Autism

What it's like

From the inside, the signs at each age, and how autism can hide.

From the inside

• Too much at once: Everyday sounds, lights and textures can be overwhelming, and the brain's alarm doesn't settle with repetition.
• Eye contact: Can feel invasive, even physically uncomfortable.
• Stimming: Movement that helps regulate — and the main problem with it is other people's reactions.
• Deep interests: A real source of wellbeing.
• Masking: Hiding differences to fit in, which is exhausting.
• Naming feelings: About half of autistic people find it hard to identify their own emotions.
• Not knowing: Uncertainty and sudden change drive much of the anxiety.

Autism shows up in two areas: social communication and interaction, and restricted or repetitive behaviours and interests — including unusual reactions to sounds, smells, tastes, sights or textures. Most autistic people have some of the signs below, not all of them.

Social signs in young children — what may not have happened yet

• By 9 months: Responding to their name, or showing basic facial expressions.
• By 12 months: Simple games like pat-a-cake, or gestures like waving.
• By 15–18 months: Pointing to show you something interesting.
• By 24 months: Noticing when someone else is hurt or upset.
• By 36 months: Joining other children in play.
• By 48 months: Pretend play.

Repetitive behaviours and interests

• Lining things up, and getting upset when the order changes.
• Repeating words or phrases (echolalia).
• Playing with toys the same way every time, or focusing on one part of an object.
• Being upset by small changes; intense interests; needing routines.
• Flapping hands, rocking or spinning.
• Strong reactions to sounds, smells, tastes, sights or textures.

Autism can hide

Many autistic people camouflage — copying others and hiding their differences to fit in — and say it's exhausting. Girls who meet the criteria are especially likely to go undiagnosed. Long-term stress without support can lead to autistic burnout: exhaustion, losing skills, and less tolerance of noise and light.

• Myth: Vaccines cause autism. In fact: In 657,461 Danish children, the MMR vaccine didn't increase the risk of autism, didn't trigger it in children at higher risk, and wasn't followed by any cluster of cases.
• Myth: Autistic people don't have empathy. In fact: About half of autistic people find it hard to identify their own emotions, against about 5% of others — which isn't the same as not caring. Misunderstanding runs both ways: autistic people pass information to each other as well as non-autistic people do, and it's mixed groups where it breaks down.
• Myth: There's an autism epidemic. In fact: In Denmark, changes to how autism is diagnosed and recorded explained about 60% of the rise.
• Myth: It's caused by parenting. In fact: In over 2 million children from five countries, autism was about 80% heritable.
• Myth: She can't be autistic — she's chatty and does well at school. In fact: Girls are disproportionately likely to be missed, and many autistic people mask their differences in public at a real cost.

What's different in the brain

Less filtered, more detailed, and an alarm that reacts to what others tune out. The model lights each one as you read.

Sensations that don't fade

In autistic young people who find everyday sensations overwhelming, the hearing and touch areas responded more strongly to mildly unpleasant sounds and textures — and the amygdala reacted more, and didn't settle when the same thing happened again. More than half of autistic young people find some everyday sensations overwhelming.

Detail first

During visual tasks, autistic people show more activity in the brain's visual and perceptual areas and less in the frontal cortex. Many perceive fine detail especially well. One influential theory is that autistic perception leans less on expectation, taking the world in more as it is — still being tested.

Why eye contact can hurt

When autistic people were made to look at the eyes in a face, a fast, deep face pathway including the amygdala lit up unusually strongly. Autistic people describe eye contact as invasive, even physically uncomfortable. Looking away can be how they manage to listen.

Interests that matter

Shown things connected to their own interests, autistic children's brains responded more strongly in the insula and anterior cingulate, areas tied to feeling. Deep interests go with higher wellbeing in autistic adults.

Why it happens

Mostly genes — and why the numbers have risen.

• ~80% heritability: In more than 2 million children across five countries.
• 1 in 31 eight-year-olds: Identified as autistic across 16 US monitoring sites in 2022.
• ~3:1 boys to girls: Closer to 3 to 1 than the 4 to 1 often assumed.

Autism mostly comes through genes. It isn't caused by vaccines or by parenting. The numbers have risen mainly because of how autism is diagnosed and recorded — about 60% of the rise in one Danish study.

Getting an assessment

Screening, diagnosis, and what to do if you're an adult who wonders.

How it usually goes for a child

1. Screening at check-ups: Every child should be screened for autism at 18 and 24 months, alongside general developmental checks at 9, 18 and 30 months.
2. A positive screen isn't a diagnosis: Screening tools can't diagnose; a positive result should lead to a thorough assessment.
3. The assessment: By an experienced professional — and by age 2, their diagnosis can be considered very reliable.

Autism can be diagnosed at any age. Diagnosing adults is often harder, but an adult who wonders can ask a doctor for a referral to a psychologist, psychiatrist or neuropsychologist with autism experience.

