Common and Unusual Traits of Autism (2024)

Autism spectrum disorder (ASD) is clinically diagnosed by specialists or teams of specialists who usually have significant experience. They use various tests to help determine if someone has ASD traits. Then they select one of three levels indicating the amount of support the autistic person needs, and they can select from a slew of specifications (such as intellectual disability) that may or may not be present.

But even all those tools don't provide enough information to help a parent, teacher, or therapist accurately envision a particular individual's strengths, challenges, behaviors, or needs. In fact, an ASD diagnosis tells you remarkably little about any individual person, their particular challenges and strengths, or the therapies that would help them cope with or overcome any difficulties.

This article discusses common traits of autism, as well as those seen less often in autistic people. It will help you to understand why some traits occur and what autistic people experience when navigating non-autistic society.

Universal Traits of Autism

People with an appropriate ASD diagnosis often share certain traits described in the American Psychiatric Association "Diagnostic and Statistical Manual of Mental Disorders Fifth Edition" (DSM-5). The diagnostic criteria for autism include the following:

• Difficulty with social communication and social interaction across multiple contexts
• Limited nonverbal communication and behaviors used for social interaction
• Challenges with developing, maintaining, and understanding relationships
• Repetitive patterns of behavior, interests, or activities
• Insistence on sameness, inflexible adherence to routines, or ritualized patterns of verbal or nonverbal behavior
• Intense, highly fixated interests or focus
• Overreaction to sensory input or unusual interest in sensory aspects of the environment, whether hyper (higher) or hypo (lower) in reaction.

Any of these traits can occur in someone who is not autistic, too. Autism is diagnosed, therefore, if all traits are present. In addition, the traits must not be explainable by another diagnosis.

For example, a person with differences in communicative behaviors may be hard of hearing or have low vision, either of which would impair verbal or written communicative skills. Finally, the traits must have a real and consistent impact on the person’s lived experiences and activities of daily life.

Autism Traits Can Be Hard to Identify

If you look closely at each of the autism traits, you'll recognize that they are very general. They also depend on a shared understanding of what is "normal," or neurotypical. The diagnostic criteria provide a range of possible ways in which the traits can present themselves, but even these don't begin to cover the full range of expression.

For example, all autistic people have difficulty with social communication and interaction. But how does that difficulty present? The possibilities are almost endless:

• An autistic person can be completely nonverbal and not use spoken language.
• They may be able to speak and write fluently but have a hard time recognizing sarcasm or jokes.
• They may be able to speak but only using phrases they repeat from TV or movies. They may be unable to craft their own unique phrases and sentences.
• They may be able to speak and write fluently but have an unusual "prosody" (flat or unusual vocal tone).
• They may be able to speak moderately well but use unexpected phrases that are unusual for their age or their situation (a 10-year-old using the term "indubitably," or an adult talking about a preschool television show).
• They may be able to learn to use new words and phrases at an unusually slow rate, or they may never learn to use new words or phrases at all.

The appropriate therapies and expected outcomes are very different based on not only the presentation but also the type of speech disorder.

Surprisingly, autistic people with lesser differences in communication may find it harder to manage in typical settings than people with more differences—because they are more aware of their challenges, of others' judgments, and of their social mishaps when they occur.

Well-Known But Uncommon Autism Traits

It's easy to think that unusual autistic abilities, behaviors, or interests are actually universal among autistic people. For better or worse, however, many of these are relatively rare.

The 1988 movie "Rainman" led many to assume that autism is characterized by outstanding feats of memory and calculation. This ability, called savant syndrome, is actually quite rare: Only about 10% of people on the spectrum have savant abilities. Of those, most (like the character in "Rainman") are unable to use those skills in real-world situations.

TV shows, documentaries, and media reports can suggest that autistic people have above-average intelligence, and many do. Yet quite a few autistic people also have intellectual disabilities with significant challenges in daily function.

