What Are the 5 Types of Autism?

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What is Autism?

According to the National Autistic Society, “Autism is a lifelong developmental disability which affects how people communicate and interact with the world.” Around 700,000 people in the U.K, and 1% of people worldwide have autism.

People with autism may experience the following difficulties:

  • Challenges with social communication and interaction
  • Repetitive and restrictive behaviour
  • Over-sensitivity, or under-sensitivity, to light, sound, taste, or touch
  • Highly focused interests or hobbies
  • Extreme anxiety
  • Meltdowns and shutdowns

People with autism may also possess the following strengths:

  • The ability to read at an early age (also known as hyperlexia)
  • Memorising and learning
  • Visual thinking
  • Logical thinking
  • If the person is able, they may excel in academic areas such as science, engineering, and mathematics because they are technical and logical subjects that do not rely too much on social interaction.
  • Having an extraordinary memory
  • Being precise
  • Having exceptional attention to detail
  • Being honest and reliable
  • Having an excellent sense of direction
  • Being very punctual
  • Strong adherence to rules
  • The capability of concentrating for long periods of time when motivated
  • A drive for perfection and order
  • Excellent problem-solving skills
  • A rare freshness and sense of wonder

Autism is a spectrum condition, hence the name Autistic Spectrum Disorder (ASD).

Up until 2013, the following types of autism were diagnosed separately:

  • Asperger syndrome
  • Pervasive Developmental Disorder – Not Otherwise Specified (PDD – NOS)
  • Rett syndrome
  • Childhood Disintegrative Disorder (CDD), also known as Heller’s syndrome
  • Classic Autism, also known as Kanner’s Syndrome

From 2013 onwards, anyone who was diagnosed with any of these types of autism is given the official diagnosis of ASD.

Asperger Syndrome

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The term Asperger Syndrome (AS) derives from a 1944 study by the Austrian paediatrician Hans Asperger. The British psychiatrist Lorna Wing introduced the term in the 1980s. Up until 2013, AS was diagnosed as a separate condition from Autistic Spectrum Disorder (ASD). Nowadays it is a part of the entire spectrum and people no longer receive an AS diagnosis in the UK.

People with AS experience difficulties with:

  • Maintaining eye contact
  • Knowing how to communicate in social situations
  • Understanding social cues, body language and facial expressions
  • Showing their own emotions
  • Speaking in varied intonations
  • Talking about people other than themselves
  • Seeing the world from another person’s perspective
  • Discussing a wider range of subjects
  • Coping with change

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

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PDD-NOS was a type of autism that was diagnosed before 2013. It was used to describe an individual who had impairment in social skills; the inability to successfully interact with other people; problems with verbal or non-verbal communication; or stereotyped behaviour, interests, and activities.

Symptoms of PDD-NOS include the following:

  • Problems understanding and using language
  • Difficulty relating to people
  • Unusual play with toys
  • Problems with changes in routine
  • Repetitive movements or behaviour
  • Difficulties with initiating or maintaining a conversation
  • Making poor eye contact, or not making eye contact at all
  • Difficulty with expressing their own feelings or emotions
  • Not understanding the feelings of others
  • Trouble with understanding non-verbal cues, such as facial expressions, gestures, or postures
  • Having a slow response to someone calling their name
  • Experiencing a greater or lesser sensitivity to sensory stimulation, such as sounds and lights
  • Having an intense, very focused interest in specific objects or topics
  • Developing specific food preferences, or refusing to eat certain foods

Rett Syndrome

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According to the NHS, “Rett Syndrome is a rare genetic disorder that affects brain development, resulting in severe mental and physical disability.” It is more common in girls, and it is estimated to affect about 1 in 12,000 girls born each year. Rett Syndrome is only rarely seen in boys. One notable person who had Rett Syndrome was Coleen Rooney’s late adopted sister, Rosie.

Rett Syndrome was previously diagnosed as a subtype of PDD.

