Last updated August 26 2024 | by Iain Dolan, autistic psychologist

Autism is often stereotyped as a condition characterized by “severe social and communication difficulties,” but this oversimplification fails to capture the full diversity of autistic experiences, particularly among high-masking autistic adults with average or above-average intelligence. These individuals have learned to socially "mask" or camouflage their autistic traits at times, which can lead to significant delays in accurate diagnosis and a lack of understanding from healthcare professionals and support networks.

This article aims to dispel common misconceptions, reduce stigma, and foster deeper understanding and acceptance of high-masking autistic adults, particularly those who may have been diagnosed later in life. While autism is a neurodevelopmental difference present from birth, the manifestation of traits can vary widely, especially among individuals who have developed sophisticated masking strategies to navigate complex social and professional environments.

Despite an ability to mask autistic traits at times, without acceptance and accommodations, high-masking autistic people often experience significant challenges. It is crucial for healthcare professionals to recognize that autism can present in ways that challenge traditional stereotypes, and to approach each individual with an open mind and a willingness to understand their unique experiences.

Ask yourself: What might an adult “seem like” if they experience many autistic differences while also possessing average or above average intelligence?

Consider my story: I am autistic and a well-regarded psychologist, yet I didn't recognize that I’m autistic until I was 29—no one did. My experience is not uncommon and sheds light on the complexities of autism, particularly in adults with lower support needs. Further, there are countless autistic individuals excelling as therapists, medical doctors, lawyers, accountants, teachers, and in many other demanding professions; this prevalence challenges common perceptions about autism. If this sounds surprising or hard to believe, please read the remainder of the article.

1: Misconceptions and Misdiagnosis: Why Autism is Often Overlooked in Adults

High masking autistic presentations can pose significant challenges in diagnosis and recognition, particularly among individuals with average or above-average IQ. This is primarily due to their ability to conceal autistic traits through learned behaviours and social masking, developed over decades to blend in with peers and trying to meet societal expectations, as well as alternative approaches to theory of mind. Extensive masking tends to lead to identity confusion, stress, burnout, low self-esteem, harsh internal self-talk, and so on—not to mention the social consequences from peers for often acting differently. This frequently combines to cause autistic people mental health difficulties, which may or may not lead to interaction with the healthcare system.

Misdiagnosis is common, with autistic traits being mistaken for anxiety, shyness, or other psychological conditions. Historical shifts in diagnostic criteria, gender biases in diagnosis, societal and cultural norms, and a lack of awareness and education among many healthcare workers have further complicated identification.

Definitions:

Masking in autism is an unconscious or conscious effort to hide and cover one’s own self from the world, as an attempt to accommodate others and coexist. ~Jenara Nerenberg

High-masking presentations of autistic traits are often marked by:

• Internalization

• Very frequently modifying one's behaviour, expressions, and mannerisms (consciously or unconsciously) to conform to societal expectations. This often involves intense self-monitoring and suppression of natural responses, which can be mentally and emotionally taxing

• Having interests that may align more closely with those of peers of a similar age and gender

• A socialization process that emphasizes agreeableness and refined social skills to avoid punishment

These traits are further augmented when individuals with this presentation of autism have superior language skills and a higher IQ.

Neurodiversity reframes autism, ADHD, dyslexia, Tourette’s, synesthesia, and similar by celebrating differences in brain function and behaviour as natural expressions of human diversity rather than flaws. This viewpoint posits that neurodivergence is a normal aspect of human history and should be respected, understood, and supported rather than pathologized. Resources such as the Autistic Self Advocacy Network or books such as Divergent Mind by Jenara Nerenberg explore this concept further. By adjusting the environment, reducing stigma, and valuing individual dignity, neurodivergent individuals can flourish. Familiarity with the "social model" of understanding autism and related ideas, including their advantages, disadvantages, and potential controversies, helps provide well-informed and comprehensive care (see research here).

High-masking autistic adults often display an unconventional yet effective theory of mind

Much of this article hinges upon challenging the misconception that autistic people aren’t able to apply a complex theory of mind—hence the etymology of the term “autism.”

