Jack Craven has superpowers. When his mother, Lori, misplaces an item in the house, she asks the 12-year-old to “look in your head,” through the rich catalog of visual information he seems to assemble without effort. Jack always finds the lost object. His astonishing memory for faces enables him to pick out someone he’s seen only once or twice before from a sea of strangers in a crowded school gymnasium. His sharp hearing makes him an excellent vocal mimic. Request that he sing a Beatles tune and he’ll ask if you want it sung in the style of Lennon or McCartney.

But great powers, as any superhero narrative goes, come with great challenges. He endures, rather than enjoys, the arcade birthday parties popular among tween boys in suburban Atlanta where he lives. They’re just too noisy, too busy, too overstimulating. Jack’s hearing is so sensitive that he can’t always eat at the table with his family, because the sound and sight of them chewing might make him throw up. As an infant, he never slept for more than four hours at a stretch, and had to be held upright the whole time, his stomach pressed against his mother’s chest and her palm pressed atop his head.

Jack has sensory processing disorder (SPD), a condition that includes people who are overly sensitive to what they feel and see and hear, but also those who are undersensitive, and still others who have trouble integrating information from multiple senses at once. SPD is not an official diagnosis. It isn’t included in the newest edition of the “Diagnostic and Statistical Manual of Mental Disorders” (DSM-5). Still, it is widely used as a catch-all by clinicians, and some studies suggest that it may affect between 5 and 15 percent of school-age children. Children with the clinical label SPD also have a lot in common with children diagnosed with autism, up to 90 percent of whom also have sensory difficulties.

Jack doesn’t have autism, but Ari Young, who lives a few hundred miles away in North Carolina, has both SPD and autism. And Ari, too, has certain impressive abilities, thanks to his super-sensitive senses. His acute visual memory allows him to recite articles from Wikipedia nearly verbatim — although, unless the article is on a history- or science-related topic he’s particularly interested in, he may be able to recall the information only in the order in which he learned it. Ari’s mother, Heather McDanel, says his sensory peculiarities and his autism are all bound up together. With many of his idiosyncrasies, “I don’t know if that’s the autism or if that’s sensory, or a combination of the two,” she says.

Like Jack, Ari also had sleep-related quirks as an infant: He could drift off only while rocking in a baby swing to a recording of birds chirping, and his bleary parents had to restart it every 15 minutes throughout the night. A speech therapist first mentioned SPD when Ari was not yet 2 years old; the autism diagnosis came later, when he was 2 and a half.

Even today, at age 9, Ari tends to hum to himself either when it’s too quiet or to drown out noise. He attends third grade in a mainstream classroom, but his sensitivities sometimes make school a struggle. A few months ago, when an unexpected announcement that class would be dismissed early caused his fellow students to erupt into happy chaos, the hubbub sent Ari running, sobbing with confusion and surprise, to the front office.

Sensory problems can not only disrupt a child’s ability to learn in school and form friendships, but upend the lives of whole families. “These are really challenging kinds of problems for children, whether they’re diagnosed with something or not,” says Grace Baranek, professor of occupational science and occupational therapy at the University of North Carolina at Chapel Hill. And for families, it can be difficult to get help.

Yet SPD also offers an opportunity: Studying people who have sensory problems with or without an autism diagnosis could help these children and provide insight into the relationship between sensory problems and the core social and communication problems seen in autism. It’s easy to imagine that a young child who hardly registers the sights and sounds of the surrounding world may not tune in to her father’s games of peekaboo, and may miss out on these formative moments of communication. Meanwhile, a child for whom those sights and sounds are unusually intense may be too overwhelmed to focus on his mother’s attempts to catch his attention and never learn some of the subtleties of the social world.

In the past several years, the advent of more precise, objective ways to measure sensory responses and behavior, coupled with imaging techniques that pinpoint how the brain processes sensations, are providing a window into how this process goes awry — and perhaps, ultimately, how to get it back on track.