The autism spectrum isn’t a sliding scale; 39 traits show the complexity

Autism is a spectrum. This metaphor is a helpful way to explain why autism looks and feels so varied across different people. Since 2013 it’s been baked into the name of the diagnosis itself, autism spectrum disorder (ASD). But what does this spectrum look like?

It’s not simply a one-dimensional scale from “more autistic” to “less autistic,” which would collapse so much of the diversity that the spectrum metaphor is meant to showcase. There is no single trait that defines autism: it encompasses differences in social communication skills, interests, sensory sensitivities, and more. Every person’s profile is unique. These graphics, based on clinicians’ evaluations of actual people using the Autism Symptom Dimensions Questionnaire, reveal a more nuanced “spectrum” of differences.

And this picture doesn’t factor in how people’s profiles change over time in response to treatments, life circumstances or age. It also doesn’t measure individuals’ overall cognitive ability, something researchers treat as a separate but important feature that can affect someone’s particular constellation of traits.

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Not all these characteristics are impairments that should be treated. “Someone not making eye contact is useful information for diagnosing autism,” but it is not necessarily an appropriate target for intervention, says Ari Ne’eman, co-founder of the Autistic Self Advocacy Network and a health policy researcher at Harvard University. Many of these traits are best thought of as normal human variation rather than something to be treated or changed, Ne’eman says.

A spectrum in many dimensions

Each of the 39 wedges in the circle represents one question in the Autism Symptom Dimensions Questionnaire. The traits associated with each question (listed below) are grouped into key symptom factors—the main aspects of behavior that evaluators look for when they assess someone for autism.

Variation across individuals

These charts represent questionnaire responses for three different autistic individuals. These data reflect each person’s strengths and challenges at their current stage of development and may change over time.

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