A quick test may be all it takes to identify children who have learning disabilities or literary challenges long before they actually learn to read.

According to a new study at Northwestern University, a child’s ability to decipher sounds — more specifically, consonants — in a noisy environment may be an indicator of future language and reading difficulties. The preliterate children whose brains more inefficiently process speech against a chaotic background are more likely to develop these difficulties than their peers, researchers found.

Noisy environments, such as homes with television or radios blaring along with the loud voices of children, noisy city landscapes, and loud classrooms all have the ability to disrupt brain mechanisms necessary for literary development in schoolchildren. Speech often occurs in these environments, however disruptive they are. In the chaos, consonants are particularly at risk of being lost to the ear, as they are quicker and more acoustically complicated than vowels.

The study involved outfitting the scalps of 112 kids between the ages of 3 and 14 with EEG wires. Researchers were able to assess the way the brain reacted to consonants played amid noise into the children’s headphones. After capturing various aspects of how the brain responded to the sounds, scientists were able to create a statistical model to predict the children’s performance on early literacy tests.

They found that their model very accurately predicted the performance of 3-year-old children on several pre-literacy tests, and how, a year later at age 4, the child will perform on multiple language skills necessary for reading. The model also accurately predicted the reading abilities of school-aged children, and if they had been diagnosed with a learning disorder.

"Sound is a powerful, invisible force that is central to human communication," said study senior author Nina Kraus, director of Northwestern's Auditory Neuroscience Laboratory in a press release. "Every day listening experiences bootstrap language development by cluing children in on which sounds are meaningful. If a child can't make meaning of these sounds through the background noise, he or she won't develop the linguistic resources needed when reading instruction begins."

This new link between the way a child’s brain processes spoken information amid background noise and reading skill in preliterate children provides a glimpse into a child’s future, allowing early action to combat literary troubles.

"There are excellent interventions we can give to struggling readers during crucial pre-school years, but the earlier the better," said Kraus, a professor of communication sciences, neurobiology and physiology in the School of Communication in a statement. "The challenge has been to identify which children are candidates for these interventions, and now we have discovered a way."

Source: Kraus N, et al. PLOS Biology. 2015.