ADHD vs autism: how they overlap, differ and can go together

ADHD and autism overlap a lot on the surface: both can bring trouble with focus, sensory overload, social friction and big feelings. The difference is mostly in why. ADHD is mainly about regulating attention, activity and impulses, while autism is mainly about differences in social communication, a need for predictability and intense, focused interests. They can also go together, and since the DSM-5 diagnostic manual came out in 2013, clinicians can diagnose both in the same person.

What do ADHD and autism have in common?

Quite a lot, which is exactly why people wonder which one fits them. Both are neurodevelopmental conditions, meaning they’re differences in how the brain develops and works, present from childhood and lasting through life. Neither is caused by parenting, and neither is something you grow out of, though how they show up can change a lot with age and circumstances.

Things people with either can recognise include:

• Trouble with executive function: planning, starting tasks, switching between them, keeping track of time.
• Sensory sensitivity: noise, light, scratchy labels or crowded rooms can feel much louder than they seem to others.
• Social friction: conversations that go wrong, friendships that are hard to keep up, a sense of not quite fitting in.
• Intense focus: being absorbed in something for hours and struggling to come out of it.
• Emotional overwhelm: reactions that feel bigger or faster than the situation seems to call for, and needing time to recover.
• Exhaustion: from spending a lot of effort fitting into a world that wasn’t set up for how you work.

When you list traits like this, they look almost the same. The differences show up when you ask what’s underneath each one.

What’s the main difference between ADHD and autism?

The clearest difference is often how each relates to novelty and routine. ADHD tends to come with a hunger for stimulation: boredom is genuinely hard, new things are energising, and routines are hard to stick to. Autism tends to come with a need for predictability: change can be distressing, routines are calming, and a familiar interest is a comfort rather than a rut.

A rough comparison, with the caveat that people are individuals and plenty of them don’t fit neatly:

None of these rows decides anything on its own. Someone with ADHD can love routine, and an autistic person can be drawn to new things. It’s the overall pattern, over a lifetime, that a clinician looks at.

Why can social situations feel hard with both?

Because social life asks a lot of attention and a lot of intuition, and ADHD and autism each make one of those harder. The outcome can look the same, a conversation that went sideways, while the cause is quite different.

With ADHD, the problem is often keeping up. You might miss part of what someone said because your mind wandered, blurt something before thinking, interrupt because you’re afraid you’ll forget your point, or forget plans and seem like you don’t care. Most people with ADHD know what the social rules are. Following them in the moment is the hard part.

With autism, the problem is more often working out the rules in the first place. Autistic people often find it harder to read intentions, tone or what’s implied rather than said, and may prefer direct, honest communication. Small talk can feel pointless and tiring. Two of the statements in the autism screener get at this directly: finding it easy to “read between the lines”, and working out what someone is thinking or feeling just from their face.

Many autistic people, and many people with ADHD, learn to mask: copying others, rehearsing conversations, holding back fidgeting or strong reactions. It can work, at a cost. Masking for years is tiring, and it’s one reason both conditions are often recognised late, especially in women and girls. There’s more on that in the post about how ADHD shows up in women.

Can you have ADHD and autism at the same time?

Yes. Before 2013, the main American diagnostic manual didn’t allow both diagnoses together, so people who had both were usually given one label or the other. The DSM-5, published in 2013, changed that, and clinicians can now diagnose both in the same person. Having both is common enough that some people use the informal word “AuDHD” for it.

Living with both can feel like a tug of war. You might crave routine and find it impossible to keep one. You might need quiet and also get bored without stimulation. You might plan carefully because change upsets you, then lose the plan. People with both often say the two hide each other: ADHD’s restlessness can make you seem outgoing, covering the social effort underneath, while autistic structure can help you manage ADHD so well that no one looks closer.

If you’ve been diagnosed with one and parts of your experience still don’t fit, it’s reasonable to ask whether the other might be part of the picture too.

How do the ADHD and autism screeners differ?

They ask about different things, use different scoring, and look at different time frames. Neither one is a diagnosis. Each is a way to decide whether an assessment is worth asking for.

