Also written as héautoscopy. Both terms stem from the Greek words heautou ('of oneself') and skopeô (I am looking at). They translate loosely as 'seeing oneself' or 'seeing [something] of oneself'. In the older literature heau-toscopy is also designated as heautoscopy proper, autohallucination, hallucination of the self, and " dissimilar autoscopy. The German-Greek neologism Heautoskopie was introduced in or shortly before 1935 by the Austrian psychiatrist Erich Menninger-Lerchenthal (d. 1966) to denote an " autoscopic phenomenon in which a hallucinated "doppelgänger or "double is identified as one-self,despitethelackofanexactphysicalresem-blance to the affected individual. In Menninger-Lerchental's own words, "All of a sudden an individual sees himself facing himself. This manifestation looks more or less like himself, but is experienced at any rate, also when it displays certain dissimilarities with the real person, as identical with it, i.e., with one self. This scares the percipient out of his wits, and for a long time it makes a profound impression on him; he cannot ignore this manifestation. To him it is an experience. This act does not constitute a mere visual misperception. It is nothing less than a part of him that is experienced during a few moments." To this Menninger-Lerchenthal adds, "More important than the absolute semblance are any differences between the genuine and the hallucinated body. The latter can be significantly older or younger in appearance. It can also strike the heautoscopist as alien, even though he knows that it is he himself." To emphasize the relative unimportance of the lack of semblance with one's actual physical appearance, the French physician and psychologist Paul Auguste Sollier (1861-1933) had priorly coined the term dissimilar autoscopy to denote this phenomenon. Before Sollier, the German psychiatrist Friedrich Wilhelm Hagen (1814-1888) had referred to the same phenomenon by the term "deuteroscopy. Heau-toscopy may be accompanied by somaesthetic or vestibular sensations and feelings of dere-alization and depersonalization. Phenomenolog-ically, heautoscopic doubles tend to present as diaphanous or 'ghost-like' three-dimensional bodies. In cases where more than one double is perceived, the term " polyopic heautoscopy applies. The earliest known account of polyopic heautoscopy was published in 1826 by the German physiologist and zoologist Johannes Peter Müller (1801-1858). Where some doubles in polyopic heautoscopy are perceived as men and others as women, the term "heterosexual heautoscopy is used. The term " negative heautoscopy is a synonym for "negative autoscopy (i.e. the transient failure to perceive one's own mirror image in a mirror). The term 'heautoscopy without optical image' is a synonym for " sensed presence. Heau-toscopy may occur in healthy individuals, but it has also been described in the context of a variety of neurological and psychiatric disorders. Eti-ologically, it is associated with conditions such as epilepsy, migraine, brain tumour, ischaemia, and infection, but also with psychiatric disorders such as " psychotic disorder, mood disorder, anxiety disorder, and " dissociative disorder. Pathophysiologically, heautoscopy is associated primarily with aberrant neuronal activity in an area at the temporo-parieto-occipital junction. It is sometimes classified as a variant of the group of " reduplicative hallucinations.
References
Brugger, P., Blanke, O., Regard, M., Bradford, D.T., Landis, Th. (2006). Polyopic heautoscopy: Case report and review of the literature. Cortex, 42, 666-674.
Hagen, F.W. (1837). Die Sinnestäuschungen in Bezug auf Psychologie, Heilkunde und Rechtspflege. Leipzig: Otto Wigand.
Menninger-Lerchenthal, E. (1935). Das Truggebilde der eigenen Gestalt. Heautoskopie, Doppelgänger. Abhandlungen aus der Neurologie, Psychiatrie, Psychologie und ihren Grenzgebieten, 74, 1-196.
Müller, J. (1826). Ueber die phantastischen Gesichtserscheinungen. Koblenz: Hölscher.
Sollier, P. (1903). Les phénomènes d'autoscopie. Paris: Félix Alcan.
Dictionary of Hallucinations. J.D. Blom. 2010.