What are the Different Forms of Autism?

In this article, we'll explore some of the different forms of autism and how they may present in individuals.

Published on
March 2, 2024

What are the Different Forms of Autism?

Understanding Autism Spectrum Disorder

Autism Spectrum Disorder (ASD) is a complex neurodevelopmental disorder that affects individuals in various ways. It is characterized by difficulties in social interaction, communication, and repetitive behaviors. Understanding the basics of ASD, including its definition and prevalence, is crucial for parents seeking information and support.

What is Autism Spectrum Disorder (ASD)?

Autism Spectrum Disorder is a lifelong condition that impacts the way individuals perceive and interact with the world around them. It is considered a spectrum disorder because the symptoms and severity can vary widely from person to person. Some individuals with ASD may require significant support in their daily lives, while others may have fewer challenges and be able to lead more independent lives.

ASD is characterized by three core areas of impairment:

  1. Social Interaction: Individuals with ASD often struggle with social communication and interaction. They may have difficulty understanding social cues, expressing emotions, and forming relationships.
  2. Communication: Difficulties in communication can manifest in different ways. Some individuals may have delayed speech or language skills, while others may have a rich vocabulary but struggle with pragmatic language (the use of language in social contexts).
  3. Restricted, Repetitive Patterns of Behavior: People with ASD may engage in repetitive behaviors, have restricted interests or routines, and show sensitivity to changes in their environment. These behaviors can provide comfort and predictability but may also interfere with daily functioning.

Prevalence and Diagnosis of ASD

The prevalence of Autism Spectrum Disorder has been increasing in recent years. According to the Centers for Disease Control and Prevention (CDC), approximately 1 in 36 children in the United States is diagnosed with ASD. Boys are more likely to be diagnosed with ASD than girls.

Diagnosing ASD involves a comprehensive assessment that considers various factors, including behavioral observations, developmental history, and input from parents and caregivers. The diagnostic process typically involves a team of professionals, such as psychologists, pediatricians, and speech-language pathologists, who evaluate the child's strengths and challenges across different areas of development.

Early identification and intervention are crucial for children with ASD. Timely diagnosis allows for access to early intervention services, therapies, and support that can help improve developmental outcomes and quality of life for individuals on the autism spectrum.

By understanding the definition and prevalence of Autism Spectrum Disorder, parents can better navigate the journey of supporting their child with ASD. Seeking professional guidance and accessing appropriate resources can make a significant difference in helping individuals with ASD thrive and reach their full potential.

The Spectrum of Autism

Autism Spectrum Disorder (ASD) is a complex neurodevelopmental condition that encompasses a range of symptoms and characteristics. Understanding the different levels of autism and the common features of Autism Spectrum Disorder can provide valuable insights into this condition.

Levels of Autism

In addition to the different forms of autism, there are also levels of severity that can affect how a person with autism interacts with the world. The Diagnostic and Statistical Manual of Mental Disorders (DSM-5) outlines three levels of autism:

Level 1: Requiring Support

Individuals at this level may have difficulty initiating social interactions and struggle with adapting to changes in routine or environment. They may require some support to navigate stressful situations.

Level 2: Requiring Substantial Support

Individuals at this level have more severe impairments in social interaction and communication. They may engage in repetitive behaviors or have difficulty expressing their needs or preferences. They require substantial support to navigate daily life.

Level 3: Requiring Very Substantial Support

Individuals at this level have significant impairments in all areas of functioning, including communication, social interaction, and behavior. They may require very substantial support to meet their basic needs and navigate the world around them.

It's important to remember that these levels are just a guide, and each person with autism is unique. With the right support and resources, individuals with autism can lead happy, fulfilling lives regardless of their level of severity. As a society, we can work towards creating a more inclusive world that celebrates neurodiversity and supports individuals with autism in achieving their full potential.

Common Characteristics of Autism Spectrum Disorder

While there are many different forms of autism spectrum disorder (ASD), there are several common characteristics that people with ASD share. One such characteristic is difficulty with social communication and interaction. People with ASD may struggle to understand social cues like body language or facial expressions, which can make it challenging for them to form relationships or interact socially.

