Delusion of parasitosis or chronic tactile hallucinosis: hypothesis about their brain physiopathology

Compr Psychiatry. Jan-Feb 1992;33(1):25-33. doi: 10.1016/0010-440x(92)90075-2.


The abnormal belief of having the skin infested by parasites is a syndrome with different etiologies. Approximately 12% of cases are induced by another patient with the same syndrome. In noninduced cases, two physiopathological brain mechanisms have been proposed: a delusion, or a primary abnormal tactile sensation with a secondary delusional elaboration. These two hypotheses have been characterized by Berrios as cognitive and sensorialist approaches, respectively. Although modern literature defines this syndrome as a delusion, early literature, particularly German, described both approaches, and even emphasized the sensorialist approach, classifying it as a chronic tactile hallucinosis. A thorough review of the literature suggests both mechanisms may be possible.

Publication types

  • Review

MeSH terms

  • Brain / physiopathology*
  • Delusions / physiopathology*
  • Delusions / psychology
  • Ectoparasitic Infestations / physiopathology*
  • Ectoparasitic Infestations / psychology
  • Hallucinations / physiopathology*
  • Hallucinations / psychology
  • Humans
  • Neurocognitive Disorders / physiopathology*
  • Neurocognitive Disorders / psychology
  • Sensation / physiology
  • Touch / physiology*