The 9 Biggest Signs Of Autism In Adulthood

Internally, many undiagnosed adults with autism say they feel different from those around them.
Internally, many undiagnosed adults with autism say they feel different from those around them.

Internally, many undiagnosed adults with autism say they feel different from those around them.

You may have seen videos on social media where people detail the signs that made them realize they’re autistic. Viewers are finding them enlightening and comforting as many people  — mainly women — are undiagnosed as they reach adulthood.

According to Dr. Megan Anna Neff, a clinical psychologist based in Oregon, a recent study found that 80% of women with autism are still undiagnosed at age 18.

There are many reasons for this: For starters, people learn to adjust their behavior to fit in with society. Additionally,the autism diagnostic tools used today were developed exclusively on white boys from high socioeconomic status, said Stephanie Gardner-Wright, a licensed master social worker and certified autism clinical specialist in Michigan.

There is also a huge focus on the external signs and not so much the internal symptoms of autism, Gardner-Wright said. And those internal symptoms are very different from person to person.

“There are so many ways that autism can show up and present,” Neff added. “I think there’s more diversity within autism than there is between autism and allistic.” (Allistic people are folks who aren’t on the autism spectrum.)

That said, there are a number of signs or thought patterns that undiagnosed autistic people may be able to relate to. HuffPost spoke with mental health professionals, including some people who are neurodivergent themselves, about the signs of autism in adulthood:

A Feeling Of Being ‘Different’ From Others

All four experts shared that it’s common for autistic people to feel different. Brandon Tessers, the director of Effective Artistry, a therapy group that supports neurodivergent people, said some folks will describe it as “feeling like an alien sometimes,” while Dr. Vanessa Bal, the director of the Center for Adult Autism Services Psychological Services Clinic at Rutgers University in New Jersey said folks describe it as “a lifetime experience of feeling different.”

The difference between this feeling and the occasional outsider feeling everyone deals with from time to time is that for autistic folks, this feeling does not come and go and is not only during one specific period, like middle school, Bal told HuffPost.

Gardner-Wright added that this is a big indicator and an internal experience at that — you cannot look at a person and know if they feel like an outsider. The feeling could be overpowering or could be more subtle, it depends on the person, she said.

But, it’s important to know that autistic people don’t necessarily feel like outsiders all the time, Bal noted. They may find settings that are more inclusive for neurodivergent people. Additionally, some adults also say they feel more comfortable with who they are and worry less about differences, sometimes seeing them as strengths, as they get older, Bal said.

Difficulty With Social Cues

Social cues are also another sign. Someone with undiagnosed autism may find they have trouble deciphering how much eye contact is appropriate or when they should stop smiling during a conversation, Gardner-Wright said. They may be able to mask these uncertainties by learning how much is appropriate, but it’s not an innate sense as it is with someone who is allistic, she added.

A Confusing Relationship History — Both Romantically Or Platonically

According to Neff, many undiagnosed autistic adults have a confusing and complicated social relationship history. Additionally, romantic relationships may feel tough to navigate.

“There might be relationships that have that kind of suddenly burst apart but the autistic person doesn’t understand why,” she said. When it comes to the reason behind this complicated relationship history, it’s likely that the person with autism doesn’t know why their relationships fail when other people’s don’t.

Sensory Differences

Sensitivity to sensory input — like noise and sight — is another potential sign of autism, said Gardner-Wright, who added that this can mean being hyper-aware of a sound or totally unaware.

People who are not autistic tend to be more or less responsive to sensory stimuli, she said.

For example, an autistic person may find that they’re constantly aware of a ticking clock at a friend’s house or really sensitive to the sound of a loud siren, Gardner-Wright noted.

A Desire For Routine

Many people with autism thrive on consistency. “The world we occupy is much more uncertain and unpredictable. So we go to routine as a way of self-soothing,” Neff said. When a routine is disrupted, strong emotions may present, including intense irritability or anxiety.

Gardner-Wright added that the routine doesn’t need to be super strict, either; it’s a common misconception when people think about people with autism’s day-to-day schedule. Instead, it could be a strong preference for a certain mug every morning. Routine looks different for different people.

Additionally, big changes can be hard, too. “If they move [homes] or they move careers, this could create a season of insomnia or anxiety,” Neff said.

