Pseudohallucinations

PSEUDOHALLUCINATIONS, psychopathological phenomena related to hallucinations (see), but differing from them by the absence of a connection with real space. The best description of pseudohallucinations was given by Kandinsky, the author of a special work on them. Visual pseudohallucinations are vivid images that can be sharply projected outward and thus appear to stand before the eyes, yet simultaneously bear no relation to the black field of vision of closed eyes: to see them, one must divert attention from this field of vision; they do not possess the character of objectivity. According to Kandinsky's self-observations, the most favorable condition for the emergence of pseudohallucinations was the complete cessation, whenever possible, of voluntary mental activity, with attention directed without any strain solely to the internal activity of that sense whose pseudohallucinations were being observed. Based on a phenomenological analysis of pseudohallucinations, Jaspers considers them not to be perceptual deceits, but merely vivid representations, and therefore distinguishes them not only from true hallucinations but also from fantastic visual images during fatigue or before falling asleep, which are observed precisely in the external field (other authors do not make this distinction). From normal representations, pseudohallucinations differ by the extraordinary vividness and detail normally inherent only in perceptual images. They can persist as prolonged constant phenomena and then disappear all at once; finally, they cannot be voluntarily produced and modified by their subject, who is always passive in relation to them. Certain forms of pseudohallucinations are sometimes observed in healthy people as well. They cannot be entirely delimited from so-called «eidelitic phenomena», although they are not identical to the latter. Pseudohallucinations of schizophrenics bear a clearly expressed pathological character; these patients frequently say that they hear their «voices» in the head or see visions in some special space that does not coincide with the space of the external world. Akin to these pseudohallucinations are peculiar experiences when patients feel that «foreign» thoughts are being inserted into them. These thoughts are most frequently localized by them in the tongue, in which corresponding muscular sensations arise, creating the illusion of the patient's compulsory performance of acts contrary to their will. The addition of these states to pseudohallucinations corresponds to the content that the French psychiatrist Baillarger invested in the concept of «psychic hallucinations», and compels the inclusion of this entire complex in Clerambault's syndrome of «psychic automatism», which is characterized by the fact that the phenomena comprising it are experienced by patients as arising automatically and unconnected with their personality, even though they occur within their psyche. Undoubtedly, true hallucinations, contrary to Jaspers' opinion, are connected to pseudohallucinations by a whole series of gradual transitions. Pathogenetically, pseudohallucinations owe their origin apparently not to the irritation of certain cerebral centers, but, conversely, to a decrease in mental activity, which liberates passive and involuntary imaginative activity that is usually suppressed and remains unconscious. The differentiation of pseudohallucinations from true hallucinations does not possess great clinical and differential-diagnostic significance.