Our ability to perceive the rich, three-dimensional nature of the world depends on stereopsis. It is a process by which the brain combines slightly different images from each eye (binocular disparity) into a single depth-rich view. This function plays a vital role in accurate depth estimation, visuomotor control, and many everyday tasks.

However, not everyone shares the same capacity for stereovision. Around 5 percent of the population is considered stereo-deficient, and in older adults, this figure might rise above 34 percent. While people without stereopsis can still rely on monocular cues (such as perspective and occlusion), binocular disparity is key for fine depth judgments and complex motor tasks. A lack of stereovision can affect activities such as sports, reduce safety in older age, and limit career options for roles such as drivers, pilots, and surgeons.

It has long been believed that stereovision develops early in life (between a few months to 5 years of age) and that outside of this critical period, recovery is not possible. However, there are interesting accounts of improvement in adulthood. In the 19th........

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