When vision is lost, a person’s senses of touch and hearing become enhanced. But exactly how this happens has been unclear. And why do we have two eyes that face forward, rather than eyes on the sides of heads, the way most animals do?
Complete loss of vision leads to profound changes in the visual cortex of the brain. Researcher Alvaro Pascual-Leone says, “In our studies [in which a group of sighted study subjects were blindfolded for five days], we have shown that even in an adult, the normally developed visual system quickly becomes engaged to process touch in response to complete loss of sight.”