Another common characteristic of ASD is rigid thinking patterns or repetitive behaviors. People with ASD may become fixated on certain topics or routines, which can be comforting but also limit their ability to adapt to new situations or experiences.

Sensory sensitivities are also common among people with ASD. They may be oversensitive to certain sounds, smells, or textures, which can cause discomfort or anxiety in certain situations.

It's important to remember that while these characteristics are common among people with ASD, not everyone with autism will experience them in the same way. Each person with ASD is unique, and it's important to approach them with patience, understanding, and an open mind. By working to create a more inclusive world that embraces neurodiversity, we can help individuals with ASD thrive and reach their full potential.

Different Forms of Autism

Autism Spectrum Disorder (ASD) encompasses various forms of autism, each with its own distinct characteristics and diagnostic criteria. In this section, we will explore four different forms of autism: Asperger's Syndrome, Pervasive Developmental Disorder-Not Otherwise Specified (PDD-NOS), Childhood Disintegrative Disorder (CDD), and Rett Syndrome.

Asperger's Syndrome

Asperger's Syndrome, also known as high-functioning autism, is a complex developmental disorder that affects how a person behaves, interacts with others and communicates. It is often characterized by above-average intelligence and a strong interest in specific topics.

People with Asperger's may struggle with social interactions and communication but they often have excellent memory skills and a unique perspective on the world.

Asperger's Syndrome is named after Hans Asperger an Austrian pediatrician who first described the condition in the 1940s. Asperger's is considered a "spectrum disorder," which means that it affects each person differently and to varying degrees.

Some people with Asperger's may have difficulty making eye contact or understanding social cues, while others may have difficulty with sensory processing or repetitive behaviors.

Despite the challenges that Asperger's can present, many people with the condition are able to lead fulfilling lives. With the right support, people with Asperger's can build strong relationships and pursue their interests and passions. There are many resources available for people with Asperger's and their families, including support groups, therapy, and educational programs.

Pervasive Developmental Disorder-Not Otherwise Specified (PDD-NOS)

PDD-NOS, or Pervasive Developmental Disorder-Not Otherwise Specified, is a form of autism that's used to describe individuals who have some symptoms of autism but not enough to meet the criteria for a diagnosis of classic autism or Asperger's.

People with PDD-NOS may exhibit subtle signs of autism, such as difficulty with social interactions, communication, or repetitive behaviors. However, unlike classic autism or Asperger's, PDD-NOS does not always present with the same set of symptoms, and may vary from person to person.

It's important to note that while individuals with PDD-NOS may have mild communication or social impairments, they can generally function well in daily life. With the right support and resources, many individuals with PDD-NOS can thrive and lead fulfilling lives.

Childhood Disintegrative Disorder (CDD)

Childhood Disintegrative Disorder is a rare form of autism that's characterized by significant developmental regression. It's a heartbreaking condition that affects a child's ability to communicate, socialize, and learn. Children with this disorder may develop normally until around age 2, then experience a sudden and severe loss of language, social skills, and other developmental milestones.

While the exact cause of Childhood Disintegrative Disorder is still unknown, researchers believe it may be related to genetic mutations or abnormalities in brain development. Unfortunately, there is no cure for this disorder, but early diagnosis and intervention can help improve outcomes for affected children.

Rett Syndrome

Rett Syndrome is a rare and complex neurological disorder that's almost exclusively found in girls. It's caused by a genetic mutation on the X chromosome and affects approximately 1 in 10,000 girls worldwide. The condition is often misdiagnosed as autism, cerebral palsy, or non-specific developmental delay.

Rett Syndrome is characterized by a loss of motor skills, communication, and social interaction. This means that girls with Rett Syndrome may have difficulty with walking, hand movements, and other basic motor functions.

They may also have difficulty speaking, making eye contact, and engaging with others socially. In addition to these symptoms, people with Rett Syndrome may also experience seizures and breathing problems, which can be life-threatening.

Early Signs and Symptoms

Recognizing the early signs and symptoms of Autism Spectrum Disorder (ASD) is crucial for early intervention and support. Autism presents itself through various challenges in social communication, repetitive behaviors, restricted interests, and sensory sensitivities. By understanding these early signs, parents and caregivers can seek appropriate guidance and intervention for their children.

