Stereoblindness (also stereo blindness) is the inability to see in 3D using stereopsis, or stereo vision, resulting in an inability to perceive stereoscopic depth by combining and comparing images from the two eyes.
Individuals with only one functioning eye always have this condition; the condition also results when two eyes do not function together properly.
Most stereoblind persons with two healthy eyes do employ binocular vision to some extent, albeit less than persons with normally developed eyesight. This was shown in a study in which stereoblind subjects were posed with the task of judging the direction of rotation of a simulated transparent cylinder: the subjects performed better when using two eyes than when using their preferred eye. They appeared to judge the direction of rotation from the images in each eye separately and then to combine these judgments, rather than relying on differences between the images in the two eyes. Also, purely binocular motion stimuli appear to influence stereoblind persons' sensation of self-motion. Furthermore, in some cases each eye can contribute to peripheral vision for one side of the field of view (see also monofixation syndrome).
However, there is an exception to this: those with a true congenital alternating squint. Those with true congenital alternating squints have two healthy eyes, and the ability to switch (by choice) between seeing with either eye. However, stereoscopic and three dimensional vision can never be achieved in this condition (attempts to train those with true congenital alternating squints into binocular vision results in double vision, which can be irreversible).
It has been suggested that Dutch Old Master Rembrandt may have been stereoblind, which would have aided him in flattening what he saw for the production of 2D works. Scientists have suggested that more artists seem to have stereoblindness when compared with a sample of people with stereo-acuteness (normal stereo vision).
British neurologist Oliver Sacks lost his stereoscopic vision in 2009 due to a malignant tumor in his right eye and had no remaining vision in that eye. His loss of stereo vision was recounted in his book The Mind's Eye, published in October 2010.
- Christa M. van Mierlo; Eli Brenner; Jeroen B.J. Smeets (2011). "Better performance with two eyes than with one in stereo-blind subjects' judgments of motion in depth". Vision Research. 51 (11): 1249–1253. doi:10.1016/j.visres.2011.03.015. PMID 21458479.
- Jeremy M. Wolfe; Richard Held (March 1980). "Cyclopean stimulation can influence sensations of self-motion in normal and stereoblind subjects". Perception & Psychophysics. 28 (2): 139–142. doi:10.3758/bf03204339.
- Marmor M. F., Shaikh S., Livingstone M. S., Conway B. R., Livingstone MS, Conway BR (September 2004). "Was Rembrandt stereoblind?". N. Engl. J. Med. 351 (12): 1264–5. doi:10.1056/NEJM200409163511224. PMC 2634283. PMID 15371590. Lay summary – New York Times (September 16, 2004).
- Rembrandt (van Rijn)
- New York Times: A defect that may lead to a masterpiece (June 13, 2011)
- "The Man Who Forgot How to Read and Other Stories", BBC accessed 30 June 2011
- Murphy, John. "Eye to Eye with Dr. Oliver Sacks", Review of Optometry, 9 December 2010
- Peck, Morgen (2012-07-19). "How a movie changed one man's vision forever". BBC News. Retrieved July 20, 2012.
- Susan Barry (2009). Fixing My Gaze: A Scientist's Journey Into Seeing in Three Dimensions. New York: Basic Books. ISBN 0-465-00913-1.