For many decades, neuroscientists hypothesized that the brain could learn to make meaning of visual information around the age of 6 or 7.

A recent study conducted by Professor Pawan Sinha at MIT disclosed that several studies of children in India who underwent surgery to remove congenital cataracts after age 7 showed that older children may acquire visual tasks such as recognizing faces, differentiating objects from a background, and perceiving motion.

The researchers utilized diffusion tensor imaging to examine structural alterations in the brain, which can show changes in the organization of white matter – bundles of nerve fibers that connect different brain parts. Diffusion tensor imaging measures mean diffusivity and fractional anisotropy by tracking the movement of hydrogen nuclei in water molecules. Changes in the organization of the white matter — bundles of nerve fibers that link various areas of the brain — can be seen by this sort of imaging.

The researchers detected modifications in white matter pathways in the visual systems later stages, which are thought to be involved in higher-order tasks such as facial perception. These improvements happened gradually over several months after the procedure.

The researchers then examined the individuals performance on several visual tasks. They discovered that the degree of structural change in the white matter pathways linked with the higher-order visual function was correlated with their ability to discriminate faces from other objects. 

According to the study, children who had cataracts removed at a younger age exhibited larger and faster advances in face-perception ability than older children.

 Prof Sinha further stated that the findings show that older children can benefit from this type of surgery and that it should be made available to them. If the brain has such remarkable abilities to reconfigure and even change its structure, we should take advantage of that plasticity and treat children of all ages.

(Source: https://theprint.in/health/researchers-identify-anatomical-changes-in-brains-after-patients-sight-is-restored/1550168/)