Social Communication Challenges

One of the key early signs of ASD is social communication challenges. Children with autism may struggle with understanding and using verbal and nonverbal communication. They may have difficulties with:

  • Eye contact: Avoiding or having limited eye contact during interactions.
  • Gestures: Rarely using or responding to gestures like pointing or waving.
  • Facial expressions: Exhibiting limited facial expressions or difficulty interpreting the expressions of others.
  • Social reciprocity: Having difficulties engaging in back-and-forth conversation or sharing interests and emotions.
  • Understanding emotions: Struggling to comprehend or express emotions appropriately.

It's important to note that each child with ASD may demonstrate these challenges to varying degrees.

Repetitive Behaviors and Restricted Interests

Repetitive behaviors and restricted interests are another common early sign of autism. These behaviors often manifest in the following ways:

  • Repetitive movements: Engaging in repetitive body movements such as hand flapping, rocking, or spinning.
  • Rigid routines: Displaying a strong need for routine and becoming upset or anxious when routines are disrupted.
  • Intense focus: Having intense and narrow interests, often fixating on specific objects or topics.
  • Unusual play patterns: Exhibiting repetitive or ritualistic play behaviors, such as lining up toys or playing with them in a non-functional manner.
  • Stereotyped behaviors: Displaying repetitive or unusual vocalizations, such as repeating words or phrases.

These repetitive behaviors and restricted interests can provide a sense of comfort and predictability for individuals with autism.

Sensory Sensitivities

Many individuals with autism experience sensory sensitivities, which can impact their daily lives. Sensory sensitivities refer to heightened or reduced responses to sensory stimuli. Common sensory sensitivities include:

  • Hypersensitivity: Being overly sensitive to certain sensory stimuli, such as loud noises, bright lights, strong smells, or certain textures.
  • Hyposensitivity: Showing reduced sensitivity to sensory input, leading to a high threshold for pain, lack of response to extreme temperatures, or seeking intense sensory input.

These sensory sensitivities can significantly affect a child's comfort, engagement, and ability to focus in different environments.

Understanding these early signs and symptoms can assist parents and caregivers in recognizing potential indications of Autism Spectrum Disorder. If you notice these signs in your child, it is recommended to consult with a healthcare professional or developmental specialist for a comprehensive evaluation and appropriate support.

Early intervention and targeted therapies can make a significant difference in the lives of children with autism, enhancing their development and overall well-being.

Support and Intervention

When it comes to autism spectrum disorder (ASD), early support and intervention play a crucial role in helping individuals with ASD reach their full potential. This section will explore various support and intervention strategies that can make a positive impact on the lives of individuals with ASD and their families.

Early Intervention Services

Early intervention services are critical for children with autism. These services can help identify and diagnose autism early, which can lead to better outcomes in the long term. The goal of early intervention is to provide children with the support they need to reach their full potential and improve their quality of life.

Early intervention services may include speech therapy, occupational therapy, and behavioral therapy. These therapies can help children with autism develop communication skills, manage sensory sensitivities, and learn important social skills.

One effective early intervention program is called Applied Behavior Analysis (ABA). ABA has been shown to be effective in helping children with autism develop new skills and reduce problem behaviors. ABA therapy involves breaking down complex tasks into smaller steps and using positive reinforcement to encourage desired behaviors.

It's important for parents and caregivers to seek out early intervention services as soon as possible if they suspect that a child may have autism. The earlier a child receives intervention, the better their outcomes are likely to be.

There are many resources available for families seeking early intervention services for their child with autism. Local school districts or healthcare providers may offer these services or be able to refer families to trusted providers in the community. Additionally, there are many advocacy organizations that provide information and support for families navigating the early intervention process.

Therapies and Interventions

There are many different therapies and interventions available to support individuals with autism spectrum disorder (ASD) in reaching their full potential. Here are a few examples:

Speech Therapy

Speech therapy can be an effective tool for individuals with ASD who struggle with communication. A speech therapist can help teach language skills, improve social communication, and address issues like pronunciation or stuttering.

Occupational Therapy

Occupational therapy can help individuals with ASD develop the fine motor skills they need to perform daily tasks like dressing, grooming, and writing. An occupational therapist can also help address sensory sensitivities that may affect an individual's ability to participate in daily activities.