It is a cliche that autistic people love and are good at technology. While there are certainly autistic people that fall into this group, a great many do not. In fact, lots of autistic people have little or no ability to code, operate complex software, or use household electronics.

Many sources show or describe autistic people as being able to think visually in complex ways. While most autistic people are visual thinkers, the ability to (for example) mentally manipulate three-dimensional objects is unusual.

Traits Shared By Non-Autistic Peers

There are many autistic traits that are shared by people who are not autistic. They become markers of autism based not on their existence but on the degree to which they vary from what non-autistic society considers neurotypical.

Of course, "normal" is in the eye of the beholder. Thus it can be hard to determine whether a behavior indicates a person is "autistic." To a degree, it's a matter of how the behavior is expressed rather than whether it is expressed.

Stimming

Stimming, which is short for self-stimulation, refers to sounds and movements that have no purpose other than self-calming or self-stimulation. These can range from the more common (hair twirling, toe-tapping, and nail-biting) to the less common, including:

• Swaying or rocking
• Continuous repetition of a phrase or song line
• Self-injury through headbanging or pinching

Most autistic people stim, but then again most human beings stim in one way or another. Most people learn, sooner or later, that while hair twirling is accepted in neurotypical society, rocking or twirling is not (though most children go through a stage during which they do a great deal of twirling). In response, autistic people either mask their traits or are unable or unwilling to conform.

Almost all forms of stimming are harmless and they offer benefits to the person stimming, but doing so is stigmatized and people with less-common forms of stimming are subject to teasing, bullying, stares, and marginalization.

Social Difficulties

If most non-autistic people were socially competent all the time there would be no such thing as self-help books, matchmaking services, romantic breakups, or divorce. In fact, reality TV shows would cease to exist.

Many non-autistic people have a hard time reading unspoken signals that say "I like you" or "I am romantically interested in you." What makes these qualities become autism traits, then, is not their existence but their quality and intensity.

Most non-autistic people can recognize a joke—based partly on their understanding of body language, partly on their understanding of human situations, and partly on their grasp of subtle differences that can make a situation funny. Autistic people may not recognize jokes at all or may have a very different idea of what's funny.

Sensory Dysfunction

If you've ever been overwhelmed by loud noise, bright lights, crowds, or even smells, you know what it's like to experience sensory overload. Sensory overload in autism is as a result of what most people consider to be common stimuli—that is, fluorescent light bulbs, emergency buzzers, crowded parties, and the like.

But many people without autism have similar issues, and some people (such as those who live with migraines or tinnitus) may have quite intense responses to sensory input without being autistic.

Autistic people may also be undersensitive to sensory input and crave loud noises or the sensation of being squeezed. Interestingly, weighted blankets, once considered to be therapeutic tools for people with sensory dysfunction, are now popular for those with mild anxiety, too.

Focused Interests and Behaviors

Intensely focused interests, behaviors, and routines are very common among autistic people—and among people in general. Autistic people may express this trait more intensely, for example, eating nothing but chicken fingers or becoming agitated when bedtime is pushed back by ten minutes.

But many autistic people are (or can be) as flexible as many non-autistic people who prefer sameness and routine. Similarly, it can be hard to distinguish between a neurotypical fascination with video games and an "autistic" fascination; the differences lie more in how the fascination is expressed than in the fascination itself.

That is: an autistic person may find it difficult to talk about anything except the favored interest, discuss the interest in a rapid monotone, and assume that others are as interested in the topic as they are.

Summary

It's important to remember that autism spectrum disorder is not a monolithic disorder; autistic people are as diverse as the non-autistic population. While some autistic people have traits that radically limit their ability to interact comfortably with non-autistic people, many do not.

What often differentiates the traits of an autistic person from the same traits in a non-autistic person is how they are expressed. And while some autistic people have rare savant traits, these are not typical of being autistic.

The bottom line, as is often stated in autism circles: "When you've met an autistic person, you've met an autistic person."