When 7-year-old Mia hears a sentence, her brain processes every sound clearly. But another child with autism might hear the same words through a kind of static, making it harder to pick out what matters. Now, researchers think they know why — and it comes down to patterns of electrical activity deep inside the brain.

Scientists at the University of Virginia have discovered that subtle differences in brain signals while children listen to speech are connected to how well autistic youths communicate in everyday life. Their study, published in the journal Scientific Reports, analyzed brain activity in 306 children and teenagers, ages 7 to 18, including 162 youths with autism and 144 typically developing peers.

To measure brain activity, researchers outfitted each participant with a special cap fitted with 128 sensors — essentially a detailed map of the brain's electrical chatter. While the children listened to streams of nonsense words designed to test how the brain processes speech, the caps recorded what was happening inside.

The team focused on something called the brain's "aperiodic" signal, which acts like a volume dial between two opposing forces: excitation and inhibition. Think of it like a radio tuning out static to hear a station clearly. The researchers found that autistic participants showed altered patterns in these signals, with more neural "noise" — suggesting their brains may struggle to separate meaningful speech from background chatter.

Here is what made the discovery especially useful: the children whose brains appeared noisiest also scored lower on tests of everyday verbal communication — things like having conversations or responding appropriately in social situations. But the brain signals had no link to traditional language skills, such as vocabulary or grammar. That matters because it means this marker specifically measures how autism affects real-world communication, not just how well someone knows words.

"This is an important step toward understanding the neural mechanisms underlying communication in autism," said Kevin Pelphrey, a neuroscientist at UVA and co-author of the study. "If we can identify reliable biological markers, they could eventually help researchers evaluate interventions more objectively and understand why communication abilities differ so widely across the autism spectrum."

The researchers stress this is not a diagnostic test for autism — the brain patterns were linked to communication ability, not autism itself. But the findings point toward a promising tool for tracking changes over time and measuring whether therapies are actually working at the brain level.

The study also highlights how powerful computers are helping scientists find patterns in brain data that were previously invisible. Jack Van Horn, a professor in UVA's School of Data Science and co-author, put it this way: "The human brain generates an incredible amount of data every second. The challenge isn't collecting it anymore; it's making sense of it. Advances in computational analysis are allowing us to separate meaningful signals from background activity in ways that weren't possible just a few years ago."

More research is needed before these findings can be used in clinics or therapy settings. But for the estimated one in 36 children diagnosed with autism in the United States, this study offers something rare: a clearer picture of why communication can be harder for some, and a new way to think about helping.