Behavioral Therapy

Behavioral therapy is a broad term that encompasses many different approaches to treating autism. One example is Applied Behavior Analysis (ABA), which was mentioned earlier as an effective early intervention program. Other behavioral therapies may focus on teaching social skills or reducing problem behaviors.

Social Skills Training

Social skills training can be helpful for individuals with ASD who struggle with social interactions. This type of therapy may involve role-playing exercises or group sessions designed to teach important social cues and communication skills.

Sensory Integration Therapy

Sensory integration therapy is a type of occupational therapy that focuses specifically on addressing sensory sensitivities. This type of therapy may involve exposure to different textures, smells, or sounds in a safe and controlled environment.

It's important to remember that not every therapy or intervention will work for every individual with ASD. It's important for families and caregivers to work closely with healthcare professionals to identify the best approach for their loved one's unique needs and strengths.

Creating a Supportive Environment at Home and School

Creating a supportive environment is crucial for individuals with ASD both at home and in educational settings. Here are some strategies to consider:

At Home:

  • Establishing a consistent routine to provide structure and predictability.
  • Creating a calm and organized environment to minimize sensory overload.
  • Using visual supports, such as visual schedules and social stories, to enhance understanding and communication.
  • Encouraging and reinforcing positive behaviors.
  • Seeking support from support groups and professional organizations.

At School:

  • Collaborating with teachers and school staff to develop an individualized education plan (IEP) or a 504 plan.
  • Implementing accommodations and modifications to support learning and participation.
  • Providing visual supports and clear instructions to aid comprehension.
  • Promoting social inclusion and fostering understanding among peers.
  • Training school staff on autism awareness and effective strategies for supporting students with ASD.

By utilizing early intervention services, implementing appropriate therapies and interventions, and creating a supportive environment, individuals with ASD can thrive and reach their full potential. It's important to work closely with professionals, educators, and support networks to tailor interventions to the unique needs of each individual with ASD.


What is the difference between classic autism and Asperger's Syndrome?

Classic autism is typically characterized by significant impairments in communication, social interaction, and behavior. Children with classic autism may have delayed language development or difficulty understanding social cues. They may also engage in repetitive behaviors like hand flapping or rocking.

Asperger's Syndrome, on the other hand, is often characterized by mild to moderate impairments in social interaction and communication. Individuals with Asperger's may have difficulty with nonverbal communication or understanding social norms. They may also have a narrow range of interests and engage in repetitive behaviors.

Is PDD-NOS considered a type of autism?

Yes, PDD-NOS is considered a form of autism spectrum disorder (ASD). It's used to describe individuals who have some symptoms of autism but not enough to meet the criteria for a diagnosis of classic autism or Asperger's.

How common is Rett Syndrome?

Rett Syndrome is a rare neurological disorder that affects approximately 1 in 10,000 girls worldwide. It almost exclusively affects girls because it's caused by a genetic mutation on the X chromosome.

Can Childhood Disintegrative Disorder be cured?

Unfortunately, there is no cure for Childhood Disintegrative Disorder. However, early diagnosis and intervention can help improve outcomes for affected children.

Are there different levels of severity within ASD?

Yes, the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) outlines three levels of severity within ASD. These levels are based on the amount of support an individual requires to navigate daily life.

What types of therapies are available for individuals with ASD?

There are many different therapies available for individuals with ASD, including speech therapy, occupational therapy, behavioral therapy, social skills training, and sensory integration therapy. It's important to work closely with healthcare professionals to identify the best approach for each individual's unique needs and strengths.

What resources are available for families of individuals with ASD?

There are many advocacy organizations, support groups, and educational programs available for families of individuals with ASD. These resources can provide valuable information and support as families navigate the challenges of living with autism spectrum disorder.


Autism is a complex disorder that can present in many different ways. Understanding the different forms of autism can help us better understand and support individuals on the spectrum.

Whether it's classic autism, Asperger's Syndrome, PDD-NOS, Rett Syndrome, or Childhood Disintegrative Disorder, each form of autism is unique and deserves to be recognized and respected. By promoting understanding and acceptance, we can create a more inclusive society for all individuals, regardless of their neurodiversity.