High-masking autistic individuals often utilize a intensely analytical process known as "deep compensation" to achieve effective Theory of Mind (the capacity to understand other people by ascribing mental states to them, including the knowledge that others' beliefs, desires, intentions, emotions, and thoughts may be different from one's own) or “cognitive empathy” which differs from “affective empathy.” This can (often) allow autistic people to navigate even complex social situations “successfully,” albeit with greater effort and time. “Success” here varies based on history of intensely observing social behaviours, researching and practicing socializing, and trial and error, often having “better” outcomes in familiar scenarios.

Years or decades of practice masking can lead to very “effective,” though time-limited, masking of autistic traits (which is not healthy or desirable, generally). This is especially common among autistic people with average or above-average IQ and lower support needs. It can be very challenging to identify some autistic adults unless a thorough assessment is completed by an assessor with specialized experience.

How could autism be missed during childhood?

Autism, as a neurodevelopmental disorder, is typically expected to be diagnosed during childhood. This common assumption contributes to the misconception that a diagnosis of autism in later stages of life is improbable. However, there are numerous reasons why autism might go unnoticed or undiagnosed in childhood, such as:

1. Misattribution and Co-occurring Conditions: An autism diagnosis may be overlooked when behaviours typical of autism are mistakenly attributed to anxiety, trauma, shyness, or other similar concerns. This misattribution is common due to the high rates of conditions that can co-occur with autism, complicating the recognition of underlying autistic traits. This issue is particularly pronounced if healthcare providers selectively focus only on certain aspects of a client’s experience, or if we “twist facts to suit theories, instead of theories to suit facts”—a classic example of confirmation bias.

2. Family Dynamics: When parents are neurodivergent or exhibit traits associated with the broad autism phenotype, autistic behaviours in their children may seem normal to them thus can go unnoticed. Considering the significant genetic links in autism, such scenarios are far more common than might be expected.

3. Abuse or Neglect: Traumatic experiences can mask or overshadow signs of autism, and when caregivers are disengaged from their parenting responsibilities, they are less likely to notice (or act on, if they do notice) autistic differences.

4. Stigma: A surprising number of parents who are told by a doctor, therapist, or teacher that their child is showing some autistic traits and that an assessment is advisable, but then the parents choose not to proceed any further. I empathize somewhat with these parents, as historically there has been a lot of stigma related to autism, but I believe this is an unwise choice and is detrimental to autistic people in almost all cases. It is extremely useful to know that you are autistic, if you are. Tragically, I hear variations of this story from many clients (probably 30 to 40%), often concluding with “growing up, my family didn’t believe in getting treatment for mental health concerns.”

5. Gender Bias in Diagnosis: Girls and women are often under-diagnosed with autism due to gender stereotypes and the misconception that autism predominantly affects males, leading to a bias in recognition and referral for diagnosis. This broadly applies to most marginalized groups, unfortunately.

6. Lack of services: Many regions, particularly more rural areas, have fewer mental health services or specialists available.

See this 2020 research for more details.

How could autism be missed during adulthood?

Social masking is very prevalent among autistic adults with average or above-average IQ, and this masking can make it hard to detect autistic traits. These clients often will have spent decades learning, with increasing subtlety, how to hide their autistic traits in response to all the implicit and explicit criticism and rejection they receive for social differences. Masking can lead to the under-recognition of autistic traits during social and clinical exchanges, particularly if the observer is not actively alert to this phenomenon.

Common Misconceptions and Factors that contribute to the challenges of identifying autism in adults:

1. Masking: described above. Adults who camouflage their autism traits in daily life likely engage in extensive masking and possess a functional to excellent theory of mind (attained via non-standard means). Without these abilities, their autistic traits would likely have been identified in childhood. This level of masking, which involves both shallow and deep compensation strategies, is exhausting and discouraged, as it can lead to burnout and other health issues. Again, masking can lead to the under-recognition of autistic traits during social and clinical exchanges, particularly if the observer is not actively alert to this phenomenon.

2. Gender Differences in Presentation: Autism tends to be diagnosed more often in males than females, which may have some genetic origins, and this certainly seems to be impacted by how people who are “assigned female at birth” tend to be socialized in the Western world. Autistic women quite often get mis-diagnosed or under-diagnosed with anxiety, borderline personality disorder, or bipolar disorder.

   Historically, many women’s health issues have been minimized, misdiagnosed, and dismissed in clinical and research contexts; see here, here, or here for background reading. Generally, the less social privilege you have, the more likely your experiences are to be marginalized in most of the world’s healthcare systems.