The symptoms of Rett Syndrome appear in four different stages:

  • Stage One Symptoms
    • Low muscle tone
    • Difficulty feeding
    • Unusual, repetitive hand movements or jerky limb movements
    • Delay with development of speech
    • Mobility problems that affect sitting, crawling, and walking
    • Lack of interest in toys
  • Stage Two Symptoms
    • Loss of the ability to use hands purposefully
    • Periods of irritability and distress
    • Social withdrawal
    • Unsteadiness and awkwardness when walking
    • Problems sleeping
    • Slowing of hand growth
    • Difficulty with eating, chewing, and swallowing
  • Stage Three Symptoms
    • Seizures that become increasingly common
    • Irregular breathing patterns
  • Stage Four Symptoms
    • Development of a spinal curve, known as scoliosis
    • Muscle weakness
    • Losing the ability to walk

Childhood Disintegrative Disorder (CDD, also known as Heller’s Syndrome)

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Childhood Disgenerative Disorder was previously given as another subtype of PDD.

Children who were diagnosed with CDD developed normally to the approximate age of 3 or 4 and then, over a short period of time, lost previously acquired motor, social and language skills.

CDD symptoms included the following:

  • Similar social, communicative, and behavioural features to those that children with autism experience
  • Restrictive, repetitive, or stereotyped patterns of activities, behaviour, and interests
  • Loss of toilet training skills
  • Regression of gross motor skills, such as pedalling a tricycle
  • Regression of fine motor skills, such as drawing shapes
  • Having trouble with transitioning from being awake to falling asleep

Classic Autism (AKA Kanner’s Syndrome)

April Slocombe and her brother, Adam, are sitting on a couch. They are both wearing autistic sibling-themed T-shirts.
Adam, the brother of our content volunteer, April, was diagnosed with Kanner’s Syndrome, while April has ASD. They were both diagnosed with their types of autism in 1991.
Image by Gail Slocombe (April and Adam’s mother).

The alternative name for ‘classic autism’, Kanner’s Syndrome was named after Leo Kanner, another Austrian paediatrician. In 1943, Kanner made observations of a then-5-year-old boy named Donald T, who was happiest when he was alone; was oblivious to everyone around him; spun toys and himself around; shook his head from side to side; and had temper tantrums when his routine was disrupted. Kanner also observed 10 other children and wrote a paper named Autistic Disturbances of Affective Contact.

Before 2013, Kanner’s Syndrome was defined as the most serious form of autism.

People with Kanner’s Syndrome had noticeable problems with speech, behaviour, and social interaction. They were often hypersensitive and avoided interaction with other people on many occasions.

Symptoms of Kanner’s Syndrome included the following:

  • Rigid, dogmatic behaviour
  • Repetitive actions and speech
  • Self-harm, e.g., hitting themselves
  • Withdrawal and avoiding social situations
  • Obsessive behaviour, such as focusing on a single interest
  • Sensitivity to lights, smells, sound, taste, texture, and touch
  • A dislike of being cuddled
  • Difficulties with verbal language
  • Inability to interpret body language
  • Avoiding eye contact
  • Having an average or below-average intelligence
  • Wooden or monotonal speech pattern if the person can speak
  • Preferring to interact with inanimate objects to people
  • Having a rigid routine
  • Inability to move out of their comfort zone

Many people who were diagnosed with Kanner’s Syndrome are non-verbal. Alternative ways for them to communicate include using gestures and PECS cards. PECS cards are cards that have a picture and a word on each one. A non-verbal person uses one of these cards to tell someone else what they want. For example, if a non-verbal person wants to watch TV, they show the other person a card with a picture of a television and the word “television” underneath the picture.

Diagnosing Autism

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If you’re a parent who thinks that your child has autism, speak to your GP. They can refer you to a medical professional such as a psychologist, a paediatric neurologist, a developmental paediatrician, or a psychologist. They may diagnose your child with autism.

Adults who suspect that they have autism can also discuss their symptoms with their GP. The GP will then refer the adult to a psychologist or a psychiatrist who can assess their behaviours and symptoms and help determine if they have autism.

Why not check out our autism test and Asperger’s syndrome Test or start a spiky profile?
(Please note these are not diagnostic tools)

Blog Author

April Slocombe


Neurodivergent