Listen closely: Can you hear that noisy static in your brain?
Neurobiologist Nina Kraus can. At her lab at Northwestern University called “Brainvolts,” she and her colleagues can attach a series of electrodes to your scalp and record the electricity your brain produces in response to a sound.
“I can then take that electricity and play it out through a speaker and we can listen to your brain to see how well it does that job,” Kraus said. “By doing that we can gain insight to the health of your brain and nervous system.”
If your brain was exposed to a rich sound environment, Kraus says, filled with linguistic and musical stimulation, you’re more likely to have less neural static.
If, however, you grew up with limited enrichment, your brain may be excessively noisy – and may literally interfere with your brain’s ability to decipher auditory input.
“The brain is hungry for information and it actually creates electrical activity when it doesn’t get enough,” Kraus explained. “But it creates random and staticky activity, which in the end is more of a problem because it gets in the way of making sense of sound.”
Playing sports tampers brain static
Now it appears that playing sports may play a role in the brain’s ability to hear properly.
In a new study published Monday in the journal Sports Health, Kraus and her team discovered elite athletes have less static in their brains than non-athletes.
“Compared to non-athletes, elite athletes can better process external sounds, such as a teammate yelling a play or a coach calling to them from the sidelines, by tamping down background electrical noise in their brain,” she said.
“I’m intrigued by the findings,” said neurologist Dr. Richard Isaacson, who directs the Neurology Residency Training Program and the Alzheimer’s Prevention Clinic at Weill Cornell Medical College.
“I don’t think it’s just physical and cardiovascular fitness, it’s mental fitness as well,” said Isaacson who was not involved in the study. “It’s likely multimodal. I would like to see if can repeat this across multiple different universities and then segregate out the non-contact versus contact sports, such as soccer versus badminton.”
A tough job for the brain
The new study is part of a five-year analysis of the neural processing of sound in sports concussions, funded by the National Institutes of Health. Launched last year, the research will follow the brain health of 495 Northwestern student athletes and 493 age- and sex-matched control students.
By analyzing the electrical responses to sound that happen in the brain after an athlete sustains a concussion, Kraus hopes to be better able to biologically determine when that athlete is ready to return to play without further damage to the brain.
“Making sense of sound is one of the hardest jobs that we ask our brain to do,” Kraus explained. “The brain must decipher a sound’s pitch, timing and harmonics to understand the meaning, often within microseconds.”
At this point in the study, Kraus has found similar responses in the brain of athletes across all of types of sports, with no difference in gender.
“As the years go on and we follow the same athlete, we will be better able to understand how their neural noise changes over time, or how it may possibly differ from one sport to another, especially high-contact sports,” Kraus said.
Prior studies show there are ways to improve the brain’s response to sound, Kraus said, such as learning a second language or playing a musical instrument, which are being used to help children with processing difficulties and the elderly with hearing loss.
Interestingly, the ways in which those behaviors impact the brain are completely different than the neural dampening that occurs in elite athletes.
“Playing a musical instrument will strengthen the processing of the signal – the strength of the signal,” Kraus said. “It doesn’t do anything to the background noise.”
Still, Kraus is hopeful that the current research will results in new techniques that can be used to help those with auditory processing or other disorders, as well as concussions.
“Physical activity seems to track with a quieter nervous system,” Kraus said. “If you have a healthier nervous system and brain, you may be able to better handle injury or other health problems.”.