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What is the Triad of Impairments in autism?

Written by Sarah Norman

Review by Alina Ivan

Tagged in

  • Science


Feb 2, 2023, 6 min read

If you’ve been researching autism or neurodivergence then you may have come across the ‘Triad of Impairments’ model used to characterise the things people with autism sometimes find difficult. This phrase may sound like a complicated concept but it’s actually very simple, and we’ll break it all down in this article.

At Augmentive, we aim to provide holistic, tailored mental health support to everyone so they can live their life to the fullest. So if you have been trying to learn more about autism (whether for yourself or a loved one), we’re here to help.

Let’s dive deep on the Triad of Impairments; the areas of difficulty, the more recent ‘Dyad of Impairments’ model, and what to do if you recognise some of the characteristics mentioned.

First things first...

What is autism?

Autism is a neurodevelopmental condition affecting how people interact with others, the world around them, and how they understand and respond to sensory information. It can affect people with different levels of severity which makes it difficult to diagnose.

That said, autism is becoming more common and understood in recent years. Around 1 in 100 people in the UK are believed to have some form of autism, and with more understanding of autism than ever before, more people are recognising the symptoms in themselves or loved ones and seeking a diagnosis. If you want to, you can read more about autism here.

What is the Triad of Impairments and who coined the term?

If you’re already picturing a triangle, you’re not far off. The Triad of Impairments is a model for recognising autistic traits, and it can be visualised in 3 sections (more on these below). The model was introduced around 1979, when Dr Judith Gould and Lorna Wing OBE researched the prevalence of autism in children in an area of London.

In one group they noticed a pattern of difficulties with social interaction, communication and imagination. In response, they created the ‘Triad of Impairments’, and although it was noted these children did not fit the typical autism traits (as described by Leo Kanner), they were indeed thought to be on a spectrum of autism and could be categorised as such using the Triad of Impairments.

At the time, this new model enabled families to further understand and relate to loved ones with autism. Though it has since evolved, it remains a key part of autism diagnosis.

What are the 3 areas of difficulty?

Autism is identified when observing three key aspects of a person; their communication skills, their social interaction, and their imagination. It’s important to remember every person with autism is unique, therefore they will have different experiences and characteristics and can also change with age or depending on the situation. However, elements of these 3 areas are often evident in people on the autism spectrum.

The autism spectrum's triad of impairments

Let’s break them down further:

Social communication

Those with autism may struggle with social communication which could mean some of the following traits are present:

  • They struggle to read facial expressions, body language, gestures, or tone of voice
  • They don’t enjoy communicating with others around them
  • They find it hard to express their own emotions
  • They tend to talk ‘at’ people rather than ‘to’ them
  • They don’t always understand the emotions or beliefs of others

When it comes to communication, some people with autism can speak while others are non-verbal, so there is certainly a spectrum of communication.

Quick Tip: When someone with autism can’t communicate effectively, they can become frustrated or their mood can take a dip. If you want to improve your communication with them, you can do this by making instructions very simple, checking you have understood the person correctly, and using visual aids where appropriate.

"Social communication means talking with people as well as 70% of the non-verbal communication as well."
- Dr Khurram Sadiq, Consultant Psychiatrist

Social imagination

People with autism can struggle with social imagination, which means:

  • They may have trouble imagining the world from someone else's perspective
  • They may not understand others around them have different thoughts/feelings to theirs
  • They may not understand ‘Theory of Mind’, or have the capacity to identify the mental state of others around them
  • They can have rigid thought patterns and become frustrated by changes to their routine because they can’t imagine things a different way
  • They may take things you say literally instead of imagining what else you could mean

Some people with autism can have this difficulty with social imagination, sometimes referred to as mindblindness. They may say inappropriate things, not alter their behaviour to help you, and have inappropriate responses to emotions.

"In social interactions they may misinterpret a lot of things and that can put them off friendships or make them distant with relatives. They will say things that are factual which makes it seem like they say things without thinking and this may cause offence. When it comes to social imagination, in spontaneous conversation they go blank and find it difficult to be innovative in starting new conversation or improvising in conversation."
- Dr Khurram Sadiq, Consultant Psychiatrist

Social interaction

Finally, those with autism may find social interaction difficult, which can lead to:

  • An inability to understand what others mean by their words or body language
  • A lack of understanding around different societal expectations
  • A struggle to start and maintain friendships and relationships
  • A lack of understanding around reading social cues
  • Inappropriate touching and issues with personal space

Quick Tip: If social interaction is a problem for a loved one you can help them understand by being direct about your feelings and emotions, reassuring them when plans change, and being descriptive when explaining what those changes will look like.

"In terms of social interaction, social gatherings can be very difficult. Sometimes one may want to go but once they are in the situation they don’t like it. Smaller groups and people they know won’t be a problem. After social interaction someone with autism may feel drained as it requires extra energy to come out to do something that does not come naturally to them. They may experience burn out the next day with no energy to get out of bed and talk."
- Dr Khurram Sadiq, Consultant Psychiatrist

What is the ‘Dyad of Impairments’?

And then there were two! The Triad of Impairments has been used for many years and is still considered today, however the Dyad of Impairments was introduced alongside the DSM-5 in 2013, otherwise known as the Diagnostic and Statistical Manual of Mental Disorders, to take into account sensory difficulties when assessing and diagnosing autism.

This new diagnosis involves discovering whether a person fits the milder or more severe description of autism, and the Dyad of Impairments method can help with this. In it, the subcategories of autism are merged into two sections instead of three, which highlights the sensory issues and social communication difficulties people with autism sometimes face.

The autism spectrum dyad of impairments

The Dyad of Impairments splits the characteristics of autism into 2 areas:

  • Impairment in social communication and interaction (similar to the Triad of Impairments)
  • Restrictive, repetitive patterns of behaviour

What are some restrictive, repetitive patterns of behaviour?

Restrictive and repetitive patterns of behaviour could include:

  • Repetitive and ritualistic patterns and actions that, if interrupted, can cause stress
  • Reactions to sensory overstimulation input like pain, temperature, sounds or textures
  • Rigid thinking patterns (for example, a need to take the same route every day)
  • Obsessive behaviours (for example, lining up toys in a certain order)
  • Fixated interests with high intensity
  • Repetitive motor movements or phrases
  • Routines and rules rarely deviated from

What does the addition of the Dyad of Impairments mean for autism diagnosis?

It’s important to note this change will not revoke any existing autism diagnosis. However, it should help people who have not yet been diagnosed to get a faster diagnosis of autism and a clearer understanding of how their mind works.

What should I do if I think I have autism?

First of all, it’s important to note that while the DSM-5 is a great tool, it is not the only resource practitioners use to make an autism diagnosis. Diagnosing Autism requires a specially trained professional. If you want to learn more about how to be assessed for autism as an adult, you can read our article: Autism in adults: What to expect from an autism assessment.

Or if you think your child may be showing signs of autism, this article could help: Diagnosing Autism: Understanding the Complexities of Identifying Autistic Traits in Children.

Whether you’re feeling off-kilter or want to shake up your routine, our state-of-the-art mental wellbeing platform gives you quick and seamless access to world-class support on your terms, from a private autism assessment or review, to broader mental health care: join us today.

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