Nature and nurture in neurocognitive development: insights from studies of plasticity in blindness

Colloquium | September 28 | 3:30-5 p.m. | 101 Life Sciences Addition

 Marina Bedny, Johns Hopkins University

 Department of Psychology

The human cortex consists of distinct networks that support cognitive functions such as language processing, face perception, and motor control. How do intrinsic physiology and experience determine this specialization? Studies of sensory loss provide unique insights into this question. In individuals who are blind from birth so called “visual” cortices acquire responses to sound and touch. Traditionally, these cross-modal responses were assumed to reflect processes analogous to vision (e.g. discrimination of tactile patterns and localization of sound). Contrary to this idea, I will present evidence that visual cortices of those who are blind from birth take on higher-cognitive functions, including language and numerical processing. This reorganization occurs during childhood and appears to follow a critical period. Resting state data suggest that plasticity is enabled in part by front-parietal connectivity with occipital cortices. Evidence from blindness supports the view that human cortices are highly functionally flexible during development and early experience plays a key role in determining function.