Visual experi­ence during a sensi­tive period is crucial for the normal devel­op­ment of the brain. Individ­u­als who are treated for congen­i­tal cataracts more than a few weeks from birth suffer from low visual acuity as well as specific deficits (such as impaired face process­ing). This project inves­ti­gates the possi­ble mecha­nisms that mediate this sensi­tive period, by non-invasively assess­ing brain struc­ture and function in congen­i­tally and devel­op­men­tally visually deprived individuals.

Individ­u­als who were born totally blind and have their sight restored in later child­hood continue to suffer from visual impair­ments. This is presum­ably due to a lack of relevant visual experi­ence within time windows of height­ened plastic­ity during brain devel­op­ment, called sensi­tive periods. If visual input is not received during this time, animal research has suggested that the struc­tural and functional organi­za­tion of the brain is not properly tuned, result­ing in impaired behav­ior. Studies in sight recov­ery individ­u­als offer a unique oppor­tu­nity to under­stand the neural mecha­nisms of sensi­tive periods in humans. Results will allow us to under­stand how early experi­ence affects future brain function­ing and behav­ior — a key open question in neuro­science with a high impact on quality of life and socioe­co­nomic development.

This doctoral project is part of a collab­o­ra­tion between Hector Fellow Prof. Dr. Brigitte Röder, and the LV Prasad Eye Insti­tute in Hyder­abad, India, provid­ing access to humans with special sight histo­ries. We work with individ­u­als born with dense congen­i­tal bilat­eral cataracts, who later undergo cataract removal surgery. We use non-invasive neuro­science methods to access brain parame­ters in this group, and compare them with individ­u­als who suffered a transient phase of visual depri­va­tion later in life. Brain parame­ters will be related to behav­ioral outcomes, allow­ing us to better tailor rehabil­i­ta­tion efforts for the visually impaired. Addition­ally, the project will help us under­stand how learn­ing at differ­ent ages can be promoted.