The autism spectrum is not a sliding scale; 39 properties show the complexity

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

It’s not just 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 characteristic that defines autism: it encompasses differences in social communication skills, interests, sensory sensitivities and more. Each person’s profile is unique. This graphic, based on clinicians’ ratings of actual people using the Autism Symptom Dimensions Questionnaire, reveals a more nuanced “spectrum” of differences.

And this picture does not take into account how people’s profiles change over time in response to treatments, life circumstances or age. Nor does it measure individuals’ general cognitive ability, which researchers treat as a separate but important function that can influence someone’s particular constellation of traits.

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Not all of these characteristics are impairments that should be treated. “Someone not making eye contact is useful information for diagnosing autism,” but it’s 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, says Ne’eman.

A spectrum in many dimensions

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

Variation across individuals

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

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