Enhanced hearing in adult ‘blind’ mice provides future hope for human sensory enhancements
It may sound like it came out of a comic book — gaining enhanced hearing after being deprived of sight. But the phenomenon isn’t just limited to superheroes named Daredevil.
Called the Ray Charles Effect, young, blind children have been known to develop a stronger hearing ability due to their malleable minds’ ability to rewire the sensory circuits of their brain. Now, researchers at the University of Maryland and Johns Hopkins University think that the same could apply to adults.
An NIH-funded study, published Wednesday in the science journal Neuron, shows that the brains of adult mice could be rewired after the rodents were given temporary vision loss. The mice, each having normal vision and hearing, were placed in complete darkness for six to eight days. Once returned to a normal light-dark cycle, their vision was unchanged, but the mice were now able to hear much better than before. Upon further study, the rodents’ neurons in their auditory cortex — the part of the brain devoted to hearing — had changed, firing faster and more powerfully.
The enhanced hearing did wear off after a few weeks. But the results had the research team convinced that if an adult cortex — which is fundamentally the same in most mammals — could be changed in the adult mouse, then auditory senses, among others, could be made flexible in most mammals.
“We can perhaps use this to benefit our efforts to recover a lost sense,” said associate professor of neuroscience at Johns Hopkins University Hey-Kyoung. “By temporarily preventing vision, we may be able to engage the adult brain to change the circuit to better process sound.”
Lee believes the research could eventually lead to future treatments for hearing loss or tinnitus in humans, though the next step for the researchers is to find a way to make the sensory changes permanent.