dysmorphopsia

   The term dysmorphopsia comes from the Greek words dus (bad), morphè (form), and opsis (seeing). It translates roughly as the inability to perceive the proper form of objects. In a restricted sense, the term dysmorphopsia is used to denote a variant of "metamorphopsia in which lines appear wavy. In this version, dysmorphopsia is associated primarily with bilateral occipital cortical damage, due to carbon monoxide poisoning, for example, or to the use of psychotomimetic substances such as cocaine, LSD, or mescaline. As exemplified by the work of the German psychiatrist Carl Schneider (1891-1945), the term dysmorphopsia used to have a broader connotation during the first decades of the 20th century, denoting something like the present umbrella term metamorphopsia. Conversely, the term metamorphopsia is used by the Danish neuroscientists Villars Lunn, Axel Klee (19331982?), and Rolf Willanger to denote a visual distortion in which objects appear to have distorted contours (i.e. what is now called dysmorphopsia).

   References

   ffytche, D.H., Howard, R.J. (1999). The perceptual consequences of visual loss: 'positive' pathologies of vision. Brain, 122, 1247-1260. Klee, A., Willanger, R. (1966). Disturbances of visual perception in migraine. Acta Neurolog-ica Scandinavica, 42, 400-414. Lunn, V. (1948). Om legemsbevidstheden. Copenhagen: Ejnar Munksgaard. Schneider, C. (1930). Die Psychologie der Schizophrenen und ihre Bedeutung für die Klinik der Schizophrenie. Leipzig: Georg Thieme Verlag.