The Centers for Disease Control and Prevention estimates that one in 68 children in the US are on the autism spectrum, a number that stands in staggering contrast to a 1970 study that put the figure at one in 14,200. Some people believe we're in the middle of an autism epidemic. But autism has always been part of the human experience, as journalist (and WIRED contributor) Steve Silberman shows in his new book, NeuroTribes: The Legacy of Autism and the Future of Neurodiversity. It's only recently, he argues, that we have become properly aware of it. We spoke to Silberman about how the modern world came to recognize autistic people and how autistic people helped shape the modern world.

WIRED: In your book you write about Austrian pediatrician Hans Asperger, who did early work on autism in the 1930s. Why is he so important?

SILBERMAN: The more that I discovered about Asperger's conception of autism, the more it struck me as incredibly prescient. He saw autistic people as a subset of humanity that had accelerated the evolution of science and technology. They were a hidden thread in the weave of culture. They had always been here. Asperger conceived of autism as a condition that lasted from birth to death. It was not just a childhood disorder.

And yet he didn't get credit for discovering autism. This guy Leo Kanner, who wrote a paper that came out in 1943 in English, got nearly all the credit for discovering it, and Asperger was reduced to a footnote.

How did Kanner's and Asperger's concepts of autism differ?

Kanner's conception of autism was much more limited—he saw it as a rare form of childhood psychosis. Eventually, by 1948, he had decided it was caused by bad parenting—refrigerator mothers.

That had huge effects on the history of autism. Autistic children were dumped in state institutions. They did very badly, and that became what people thought was the natural course of autism. Being diagnosed with autism was considered a fate worse than death. Autistic people became invisible—not only because the kids were in institutions but also because the parents were being blamed for having caused the disorder.

So Kanner's rigid definition of autism helped create the impression it was extremely rare?

Yes. And it became a self-fulfilling prophecy: Kanner once bragged he turned away from his office nine out of 10 children who were referred to him as autistic by other clinicians, without giving them an autism diagnosis. Now you have a whole infrastructure of clinicians who are qualified to diagnose autism. Teachers know what to look for. Parents know what to look for. Everybody's looking at young children to see if they're autistic or not. Whereas back then, all you had was Leo Kanner's office.

So how did the rediscovery of Hans Asperger—and the naming of Asperger's syndrome in his honor—come about?

In the 1970s, a cognitive psychologist in England named Lorna Wing and her research assistant, Judith Gould, went out to do something that should have been done 30 years earlier—they looked at autism in the general population. They pounded the pavement in this London suburb called Camberwell, looking for autistic kids. Basically, they found that there was a broad and diverse and colorful range of presentations of autism and autistic traits in the kids. Kanner's definition was obviously too narrow, so they decided to throw it out.

Then Wing read a paper citing Asperger and said, “What is this other paper?”1 Her husband spoke German, so he translated for her, and she said, “This is it. This is what we're seeing in Camberwell.” So what they did was quietly work with the American Psychiatric Association to change the diagnosis to reflect the broad and diverse reality of autism.

When you see that history laid out, it's no surprise that the estimates of autism rates went up in the 1990s. They now included conditions on the autism spectrum, like Asperger's and “Pervasive Development Disorder Not Otherwise Specified.” Why did so many people mistake a change of diagnosis for an “autism epidemic”?

It was really a science communication issue. The people who knew what was going on, like Lorna Wing, were this tiny little circle of experts who were all talking to each other in scientific journals.

Once the diagnoses started going up, the really gripping stories were “Oh, there's an autism cluster in this polluted town in Massachusetts.” 20/20 started claiming the town was having an autism epidemic. Once epidemiologists went into the town, they saw, well, no, there was nothing like that going on. It was likely just that more kids were getting the Pervasive Development Disorder Not Otherwise Specified diagnosis, which was still new. But once it turned out to be a more complicated situation, the networks would not retract their stories.

You write about how the iPad is just the latest in a long string of technologies that have helped autistic people connect with others—likely starting with ham radio in the early 1900s.

They could use the equipment to communicate. They didn't even have to talk—they could use Morse code. So they could socialize in a way that was comfortable for them.

The iPad turned out to be a boon, because specialized communication devices for autistic children were always incredibly expensive and inflexible. The iPad comes along and it can be that communication device.

How are autistic people using iPads?

Many autistic kids are more comfortable with icons than with language. They press an icon on the screen and the iPad will talk for them. It's an example of how you can improve the quality of people's lives by providing them with new avenues for communication.

As autistic people gain the ability to speak for themselves, many of them are calling for thinking about autism as one dimension of what they call neurodiversity. What does that term mean?

One way to understand it is to think of human operating systems. Just because a computer is not running Windows does not mean it's broken. It's doing things in different ways. Autistic people are bad at reading social signals but good at detecting flaws in visual patterns. They have a hard time coping with surprise, but they're good at pursuing a personal interest with great focus and intensity. So instead of diseases and cures and causations, we should think of autism as a different way of being that deserves respect and accommodation in society.

But what about someone who is nonverbal and is violently banging their head against a filing cabinet?

Instead of thinking of someone who can't talk as a hopeless case, neurodiversity would say, “Let's look for ways to help them communicate.” It turns out many, many autistic people who are nonverbal are incredibly intelligent. But they need some technological help to articulate their thoughts.

If we're able to improve communication, we might discover that the kid is not hitting herself because she has autism. Maybe the hum of the fluorescent light is driving her crazy. Unless you strive to open a channel of communication with the kid, you'll never understand.

Carl Zimmer(@carlzimmer) is the author of 12 books. He wrote about gene therapy in issue 21.08.

1 UPDATE 10:05 AM PT 08/20/15 A previous version of this story misattributed Lorna Wing's discovery of Hans Asperger to a paper by Leo Kanner.