John Wemmie, a neuroscientist at the University of Iowa, says that while the findings of Miyakawa’s group are intriguing, “it's tissue after the animals or the humans have died, so it's hard to know if that's related to the pH changes [in the living brain].”

Each morning, Katie woke up and began playing with her dolls. She didn’t talk; she just played—for hours on end. And when her parents interrupted, the five-year-old often became angry and destructive. Katie has autism, and her parents, who live in a small western Iowa town, are 90 miles from the closest behavioral services. In desperation, they signed up for a University of Iowa study that connected them to video coaching they could use to better manage their daughter’s frustrations.