Autistic Definition & Prevalence
“Autistic definition” is googled by over 22,000 people each month. The good thing is that more and more people are seeking information about autism. Some are new to autism. They might be a new parent or family member, a new special education teacher, SLP, OT, or other professionals. No matter who they are, they are looking for information.

What Is Autism?
According to the National Institute Of Health, autism Autism is defined as a neurological and developmental disorder that affects how people interact with others, communicate, learn, and behave. Autism can be diagnosed at any age. It is described as a “developmental disorder” because symptoms generally appear in the first 2 years of life.
Autism was first described by Swiss psychiatrist Eugen Bleuler in 1911, who used the term “autism” to refer to a symptom of schizophrenia. However, it wasn’t until the 1940s that autism was recognized as its own disorder. In 1943, Leo Kanner, an Austrian-American psychiatrist, published a paper describing a group of children who showed a distinct set of social and communication difficulties. Kanner called this disorder “early infantile autism,”. It was characterized by a lack of interest in social interaction, delayed speech development, and repetitive behaviors.
In the 1960s and 1970s, researchers began to identify a wider range of autistic traits and behaviors. The autistic definition started to change and expand. They recognized that not all autistic children had delayed speech development. They also noticed that some had exceptional abilities in areas such as math, music, or other areas. This led to the development of the concept of the autism spectrum. The spectrum recognizes that autism is a spectrum disorder, with a wide range of characteristics and symptoms. Most states now have the educational label of autism spectrum disorders. It is a category for children to receive special education services.
Autism DSM Five
Over the past 20 years, there have been significant changes to the diagnostic criteria for autism within the Diagnostic and Statistical Manual of Mental Disorders (DSM), particularly between the DSM-IV and the DSM-5. The DSM is what is used for a medical diagnosis, not an educational label. Here’s a little summary of the changes over time
The DSM-III was published in 1980, and it established autism as its own separate diagnosis of “infantile autism” and described it as a “pervasive developmental disorder”. In this edition , the autism diagnosis was now distinctly different from schizophrenia.
In the DSM-IV, autism was classified under the umbrella term “Pervasive Developmental Disorders” (PDD), which included five separate diagnoses:
- Autistic Disorder
- Asperger’s Syndrome
- Rett’s Disorder
- Childhood Disintegrative Disorder
- Pervasive Developmental Disorder Not Otherwise Specified (PDD-NOS)
To be diagnosed with Autistic Disorder, individuals had to meet criteria across three domains: social interaction, communication, and restricted, repetitive patterns of behavior, interests, or activities.
Asperger’s Syndrome, on the other hand, was characterized by social interaction difficulties and restricted repetitive behaviors, but without significant delays in language or cognitive development.
The DSM-5, published in 2013, made several major changes to the diagnostic criteria for autism:
- Autism Spectrum Disorder (ASD) replaced the PDD category, unifying Autistic Disorder, Asperger’s Syndrome, and PDD-NOS under one diagnosis. Rett’s Disorder and Childhood Disintegrative Disorder were removed from the autism classification.
- The three domains of impairment were restructured into two categories: “persistent deficits in social communication and social interaction” and “restricted, repetitive patterns of behavior
To be diagnosed with autism, a person must exhibit these symptoms early in life, typically before the age of three.
The DSM-5 also recognizes that autism is a spectrum disorder and that individuals with autism may have varying levels of impairment in social communication, behavior, and interests. As you can see, the autistic definition is evolving and changing over time.

Prevalence Of Autism
Now let’s talk about the prevalence of autism over the years. Over the past 25 years, there has been a significant increase in the reported prevalence of autism. This rise can be attributed to a variety of factors, including increased awareness, better diagnostic tools, and changes in diagnostic criteria.
In the early 1990s, the prevalence of autism was estimated to be around 1 in 2,500 to 1 in 1,500 individuals. At that time, the diagnostic criteria for autism were more restrictive, and the concept of the autism spectrum wasn’t really a thing yet. As a result, many individuals with milder forms of autism or Asperger’s syndrome were likely not diagnosed.
During the 2000s, the prevalence of autism began to rise steadily. In 2000, the Centers for Disease Control and Prevention (CDC) reported a prevalence of 1 in 150 children in the United States. This was during my first year of teaching! So, in my teaching career so far, I’ve seen the prevalence go from 1 in 1500 to 1/150 to 1/36. This increase was likely due to a combination of factors, such as improved awareness and screening, changes in diagnostic criteria, and better access to services. In 2006, the CDC introduced the Autism and Developmental Disabilities Monitoring (ADDM) Network, which provided more accurate and consistent data on autism prevalence in the United States.
