinations at will. Goethe had that power. "As I shut my eyes," he said, "and lower my head I figure to myself a flower in the center of my visual organ; this flower does not retain for an instant its original form; it forthwith rearranges itself and from its interior appear other flowers with multicolored or sometimes green petals; they are not natural flowers, but fantastic, though regular, figures like the rosettes of the sculptors. It is impossible for me to fix the creation, but it lasts as long as I desire without increasing or diminishing." l

1 Johannes Mueller, Loc. cit.

In the great majority of cases the judgment, itself disordered, is unable to correct the psychosensory error: the hallucination is taken for a true perception. Though sometimes in the beginning of the disease the subject experiences some doubts, this transitory incertitude is soon replaced by a blind belief in the imaginary perception. "We observe," says Wernicke, "that the reality of a hallucination is maintained against the testimony of all the other senses, and that the patient resorts to the most fantastic explanations, rather than admit any doubt as to the reality of his perception."2 An individual, alone in the open field, hears a voice calling him a thief. He will invent the most absurd hypotheses rather than believe himself a victim of a pathological disorder.

Certain patients, chiefly the feeble-minded and the demented, accept their hallucinations without inquiring as to their origin or mechanism; others on the contrary strive to give explanations which vary with the nature of the malady, the degree of the patient's education and intelligence, and the current ideas of the times. In the middle ages psychosensory disorders were often attributed to diabolic intervention, and this not only by patients but also by their friends. Patients of our own times mostly resort for explanations to the great modern inventions (electric currents, telephone, X-rays, wireless, etc.). Some fancy to themselves apparatus or imaginary forces. One patient attributed his disturbances of general sensibility to a "magnetoelectro-psychologic" current. Another received the visions from a "theologico-celestial projector."

1 Johannes Mueller, Loc. cit.

2 Wernicke. Grundriss der Psychiatrie, p. 126.


Hallucinations are sometimes agreeable, at other times painful, and occasionally, chiefly in dements, indifferent.

In the first case their outward manifestations are an appearance of satisfaction, an expression of happiness, and sometimes ecstatic attitudes.

In the second case, which is the more frequent, the patients become sad, gloomy, or, on the contrary, agitated and violent, a prey to anxiety or anger.

The two kinds of hallucinations, agreeable and painful, are occasionally encountered in the same subject. Sometimes they follow each other without any regular order and are coupled with a variable disposition and incoherent delusions, as in maniacs and in general paralytics; at other times they follow each other somewhat systematically - the painful hallucinations are combated by the agreeable ones. The patients often speak of their persecutors, who insult, threaten, and abuse them, and of their defenders who console them, reassure them, and repair the damage done by the former. A persecuted patient heard a voice call her "a slut"; immediately another voice responded, "He lies; she is a brave woman." Some patients tell of their limbs being smashed and their viscera extracted every night, but that nevertheless they are sound and safe when they arise, thanks to the good offices of their defenders, who properly replace everything. These two sets of hallucinations constitute what the patients sometimes call the attack and the defense.

The indifferent hallucinations are of but little interest. They are met with at the terminal periods of processes of deterioration, and also at the beginning of convalescence in acute psychoses. In the latter case they rapidly become conscious hallucinations and finally disappear.