3. Evolution of Diagnostic Criteria: The diagnostic criteria for autism have undergone significant changes over time. Initially, the focus was mostly on autistic people with very high support needs, often overlooking presentations with average intelligence or lower support needs. Prior to DSM5 in 2013, you couldn’t have both an autism and ADHD diagnosis, even though these are now understood as having very high co-occurrence. Additionally, autism is (stereotypically) considered by some to be a “childhood condition,” and some healthcare providers may make the assumption that if you weren’t diagnosed as autistic in childhood then you almost certainly aren’t autistic.

4. Challenges in the Differential Diagnosis: Due to the significant overlap in traits between autism and other conditions, as well as the high incidence of co-occurring disorders, accurate diagnosis of high-masking autism can be challenging and requires extensive data collection and in-depth knowledge.

   Misdiagnoses or under-diagnoses frequently obscure the identification of autism in adults. Conditions such as anxiety, borderline personality disorder, PTSD, or ADHD are commonly diagnosed instead of autism, leading to a scenario where autism's primary characteristics are overlooked in favour of managing these other diagnoses which may or may not be accurate. These co-occurring diagnoses may exist alongside or even represent underlying autistic traits. Recognizing this complexity is important to understanding the full scope of the autistic experience in adults.

5. Societal and Cultural Factors: Societal and cultural norms can significantly influence the identification of autism. In some cultures, traits associated with autism may not be seen as problematic or may be attributed to other factors.

   Eye contact, for example, is used very differently in some parts of the world, as are other non-verbals. Many autistic people learn that eye contact is expected and force themselves to use it, and after decades of practice, sometimes only nuanced differences in eye contact modulation and integration with speech exist. Similarly, many autistic people use strategies to simulate or avoid the use of most eye contact in conversation (e.g., look at bridge of nose or eye brow instead, or take notes to indicate I’m paying attention but I have to look at my notes so I can’t look at you, inviting you to be next to me to see what I’m doing rather than across from me, etc.), with varying levels of success. Almost all high-masking autistic adults have at least a moderate understanding of the utility and expectations related to eye contact and can force themselves to use it temporarily, despite the discomfort (this is not encouraged).

   Regardless, there are a few countries were shaking your head for ‘yes’ and ‘no’ are (basically) reversed! As a clinician, it is all too easy to be unaware of some of these kinds of nuances and misinterpret something.

6. Lack of Awareness and Education: No one is an expert in everything, and expertise varies even within specialized fields. For example, as a psychologist my expertise does not extend to treating eating disorders or addictions, and I am not the right person to assess or treat those concerns. Further, I specialize in autistic adults; I do not assess or work with autistic children. Similarly, while doctors are highly specialized (in fields like psychiatry, surgery, or family medicine), public expectations often unrealistically assume that doctors have a broad knowledge base in all areas.

   This misconception extends to autism, particularly in adult presentations. Despite advancements, I frequently encounter healthcare professionals who are not adequately informed about the adult autistic experience, yet they are expected to offer diagnostic impressions, guidance, and support. The historical lack of autism awareness among educators and healthcare providers, coupled with limited parental understanding, has played a significant role in missed or delayed diagnoses. This knowledge gap was more pronounced for those who attended school in the 1980s, 90s, or early 2000s than it is today—and these the adults we’re talking about seeking a “late-diagnosis” now.

   This 2015 Study of Physician Knowledge and Experience with Autism in Adults highlights this issue. They interview 922 medical doctors and stated “Most providers reported lacking skills and tools to care for this adult patient population. A high proportion of adult providers were not aware that they had patients with ASD.”

   This 2019 systematic review covered Primary Care Physicians’ Knowledge of Autism and Evidence-Based Interventions for Autism. The authors concluded that primary care physicians “in a majority of studies had inadequate knowledge of autism and its associated treatments.” A search of the literature reveals a moderate amount of other related studies.

   My critique here is not intended to be directed at doctors. Similar challenges are evident across all healthcare sectors that I engage with and whose work I encounter (e.g., nurses, psychologists, clinical social workers, etc.). Of course, I also meet some healthcare workers who have incredibly deep knowledge and competence related to autism. The focus on physicians in my discussion stems from more accessible research or straightforward search terms, rather than a comprehensive reflection of physicians in particular. This possibly indicates a broader gap in research on this crucial topic across different healthcare disciplines.

