Researchers led by neuroscientists at Georgetown University Medical Center say this helps explain why the blind have such advanced perception of these senses, abilities that far exceed those of people who can see, a Georgetown release says.
The study suggests the different functional attributes that make up vision, such as analysis of space, patterns and motion, still exist in the visual cortex of blind individuals.
But instead of using those areas to understand what the eyes see, the blind use them to process what they hear and touch, because the same components are necessary to process information from those senses.
"We can see that in the blind, large parts of the visual cortex light up when participants are engaged in auditory and tactile tasks. This is in addition to the areas in their brain that are dedicated to processing sound and touch," said Josef P. Rauschecker, a professor in the Department of Physiology and Biophysics at GUMC.
"This shows us that the visual system in the blind retains the functional organization that was anatomically laid out by genetics, but that the brain is plastic enough to use these modules to analyze input they receive from different senses.
"The neural cells and fibers are still there and still functioning, processing spatial attributes of stimuli, driven not by sight but by hearing and touch."
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