Convergence micropsia

Convergence micropsia is a type of micropsia characterized by the reduction in apparent size of objects viewed when the eyes are more converged than they need to be for the distance of the object from the eyes.[1][2][3]

It occurs mainly during stereoscopy and when viewing autostereograms (such as Magic Eye pictures). In these cases, the object is depicted by the two half images of a stereogram or by the contents of the autostereogram. Moving the stereogram or the autostereogram closer to the eyes increases convergence of the eyes and reduces the apparent size of the depicted object. If a correctly arranged stereogram or autostereogram is viewed with crossed eyes, then the depicted objects will appear smaller than if it is viewed with eyes diverged or parallel.

Convergence micropsia could also occur if one looked at the world through base-out prisms.

  1. ^ Enright JT (1989). "The eye, the brain and the size of the moon : Toward a unified oculomotor hypothesis for the moon illusion". In Hershenson, Maurice (ed.). The Moon illusion. Hillsdale, N.J: L. Erlbaum Associates. pp. 59–121. ISBN 978-0-8058-0121-7.
  2. ^ Enright JT (1989). "Manipulating stereopsis and vergence in an outdoor setting: moon, sky and horizon". Vision Res. 29 (12): 1815–24. doi:10.1016/0042-6989(89)90162-4. PMID 2631401. S2CID 26009881.
  3. ^ Hollins M (September 1976). "Does accommodative micropsia exist?". Am J Psychol. 89 (3). The American Journal of Psychology, Vol. 89, No. 3: 443–54. doi:10.2307/1421617. JSTOR 1421617. PMID 998809.