Routine can extend to certain behaviors as well. It also includes repetitive body movements, which is known as stimming, Neff added. According to the Children’s Hospital of Pennsylvania’s Research Institute, stimming behaviors can include body rocking, hand flapping, spinning, rubbing a specific surface and squealing.

A Need For Solitude 

Another common sign? “Needing solitude to recharge after social situations or really overstimulating situations — and overstimulating could be different for everyone — but that is a very typical hallmark of [autism],” Gardner-Wright said. This could mean feeling totally exhausted after a work presentation or a family party.

Bal said this exhaustion comes from a term known as “camouflaging” or “masking.” “This is the idea that you have to really hide different facets of yourself or different behaviors in order to fit in what you think the expectations around you are.”

And while we all do this at times, the degree that autistic people have to camouflage aspects of themselves may results in a feeling of total drainage where afterward they report spending long periods of time alone or in dark and quiet places to recover, Bal said.

Tessers added that, from the outside, people have no idea when someone is camouflaging. “They’re doing what everybody wants or expects of them to some successful degree.” This could look like behaving as you “should” at work but going home and crashing and dreading the idea of having to do this camouflaging all over again tomorrow, Tessers noted.

It's not uncommon for an adult with autism to need time alone after days filled with social commitments.
It's not uncommon for an adult with autism to need time alone after days filled with social commitments.

It's not uncommon for an adult with autism to need time alone after days filled with social commitments.

More Intense Interests

A deep curiosity and passion for one particular activity or subject can also develop. “Our brains tend to gravitate with a lot of passion towards our area of interest and we become very invested in them and it’s also a way we self-soothe,” Neff said. This could mean building a career around a specific interest or knowing everything about a specific hobby.

And while everyone has interests — and many people have strong interests — Neff said autistic folks likely find a way to relate everything to their specific interest. For example, this could look like finding a way to talk about a favorite TV show even when the conversation revolves around current events.

“Allistic people can have a special interest but then it doesn’t become their lens for their whole world,” Neff said.

A Dislike Of Small Talk

Most people don’t love small talk, but for people with autism, small talk can feel totally exhausting or something that shouldn’t have to happen.

“They typically don’t enjoy small talk and perhaps found ways to avoid it,” Neff said. “Maybe they structured their life or their career in a way that they don’t have to do a lot of that allistic communication.”

Gardner-Wright added that people who are on the spectrum tend to prefer deep, meaningful conversations.

A Desire For Direct Communication

People with autism thrive on straightforwardness, with “really honest, clear communication being a strong preference,” Gardner-Wright said.

Neff said autistic people tend to be pretty literal. For example, when you say the phrase “it’s raining cats and dogs,” she said autistic people may picture literal cats and dogs falling from the sky in their mind, but then realize the person speaking is referring to rain.

“So, actually, I think it’s perhaps more precise to say we’re visual in our communication style versus literal, but it often shows up as being literal,” Neff said. Additionally, the communication style can be described as direct and honest. “What we say, we tend to say at face value,” Neff added. 

If you think you have these signs, look to autistic voices for guidance.

Both Gardner-Wright and Neff recommend exploring the hashtag #actuallyautistic on social media to listen to lived experiences and hear from people in your specific community about how this exists for them.

“Discovering that you’re autistic as an adult can be really validating,” Gardner-Wright said. It can help you more fully understand yourself and your life. “But there can also be a grieving process for that,” she said, where you may wish you had this information when you were a kid so certain situations could have been different.

“Feeling a mix of grief and also excitement is very, very normal,” Gardner-Wright said.

Additionally, is a helpful resource for free screening tools and tests to help you understand if you are autistic — though it is not diagnostic, they’re simply online guides to help arm you with information, Gardner-Wright noted.

You can reach out to mental health professionals, too.

Neff said it can be helpful to connect with a therapist to talk about this new discovery, but she stressed that it’s important to find one who is neurodivergent-affirming or -informed.

Bal agreed and said “we have a long way to go with respect to training medical professionals and mental health professionals about autism. I worry there’s a lot of misinformation and misconceptions out there.”

Bal added that you can also look up autism centers near you for diagnosis or treatment, but noted that many have a yearslong waitlist and may focus only on children. If they can’t fit you in, Bal said, you can ask if they have resources they recommend, or look for community autism organizations to see if they have any resources.

Additionally, a community of supportive people can be helpful as well, which is where the #actuallyaustic hashtag — or other online communities — can be helpful.