The ADHD screener (ASRS)

The ADHD screener uses six questions from the Adult ADHD Self-Report Scale, developed by Ronald Kessler, Lenard Adler and colleagues with the World Health Organization in 2005. It asks about the past six months: finishing the final details of tasks, getting organised, remembering appointments, putting off tasks that need a lot of thought, fidgeting, and feeling driven as if by a motor. Each question has its own threshold, and the result counts how many of the six reached it, from 0 to 6. A result of 0 to 3 is “Few signs”. A result of 4 to 6 is “Worth a closer look”.

The autism screener (AQ-10)

The autism screener is the AQ-10, a ten-statement version of the Autism Spectrum Quotient developed by Carrie Allison, Bonnie Auyeung and Simon Baron-Cohen at the Autism Research Centre in Cambridge in 2012. It asks about long-standing ways of noticing and thinking: small sounds, details, switching between tasks, collecting information about types of things, and reading other people. Each answer that leans towards the pattern common in autistic people scores a point, from 0 to 10. A score of 0 to 5 is “Fewer autistic traits”. A score of 6 to 10 is “Worth talking through”, the level at which UK guidance from NICE suggests considering a referral for a specialist autism assessment.

Where the two can blur

Because the conditions overlap, the screeners can too. A few AQ-10 statements, such as finding it hard to do more than one thing at once or to switch back quickly after an interruption, describe things many people with ADHD also struggle with. And the ASRS asks about organisation and getting started, which many autistic people find hard as well. So a high score on one doesn’t tell you which condition is behind it, and that’s fine: telling them apart is what a specialist assessment is for.

Should you take both tests?

If parts of both descriptions sound like you, taking both is a sensible idea. They take about five minutes together, and the combination can give a doctor a clearer starting point than either alone. If one comes back high and the other low, that’s useful. If both come back high, that’s useful too, and worth mentioning, because some services assess for ADHD and autism separately and you may want to ask how they handle both.

It’s also worth taking your answers with a pinch of salt in a stressful period. Anxiety, low mood, burnout and poor sleep can all push up answers about focus, organisation and feeling overwhelmed. The autism screener asks about long-standing patterns, so it’s less likely to move with your mood, but it’s still worth answering as you usually are, not as you feel this week.

What happens in an assessment for ADHD or autism?

A proper assessment for either is a careful look at your whole life, not a questionnaire. It’s done by a psychiatrist, a clinical psychologist or another specialist trained in the condition, and it usually includes a detailed interview about your childhood and how things are now. Clinicians often like to hear from someone who knew you when you were young, because both conditions start early.

Some things that help you prepare:

• Notes on what you’ve struggled with since childhood, with concrete examples.
• Your screener results, as a starting point for the conversation.
• Old school reports or memories from family, if you can get them.
• A sense of what you’re hoping to get out of it: understanding, support at work, treatment options, or all of these.

Your GP or family doctor is usually the first step and can refer you. If you’re diagnosed with ADHD, talk to your doctor about treatment options. Autism isn’t an illness to be cured, but understanding, support and adjustments at work or study can make a real difference, and so can treating anything that comes with it, such as anxiety.

What helps, whichever one it turns out to be?

A lot of what helps is the same, because it works on the shared struggles: overload, executive function and exhaustion. You don’t need a diagnosis to start.

• Lower the sensory load. Noise-cancelling headphones, softer lighting, a quieter seat. Small changes can leave more energy for everything else.
• Make plans visible. Calendars, timers and checklists help ADHD brains remember and help autistic people know what’s coming.
• Build in recovery time. After social events, busy days or big changes, plan a stretch with nothing in it.
• Watch for exhaustion. Many autistic people describe periods of deep exhaustion they call autistic burnout, after long stretches of masking and overload. It isn’t the same thing as work burnout, but they can feel similar, and the post on burnout warning signs may help you notice when you’re running low. If tiredness is constant, it’s worth checking the other reasons you might feel tired too.
• Drop the self-blame. Years of being called careless, rude or too sensitive leave a mark. A short self-compassion pause can soften that on hard days.

Anxiety often comes along with both conditions, sometimes as a result of years of trying to keep up. If you look calm on the outside and feel anything but, the post on anxiety that hides behind getting things done may sound familiar.

Where to go from here

If you recognise yourself in one side of this more than the other, start with that screener. If you recognise both, take both: the six-question ADHD check and the ten-statement autism check together take a few minutes. Then take your results, and a few real examples from your life, to your doctor. The labels matter less than what they open up: a clearer understanding of how you work, and support that fits it.