In 2015, we live in an age where autism is diagnosed more frequently than ever—at a rate of 1 in 68 children in the U.S.—which means that more people are aware of the condition than ever before. However, the rate of diagnosis and general understanding of autism was but a minute fraction of what it is today prior to the 1990s. So why were cases of autism so hard to discover before the 1990s?

This is the question at the heart of Steve Silberman’s new book—as well as his March 2015 TED Talk about “the forgotten history of autism”—entitled Neurotribes: The Legacy of Autism and the Future of Neurodiversity. According to Silberman, unlike polio or the measles, autism as a condition and a diagnosis has failed to follow the path science or personal experience has carved out for it.

Or as Silberman himself puts it, “I learned that what happened has less to do with the slow and cautious progress of science than it does with the seductive power of storytelling.”

Silberman starts his story with Leo Kanner, a child psychiatrist who in the 1940s published a case study depicting eleven boys who demonstrated certain abnormal characteristics, such as flapping and anxiety surrounding changes to routines. As Silberman recounts, Kanner was protective of his findings and discouraged the autism diagnosis in people who had seizures, although we now know seizures can be common in people with autism.

In spite of Kanner casting an aura of rarity around the condition that would be called Autism, with only 1 in 2500 people being diagnosed in 1985, by 1995 that rate had increased to 1 in 500. Silberman is quick to point out that this increase is a severe departure from Kanner’s assertions that Autism is a rare condition and the vast increase in diagnoses has led some people to erroneously refer to autism as an epidemic.

However, it might have been Kanner’s own behavior that has led to this precipitous change in perception as he was known to turn away nine out of ten children from his practice because he diagnosed Autism so infrequently and undiagnosed many of the patients that were referred to him by other doctors.

So what role did Kanner’s ownership of the diagnosis of Autism have in shaping the public’s perception of Autism and how much responsibility does he shoulder for the many people with Autism who existed either undiagnosed or diagnosed with another condition? As Silberman notes, it played a huge role in convincing people that Autism was far more rare than it actually was and he also was incorrect in citing environmental factors, like parents, as the cause of autism.

While Silberman paints a frustrating portrait of how the belief of one man shaped decades of autism understanding, he also holds hope for the future, stating “To be sure, people with Autism have a hard time living in a world not built for them. [Seventy] years later, we’re still catching up to (Hans) Asperger, who believed that the “cure” for the most disabling aspects of autism is to be found in understanding teachers, accommodating employers, supportive communities, and parents who have faith in their children’s potential.”

So we as a culture align our perceptions of Autism with what science has proven so far, ultimately greater understanding of the condition and showing support for those who need it are our best bets for advancing our cultural relationship with Autism.