7. Impact of Appearance/Social Presentation on Autism Recognition: Factors such as level of physical attractiveness can play a large role in perception of autistic masking and whether an autism diagnosis is believed or not. A colloquial term for this is “pretty privilege,” and extensive research over decades has shown that the more conventionally attractive a person is the more we pay attention to them, like them, want them to like us, want to help them out, empathize with them (especially with women), and so on. To some degree, the DSM5-TR addresses the effect of presentation and certainly functioning, stating that autistic “individuals with relatively better skills overall may experience different or even greater psychosocial challenges.”

8. Double Empathy Problem, Theory of Mind, and Alexithymia: Autistic individuals often perceive, think, and communicate differently from non-autistic individuals due to neurobiological variances, including differences in theory of mind and the frequent presence of alexithymia. These differences can become more pronounced in complex situations, and can lead to significant miscommunications. This is encapsulated in the “double empathy problem,” which posits that understanding often decreases as differences in perspective increase. This phenomenon is easily observed in cultural or socioeconomic disparities but is particularly relevant in autism, where differences in theory of mind are pronounced.

   Consider an autistic adult reflecting upon their unique experiences of emotions, sensory sensitivities, trauma, autonomic dysfunction, or burn out. Identifying whether one’s own subtle, internal experiences are atypical can be very challenging—especially given that approximately 50% of autistic people also have alexithymia. This challenge is compounded for those with difficulties in social communication (i.e., many autistic people), often making it hard to convey their nuanced experiences accurately to healthcare professionals.

   The risk of miscommunication is heightened when the listener is not autistic, leading to potential misdiagnoses. This risk is further heightened by masking, people-pleasing, difficulty regulating emotions, rejection sensitivity dysphoria, medical trauma, and so on. These issues can make interactions with healthcare professionals overwhelming (further reducing effective communication), particularly if the autistic individual's concerns are not taken seriously—a common and unfortunate reality.

   Miscommunication in such contexts can lead to misdiagnosis, with autistic individuals potentially receiving incorrect labels for their experiences. This misattribution risks inappropriate treatment, including unhelpful medication and support services, underscoring the need for healthcare professionals to develop a deeper understanding of autism's nuances. Training in recognizing autistic communication styles and adopting collaborative approaches to diagnosis and treatment can significantly improve care for autistic adults.

9. Misc: Some locations simply do not have adequate access to medical services, so the person might have otherwise been identified as autistic early on if they lived in a major city, but that’s not always the case. The internet allowed for vast sharing of information, and it’s never been easier to find great information about adult autistic experience, so people who wouldn’t have come across the information in past decades now are far more likely to do so and then wonder if they are autistic—though of course this brings along increased sharing of inaccurate information as well.

   
   The above is a long list, but hopefully it can help readers appreciate the complexity of the issue and dispel some oversimplifications or misconceptions.

Humility: An Invitation to Deepen Your Understanding of Autism

In discussions about autism, it’s vital to approach with humility and openness, especially if one's familiarity with the DSM5-TR autism criteria might not be current. It may help to reflect:

• How many of the DSM5-TR criteria of autism can I, right now and without looking, list off?

• How much accurate detail can I provide on each criteria?

• Do I know which criteria go in which category?

• Do I know which criteria are mandatory for an autism diagnosis vs which aren’t?

• Did my list contain anything that’s simply not found in the criteria?

• Do I know what changed in the autism criteria when the DSM5 came out in 2013? Or what changed in autism definitions when the DSM5’s text revision released in 2022?

I mean this without judgement: holding strong opinions on the likelihood of someone being autistic without having a thorough understanding of the DSM criteria and how they appear in adults can inadvertently lead to overlooking subtleties in high-masking autism. There are many areas in the vast and complex field of mental health that are outside my expertise, and I try to be curious and open-minded when I encounter those rather than feel I need to have an immediate and definitive stance on everything.

It’s okay to “not know” everything. A current gap in specific knowledge does not detract from one’s competence as a medical or mental health professional. However, responses rooted in defensiveness or arrogance can be counterproductive. “The biggest threat to human intellect isn’t being ignorant, but being under the illusion of knowledge.” I recognize and value the continuous efforts made by healthcare professionals towards their ongoing learning and professional development. My appeal here is for openness to expanding our collective understanding of adults who exhibit high levels of masking in autism. For those interested in a deeper look, I have included a list of resources at the end of this article.