In 2012, the prevalence of autism in the United States was 1 in 88 children. By 2014, this number increased to 1 in 59 children, and in 2018 and 2020, the CDC reported that 1 in 54 children were diagnosed with autism spectrum disorder (ASD). New statistics were recently released by the CDC and the prevalence of autism is now 1 in 36 in the United States.
The Neurodiversity Movement
When talking about autism and autism acceptance, it’s important to talk about the neurodiversity movement. This movement is a social and advocacy movement that promotes the understanding and acceptance of neurological differences as a natural and valuable part of human diversity. It is a social, political, and human rights movement led by Autistic, Neurodivergent, and other disabled people with the end goal of acceptance. It is a Cultural Movement. The term “neurodiversity” was first coined by Australian sociologist Judy Singer in the late 1990s. The movement has since gained momentum and is now a significant force in challenging traditional views of neurological conditions, such as autism, ADHD, dyslexia, and other developmental and learning differences.
The neurodiversity movement is based on several key principles.
One is that neurological differences are a natural part of human diversity: The movement asserts that neurological variations like autism, ADHD, and dyslexia are not inherently pathological or disorders to be cured. Instead, they are a natural part of human genetic diversity, much like differences in race, gender, or physical ability. As you can see, the neurodiversity movement is changing the autistic definition and how we look at it.
Another aspect of the movement is the emphasis on strengths and abilities: Advocates of neurodiversity argue that neurodivergent individuals possess unique strengths, skills, and perspectives that can be so valuable in various aspects of life. Rather than focusing on deficits and disabilities, the neurodiversity movement seeks to celebrate and harness these strengths and abilities.
Challenging the medical model of disability is another focus of the neurodiversity movement. The medical model of disability often treats neurological differences as defects that need to be corrected or cured. On the other hand, the social model of disability argues that societal barriers and lack of accommodations are the primary factors contributing to the challenges faced by neurodivergent individuals.
The also movement encourages neurodivergent individuals to advocate for themselves and their needs, empowering them to have a voice in shaping policies, services, and societal attitudes toward neurodiversity. It also promotes the inclusion of neurodivergent individuals in decision-making processes that affect their lives.
The neurodiversity movement seeks to redefine what is considered “normal” by acknowledging that there is no single, correct way of thinking, learning, or processing information. By recognizing the value of diverse neurocognitive experiences, the movement aims to challenge and expand society’s understanding of what is considered typical or normal.

Identity First Vs. Person First Language
As the autistic definition changes, another aspect to touch on is the idea of identity first language vs person first language. I know for me, for over 20 years, saying “autistic” would have been looked at as unprofessional because we were told to always use person first language. That would be “child with autism”. Hannah, an autistic woman shared with me that person-first language doesn’t work with people who are naturally biologically different, especially if they consider themselves part of a community like the Deaf community. “Person with deafness” not only doesn’t make sense, the effect is to minimize or erase the importance of deafness and the Deaf community to that person. Ironically, it can also have a condescending and dehumanizing effect, constantly re-emphasizing that abled people have to be reminded that people who can’t hear are still people.
Hannah said that the same thing applies to autistic people and the growing autistic culture. She said “We’ve suffered awful mistreatment in the past, and many of us continue to suffer because people believe we can be “cured.” Most of us don’t believe that anymore, or that we should be “cured” even if we could because we don’t believe that things like autism, ADHD, and dyslexia are diseases. Instead, based on a body of research that’s been growing since the late 1990s, we understand these things to be built-in neurological differences that aren’t inherently bad. They come with pros and cons, but many of the cons result from how society treats different or disabled people. For instance, many things that are stereotypically considered “symptoms” of autism are either indistinguishable from trauma responses or are directly caused by those trauma responses”.
She shares that person-first language emphasizes the personhood of the, well, person. This works for people who have contracted diseases, sustained injuries, and so on, and has generally been accepted in the medical community and culture in general. You would always say a person “has cancer,” not call them “cancerous” or a “cancerous person.”
For Hannah, when you say “autistic person,” it signals that you’ve listened to us and care about us, and are willing to treat us as fully-formed humans. And that’s why I, an autistic person, would like to be called an autistic person and not a “person with autism.”
In recent years, the neurodiversity movement has gained traction and has influenced various areas, such as education, workplace policies, and even legislation. Many schools and organizations are now adopting neurodiversity-friendly practices or neurodiversity-affirming practices, which emphasize individualized learning and support, strengths-based approaches, and accommodations for different learning styles and needs.
Despite its growing influence, the neurodiversity movement has also faced criticism, with some arguing that it downplays the challenges and struggles experienced by neurodivergent individuals and their families. However, the movement’s core message of acceptance, inclusion, and empowerment remains essential in promoting a more compassionate and understanding society for all.

