The brain after blindness: How newly-sighted people build a visual world

"If we told them to look at the face, they could usually manage it. But they were mostly looking at the hands. The Prakash children eventually learn to look at faces when spoken to - usually a few months after their surgeries. Their experiences reveal that seeing doesn't come naturally the moment a person is cured of blindness. Newly-sighted people must learn to see."

"Congenital cataracts are a preventable cause of blindness and are often treatable within two months of birth. However, due to a lack of access to cataract screening and surgery, many children in developing countries are often treated too late, if at all. With advances in sight-restoration technologies, such as gene and stem cell therapies, and greater access to cataract surgery, many more people may gain sight even after decades of blindness."

"Understanding how and why vision works differently for those who gain sight later in life, as compared to those who can see from birth, could help the newly-sighted see better. A newborn's vision is blurry. It takes time before things come into focus. Binocular vision develops by the third month, and it takes a couple more months before babies can perceive distances."

MIT researcher Sharon Gilad-Gutnick studies children who regain sight after cataract surgery through Project Prakash in India. These newly-sighted children struggle with face recognition and initially avoid looking at faces, preferring to look at hands instead. Over months following surgery, they gradually learn to direct their gaze toward faces during social interaction. This research demonstrates that seeing is not an automatic ability that emerges once blindness is cured. Instead, the visual system requires time and experience to develop proper neural pathways and behavioral patterns. As sight-restoration technologies advance through gene therapy and stem cell treatments, understanding how the brain learns to process visual information in those gaining sight later in life becomes increasingly important for improving outcomes.

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