phantom boarder syndrome

(PBS)

   Also known as phantom boarder symptom. The expression phantom boarder symptom was introduced in or shortly before 1984 by the American psychiatrist and sex therapist Edward L. Rowan to denote a delusional syndrome involving the belief that someone uninvited is living in the affected individual's house (typically in the attic or on an upper floor). This delusional belief may occur in isolation or it may be secondary to hallucinatory experiences. In individuals suffering from dementia, it may be related to cognitive impairment and memory disturbances, and sometimes to the inability to recognize oneself in the mirror. In the latter case, the concomitant staring behaviour is called a *mirror sign. On the basis of primary factor analyses, PBS has been classified as a *misidentification syndrome. However, it is open to debate whether PBS is thematically and conceptually compatible with the other categories of the misidentification syndrome, whether it is worthy of the predicate syndrome (which would suggest that the cluster of symptoms may have a common pathophysiolog-ical and/or etiological origin), and even whether it is worthy of the predicate symptom. It would perhaps be more accurate to speak of a cluster of symptoms with a common or stereotyped theme. In most clinical descriptions, this cluster of symptoms includes paranoia, paranoid delusions, "illusions, * auditory hallucinations, * visual hallucinations, and sometimes hallucinations in any of the other sensory modalities. Symptoms like these are known to occur quite frequently in individuals with a clinical diagnosis of * schizophrenia spectrum disorder, as well as in Alzheimer's disease and other forms of dementia. In his textbook of 1913 the German psychiatrist Emil Kraepelin (1856-1926) describes many of the hallucinatory and paranoid delusional symptoms that are now attributed to PBS as symptoms in the context of paranoiden Verblödungen (i.e. 'paranoid madnesses') or paraphrenias. Kraepelin's text gives no indication of whether he regards these symptoms as standing out in any particular fashion from other paranoid symptoms. Nevertheless, his work on the paraphrenias is sometimes quoted as a conceptual precursor of PBS. The French notion of délire du compagnon tardif, which features in the 1972 thesis of the Portuguese psychiatrist José Carlos Dias Cordeiro, would seem to be a closer match with the notion of the phantom boarder syndrome.

   References

   Dias Cordeiro, J. (1972). Les États délirants tardifs. Approche phénoménologique et psycho-dynamique. L'Évolution Psychiatrique, 37, 331-347.

   Kasahara, H., Tsumura, M., Kada, H., Hashidume, T., Ito, T., Ochiai, Y., Hiruma, Y., Furukawa, H., Nakanishi, T. (2005). Perspectives on phantom boarder symptom. Psychogeriatrics, 5, 103-107.

   Kraepelin, E. (1913). Psychiatrie. Ein Lehrbuch für Studierende und Ärzte. III. Band. Klinische Psychiatrie. II. Teil. Achte, vollständig umgearbeitete Auflage. Leipzig: Verlag von Johann Ambrosius Barth.

   Rowan, E.L. (1984). Phantom boarders as a symptom of late paraphrenia. American Journal of Psychiatry, 141, 580-581.

   Spangenberg Postal, K. (2005). The mirror sign delusional misidentification symptom. In: The lost self. Pathologies ofthe brain and identity. Edited by Feinberg, T.E., Keenan, J.P. Oxford: Oxford University Press.