Autism Acceptance Month
For the first 19 years of my career, we celebrated Autism Awareness Month. But over the last 4 years, the way we look at this has shifted. This is because we are now listening to autistic voices. Really listening to what autistic adults are saying about this.
Autism awareness refers to understanding and recognizing the existence of autism. The focus was on sharing what autism is, the characteristics of autistic individuals, and its prevalence in society. It often involved educating the public about the “symptoms
of autism, the challenges faced by autistic individuals, and the need for early detection and intervention. There also used to be a focus on finding a cure or making autistic kids look more neurotypical. The puzzle piece used to be the symbol used during Autism Awareness Month. Looking back now, the problem with this is that is told everyone (including autistic individuals) that something was missing in them or they were not a complete person. That they were a puzzle that needed to be solved. It sends the message that they need to be cured. This can lead to what is called masking. Masking is when autistic individuals learn, practice, and perform certain behaviors and suppress others in order to be more like the people around them. Masking can be incredibly damaging to the mental health of autistic youth and adults.
On the other hand, autism acceptance refers to recognizing and respecting the diversity of different neurotypes, including autism. The focus is more on accepting everyone for who they are and including them in society. This involves acknowledging that autism is a natural part of human diversity. It honors that autistic individuals have a unique perspective and way of experiencing the world. Autism acceptance focuses on creating an inclusive society that values and celebrates neurodiversity. It makes sure to provide support and accommodations to autistic folks to help them reach their full potential. The focus is not on providing therapy to make them more “neurotypical”.
With Autism Acceptance, the symbol that is being used is an infinity symbol. This symbol represents neurodiversity. It “describes the idea that people experience and interact with the world around them in many different ways; there is no one “right” way of thinking, learning, and behaving, and differences are not viewed as deficits.” You guys, just think about that definition and how much more accepting and supportive it is! Words and symbols mean a lot and they can change over time. When we know better, we do better.
While autism awareness is an important first step in understanding and recognizing autism, autism acceptance goes beyond awareness. It focuses on promoting inclusion and support for autistic individuals to thrive. By embracing and celebrating neurodiversity, we can create a more inclusive and supportive society for everyone.
Four Ways To Move To Acceptance
Acceptance: Accepting individuals with autism for who they are is the first step toward supporting them. We need to acknowledge and respect their unique strengths, challenges, and perspectives. We should listen to what autistic adults are telling us about their past experiences in school and in society.
Communication: Communication is key when it comes to supporting autistic children. It’s important to communicate in a way that they can understand. It’s equally important to be patient and give them time to respond. Be aware of nonverbal communication and avoid making assumptions about what they are feeling or thinking. We need to presume competence!
Sensory needs: Many autistic folks have sensory sensitivities and differences, so it’s important to be aware of their sensory needs and preferences. This might include providing a quiet space or an area with reduced visual or auditory input.
Accommodations: Providing accommodations can help individuals with autism thrive. This might include things like providing a visual schedule, using assistive technology or allowing for breaks in their day. When I say “allowing breaks”, I mean just that. Allowing breaks when needed vs “earning breaks”.
Overall, supporting autistic individuals for who they mean embracing their uniqueness, and presuming competence. It means listening to autistic voices. It’s about respecting their needs and preferences in order to create a supportive environment where they can thrive.
Neurodiversity Affirming Provider
When it comes to most of us, as parents, educators, and therapists, what does this all mean? Well, Julie Roberts, a speech/language pathologist put into words what it means to be a neurodiversity-affirming therapist or educator. She says that the takeaway is that a neurodiversity-affirming therapist is trauma-informed, respectful, and culturally competent. She says to remember that autistic culture is a culture. An allied provider’s primary goal is to teach autism acceptance to professional peers, families, and the community. They help ensure their clients have body autonomy and express self-determination. Allied providers readily recommend and implement accommodations, supports, and modifications. They don’t fade these things when they’re working. If something is working to increase independence, don’t take it away. Neurodiversity-affirming services focus on making autistic people’s lives better. They do not focus on reducing autistic symptoms to make the people around them feel more comfortable.
For more information about the topics covered in this blog, plus autistic perspectives, go to:
- CDC Autism Prevalence Data
- Autistic Self Advocacy Network
- Neuroclastic
- Uniquely Human Book by Barry Prizant
- I Will Die On This Hill by Meghan Ashburn & Jules Edwards
In episode 12 of The Autism Little Learners Podcast, I talk in-depth about the information in this blog post. Choose where you want to listen from this list.
If you use visual supports in your classroom or home, you are going to want to sign up for this free Visual Supports Starter Set ASAP! Click here to have one sent to your inbox. Also, be sure to read more about visual supports and how they can help autistic children here.