- Also known as tessellated hallucination. Both terms are indebted to the Greek words tessera (a small tile used in mosaics), and opsis (seeing). The term tessellopsia was coined in or shortly before 1999 by the British neuroscientists Dominic H. ffytche and Robert J. Howard. It is used to denote a "geometric hallucination consisting of repeated geometrical patterns featuring tiles, brickwork, triangles, hexagonal figures, grid-like patterns, latticed patterns, or network patterns. Phenomenologically, tessallopsia would seem to overlap with some of the * form-constants of * geometric hallucinations as described by the German-American biological psychologist and philosopher Heinrich Klüver (1897-1979). It is distinguished somewhat arbitrarily from * dendropsia. Tessellopsia has been described as an * aura occurring in the context of paroxysmal neurological disorders such as migraine and epilepsy, in the context of *Charles Bonnet syndrome, and after the use of * hallucinogens such as LSD and mescaline. The notion oftessellopsia should not be confused with "mosaic vision.Referencesffytche, D.H., Howard, R.J. (1999). The perceptual consequences of visual loss: 'Positive' pathologies of vision. Brain, 122, 1247-1260.Mocellin, R., Walterfang, M., Velakoulis, D. (2006). Neuropsychiatry of complex visual hallucinations. Australian & New Zealand Journal of Psychiatry, 40, 742-751. Santhouse, A.M., Howard, R.J., ffytche, D.H. (2000). Visual hallucinatory syndromes and the anatomy of the visual brain. Brain, 123, 2055-2064.
Dictionary of Hallucinations. J.D. Blom. 2010.