Researchers found minimizing a person's sense of sight for as little as a week could improve their hearing.
Blind musicians such as Stevie Wonder and Ray Charles are examples of people who have had an elevated sense of hearing by losing their site, a Johns Hopkins University news release reported. This recent study looked at why this phenomenon occurs.
The research team looked at how sight and hearing work together in rodents' brains.
"In my opinion, the coolest aspect of our work is that the loss of one sense - vision - can augment the processing of the remaining sense, in this case, hearing, by altering the brain circuit, which is not easily done in adults," Hey-Kyoung Lee, an associate professor of neuroscience and researcher at the Mind/Brain Institute at the Johns Hopkins University said in the news release. "By temporarily preventing vision, we may be able to engage the adult brain to now change the circuit to better process sound, which can be helpful for recovering sound perception in patients with cochlear implants for example."
The team placed mice in darkened environments for about a week and analyzed how they responded to different sounds. They then compared these responses with mice that were in a well-lit environment.
The researchers noticed the mice in the darkened environment showed a change in the brain circuitry in the primary auditory cortex, which processes sound.
"Our result would say that not having vision allows you to hear softer sounds and better discriminate pitch," Lee, said. "If you ever had to hear a familiar piece of music with a loud background noise, you would have noticed that sometimes it seems the beat or the melody is different, because some of the notes are lost with the background. Our work would suggest that if you don't have vision you can now rescue these 'lost' notes to now appreciate the music as is."
The findings suggest sensory areas of the brain called thalamocortical inputs can be reactivated if another sense is restricted.
"We don't know how many days a human would have to be in the dark to get this effect, and whether they would be willing to do that," biologist Patrick Kanold of the University of Maryland, said in the news release. "But there might be a way to use multi-sensory training to correct some sensory processing problems in humans."
After a few weeks of having regular sight the mice reverted back to their normal hearing levels.
