X-Nico

unusual facts about stereopsis recovery



Critical period hypothesis

Recently, doubts have arisen concerning the validity of this critical period hypothesis with regard to visual development, in particular since the time it became known that neuroscientist Susan R. Barry and others have achieved stereopsis as adults, long after the supposed critical period for acquiring this skill.

Susan R. Barry

Barry had initially found it difficult to believe in her acquisition of stereo vision for the reason that the notion of critical period was firmly set since the groundbreaking work of Torsten Wiesel and David H. Hubel with deprivation experiments in which animals did not develop the neuronal basis for stereo vision if they were prevented from performing stereo fusion for a given time period after birth.

Vision therapy

It is to be noted that the vision therapy approach that is widespread in the U.S. and which has led to recover stereopsis in a number of persons, most notably Susan R. Barry, is diametrically opposed to the use of prisms in the manner that is advocated in the MKH method.


see also