Rewriting Life

Hearing Tests Could Be Vital Concussion Indicator

Researchers believe a blow to the head temporarily disrupts the way the brain processes spoken sound.

In a study at Northwestern University, a boy listens to a series of sounds while electrodes measure his brain activity to help diagnose a concussion.

A test that measures the brain’s response to speech could provide a new way to diagnose concussions and track patients’ progress toward recovery, a small study suggests.

Developed by researchers at Northwestern University, the test is meant to detect neural activity when patients are exposed to auditory stimuli. Since one of the common side effects of concussion is a compromised ability to make sense of sound, researchers believe a blow to the head temporarily disrupts the way the brain processes and hears speech.

Led by Nina Kraus, a professor and director of Northwestern’s Auditory Neuroscience Laboratory, scientists built a test using electrodes to measure the electrical signals generated in the brain. The team placed three electrodes on children’s scalps while the subjects listened to several minutes of various spoken sounds designed to assess their ability to understand speech and distinguish between certain sounds.

Researchers observed differences in neural response among children who suffered concussions in the past five to 56 days compared to children without concussions. Children with concussions had reduced reactions to the pitch of the recorded sounds than the control group. The test was able to correctly identify 18 out of 20 study participants with a concussion and 19 out of 20 healthy controls. As the children recovered from their head injuries, their ability to process pitch improved, the researchers reported.

One limitation of the study was that it did not measure participants’ baseline sound processing before a concussion, says Marc Nuwer, a clinical neurophysiologist and professor of neurology at UCLA School of Medicine. That would have helped determine whether the patterns in a subject’s auditory processing were different than normal. Nuwer says injuries other than concussions, medications, and fatigue can also affect the brain’s ability to process sound.

While the initial results are interesting, such a test may not be practical in a doctor’s office or in the field. The equipment needed to conduct the test—an electroencephalogram machine—is expensive, and the analysis of results is complicated.

Kraus says her team will be recruiting more study participants to try the test in a bigger population.

Traumatic brain injuries account for more than two million emergency room visits in the United States each year and contribute to the deaths of more than 50,000 Americans, according to the U.S. Centers for Disease Control and Prevention. A significant percentage of these injuries are considered to be mild ones, which include concussion. Currently, doctors rely on symptoms to diagnose concussions. Computerized tomography scans can rule out more serious brain injuries, but they can’t detect concussion.

Increased worries about long-lasting brain injury in both youth and professional sports players have resulted in more public awareness of concussions and an interest in developing better diagnostic methods. Concussions in children are particularly difficult to diagnose.

Get stories like this before anyone else with First Look.

Subscribe today
Already a Premium subscriber? Log in.
In a study at Northwestern University, a boy listens to a series of sounds while electrodes measure his brain activity to help diagnose a concussion.

Uh oh–you've read all of your free articles for this month.

Insider Premium
$179.95/yr US PRICE

More from Rewriting Life

Reprogramming our bodies to make us healthier.

Want more award-winning journalism? Subscribe and become an Insider.
  • Insider Premium {! insider.prices.premium !}*

    {! insider.display.menuOptionsLabel !}

    Our award winning magazine, unlimited access to our story archive, special discounts to MIT Technology Review Events, and exclusive content.

    See details+

    What's Included

    Bimonthly magazine delivery and unlimited 24/7 access to MIT Technology Review’s website

    The Download: our daily newsletter of what's important in technology and innovation

    Access to the magazine PDF archive—thousands of articles going back to 1899 at your fingertips

    Special discounts to select partner offerings

    Discount to MIT Technology Review events

    Ad-free web experience

    First Look: exclusive early access to important stories, before they’re available to anyone else

    Insider Conversations: listen in on in-depth calls between our editors and today’s thought leaders

  • Insider Plus {! insider.prices.plus !}* Best Value

    {! insider.display.menuOptionsLabel !}

    Everything included in Insider Basic, plus ad-free web experience, select discounts to partner offerings and MIT Technology Review events

    See details+

    What's Included

    Bimonthly magazine delivery and unlimited 24/7 access to MIT Technology Review’s website

    The Download: our daily newsletter of what's important in technology and innovation

    Access to the magazine PDF archive—thousands of articles going back to 1899 at your fingertips

    Special discounts to select partner offerings

    Discount to MIT Technology Review events

    Ad-free web experience

  • Insider Basic {! insider.prices.basic !}*

    {! insider.display.menuOptionsLabel !}

    Six issues of our award winning magazine and daily delivery of The Download, our newsletter of what’s important in technology and innovation.

    See details+

    What's Included

    Bimonthly magazine delivery and unlimited 24/7 access to MIT Technology Review’s website

    The Download: our daily newsletter of what's important in technology and innovation

/
You've read all of your free articles this month. This is your last free article this month. You've read of free articles this month. or  for unlimited online access.