Worth bringing

• Notes on the milestones above — what happened, and when.
• Videos of the behaviour you're wondering about.
• What school or nursery has noticed.
• What's hard for your child at home after school — not just what's hard at school.

What helps

Not a cure — support for communication, for the senses, and for everything that comes alongside.

What a support plan can include

• Speech and language therapy, occupational therapy, physical therapy, and educational support.
• Behavioural and psychological therapies.
• Medicines for specific difficulties — anxiety, irritability, attention, hyperactivity — though not for autism itself.

• Early, play-based support (Developmental and naturalistic approaches that build communication through play and everyday routines.): In randomised trials these were the approaches with positive effects — but when only outcomes measured without bias were counted, no approach showed clear effects. Promising, not settled.

A lot of what makes life hard comes alongside autism rather than from it. About 28% of autistic people also have ADHD, 20% an anxiety disorder, 13% a sleep disorder and 11% depression — and each of those has treatments that work.

Adjustments that follow from the evidence

• Predictability: Warnings before changes, visual schedules, plans written down. Intolerance of uncertainty explains much of the link between autism and anxiety.
• Less sensory input: Ear defenders, sunglasses, quiet spaces, softer clothes. Sensory differences are a core part of autism, and everyday sensations overwhelm many autistic young people.
• Room to recover: Time and space after a day of holding it together, before burnout sets in.

Situations you'll recognise

Moments that are often misread — what's going on, and what helps.

Supporting someone

Small changes that make the world easier to live in.

• Instead of "Look at me when I'm talking to you.", try "You don't need to look at me — I just need to know you're with me.". Autistic people describe eye contact as invasive and overwhelming. Looking away is often how they listen.
• Instead of "Stop flapping — people are staring.", try "(Nothing. Let them.)". Autistic adults describe stimming as a way of regulating themselves; its main problem is other people's reaction.
• Instead of "It's only a small change — don't make a fuss.", try "Heads-up: after school we're going to Grandma's, not home. We'll be back by six.". Uncertainty drives much of the anxiety autistic children feel. A warning and a plan take most of the sting out of a change.
• Instead of "You don't seem autistic.", try "Thanks for telling me. What helps you?". Seeming fine is often camouflaging — and camouflaging is exhausting.

Day to day

• Give warnings before changes, and show plans visually where you can.
• Have a quiet place to retreat to — at home, and agreed at school.
• Treat deep interests as a strength: they go with higher wellbeing.
• Expect a crash after a day of holding it together, and leave room to recover.
• Say what you mean, literally; check what's been understood.

When to get help

When to ask for an assessment — and when something else may be going on.

Ask for an assessment if…

• Your baby or toddler isn't reaching the social milestones above — responding to their name, pointing, joining in play.
• Your child's play, interests or reactions to sounds and textures worry you.
• A school or nursery raises concerns.
• Your child copes at school but falls apart at home, every day.

Watch for anxiety and depression

Anxiety and depression are common in autistic people — around 20% and 11% respectively — and burnout can follow long periods of masking without support. They're treatable, and worth getting help for in their own right.

If someone might be in danger

If an autistic child or adult talks about wanting to die or to hurt themselves, take it seriously and get help today. Asking directly about suicide doesn't put the idea in their head.

Put it into practice

Five real situations. Choose what you'd do, and see why.

• Your 18-month-old doesn't point to show you things, rarely turns when you say his name, and isn't babbling much. Your relatives say boys talk late. What's the best next step? Mention it at his check-up and ask for autism screening. Not pointing by 15–18 months and not responding to his name are recognised signs, and every child should be screened at 18 and 24 months.
• You're 27. You've always copied how other people act to fit in, you're exhausted after every social event, and noise and bright lights wear you down. You're wondering if you might be autistic. What's true? It's worth asking for an assessment — masking and sensory overload are common in autistic adults. Camouflaging to fit in is common and exhausting, sensory overwhelm is a core part of autism, and adults can ask for a referral to an experienced psychologist or psychiatrist.
• A relative says your nephew's autism was caused by his MMR jab and is urging you not to vaccinate your baby. What does the evidence say? MMR doesn't cause autism. In 657,461 Danish children, MMR vaccination didn't increase autism risk or trigger it in susceptible children. Autism is mostly genetic.
• At a concert, your autistic friend suddenly goes quiet, covers their ears and stops answering you. What helps most? Go somewhere quieter with them, keep words few, and let them recover. For many autistic people everyday sound is overwhelming, and reducing the input is the most direct help.
• Your 14-year-old spends hours on trains — timetables, models, videos. A relative says to ban it until her grades improve. What's the evidence? Protect it, and use it — while keeping an eye on balance. Special interests go with higher wellbeing and life satisfaction, though very intense engagement can tip the other way.