Part B Of The Diagnostic Criteria Cause Part A

A man in overalls painting on the sky to reveal the word 'why'.
Image by Gerd Altmann from Pixabay

Key Takeaways

  • Part B of the DSM-5 diagnostic criteria can help explain the symptoms in Part A of autism.
  • Stereotyped movements, sensory issues, routines, and fixated interests can all interfere with social communication and relationships.
  • Understanding the underlying causes of autism symptoms allows for better strategies and interventions.
  • Autism is highly individual, and understanding the root causes rather than just diagnosing symptoms leads to more effective support.
  • A thorough understanding of autism's 'why' rather than just the 'what' is essential for finding suitable interventions.
  • Aspiedent offers autism profiling services that help individuals understand their unique challenges and improve outcomes. If you are interested in having an autism profile, please contact us.

In this blog post we consider the DSM-5 (2013) diagnostic criteria for ASD (Autism Spectrum Disorder). In this version of the DSM, all the diagnoses related to autism, such as Asperger Syndrome have been conflated into one diagnosis: Autism Spectrum Disorder.

The DSM-5 diagnostic criteria consist of two checklists: Part A which is about symptoms regarding communication and social communication and Part B which is about other symptoms found in autism. Normally, clinicians establish that the criteria for Part A are met before examining the criteria for Part B.

At Aspiedent, in order to find ways of helping autistic people, we identify what is causing the symptoms - the underlying issues. We have found that Part B of the diagnostic criteria for autism actually explain the Part A symptoms.

DSM-5 Diagnostic Criteria

Part A: social communication and social interaction – across multiple contexts

  • Deficits in social emotional reciprocity - for example, abnormal social approach and failure of normal back-and-forth conversation, reduced sharing of interests, emotions, or failure to initiate or respond to social interactions.
  • Deficits in non-verbal communication, - for example, poorly integrated verbal and nonverbal communication; abnormalities in eye contact and body language or deficits in understanding and use of gestures; including lack of facial expressions and nonverbal communication.
  • Deficits in developing, maintaining and understanding relationships- for example, difficulties adjusting behaviour to suit various social contexts; or difficulties in sharing imaginative play or in making friends.

Part B: Restricted, Repetitive, Patterns of Behaviour, Interests or Activities (at least 2 of the following)

  • Stereotyped or repetitive motor movements, use of objects, or speech, e.g., simple motor stereotypes (such as flapping hands), lining up toys or flipping objects, echolalia, idiosyncratic phrases.
  • Insistence on sameness, inflexible adherence to routines, ritualised verbal or non-verbal behaviour, e.g., extreme distress at small changes, difficulties with transitions, rigid thinking patterns, greeting rituals, need to take same route or eat same food every day.
  • Highly restricted fixated interests that are abnormal in intensity or focus, e.g., strong attachment to or preoccupation with unusual objects, excessively pursued interest.
  • Hyper- or hypo-reactivity to sensory input or unusual interests in sensory aspects of the environment e.g., apparent indifference to pain/temperature, adverse response to specific sounds or textures, excessive smelling or touching of objects, visual fascination with lights or movement).

Part B causes Part A

So let’s consider this from a different perspective. What if we look at the Part B diagnostic criteria and see if these can explain Part A. How would that work? Here are some examples taken from the DSM-5 Diagnostic criteria but looking at it in reverse.

Stereotyped, Repetitive Movements or speech

Stereotyped repetitive movements can be a variety of repetitive and uncontrolled movements from flapping hands, flicking fingers in front of eyes and flipping objects to head banging or picking at ones skin. When applied to speech this is repetition of words or blurting out random words that make no sense.

When speech does not make sense or is difficult to follow, communication and conversation is also difficult or impossible. If you are unable to have a conversation, then you will struggle to make friends.

On the face of it, minor repetitive movements such as flapping hands should not prevent conversation. For the autistic person, such movements may make it possible to have a conversation. But such movements can be very off putting and it would need a very tolerant, patient and understanding person to make the effort to communicate with and make friends with the person.

Sensory Issues

You do not have to be Autistic to have sensory issues. Estimates are that sensory issues affect around 90% of the autistic population. But these sensory issues vary widely from person to person. In many cases, sensory issues do not prevent communication and social interaction, but in other cases they do.

Issues occur when sensory issues interfere with hearing and understanding what is said. Such as sound discrimination issues and synaesthesia (eg seeing colours for sound can be very distracting and prevent understanding of what is said), Some autistic people struggle to tolerate being around other people because of sensory issues. Smell can be a factor in this as can the pitch of someone’s voice. Being oversensitive to emotion, can also be a factor.

If you are not able to hear properly or to be in the same place as people or be with certain people due to smells, noise, or emotion you will struggle to make friends. If you do make friends if will be difficult to maintain the relationship as you can not enjoy the things they do or go to they places they want to go due to sensory issues, you may then feel very left out or even disregarded. If you are left out, there will be much less opportunity to learn social skills.

Routines or ritualised patterns of behaviour

A very regimented life (ie difficulty with change) means that you thrive on routines and being organised in order to create structure and avoid anxiety. When this is the case, there is insufficient flexibility to be able to meet new people and get to know them. New people are too unpredictable, having to get to know a new person will be extremely difficult and stressful. Under these circumstances, there is no opportunity to learn social skills, never mind put them into practice.

Highly restricted, fixated interests

In order to do social interaction you need to show an interest in the lives of others or at least have a passing interest in what others are interested in. Some autistic people have their own specific interests that don’t always match the interests of the general population. Some autistic people like to speak only about their own interests and do not pay any attention or are very disinterested when others are describing theirs.

A very narrow range of interests results in huge gaps in your understanding of the world around you. The world of people will not make any sense. Any friendship has to be built on shared interests and conversation will be mainly about that interest.

Consider the ‘why’ not the ‘what’

If you accept that Part B of the diagnostic criteria causes Part A, then you are starting to understanding the ‘WHY’ and not just the the ‘WHAT’ (or symptoms). You are starting to understand the root of the symptoms and thus be able to think of strategies. The next step is to go deeper and to recognise that difficulty with change can be because of processing issues or because of visual issues, for example. Restricted interests can have processing issues as an underlying issue, or it could be a reflection of how an individual thinks and/or learns.

Of course, combinations of Part B criteria interact with each other and compound the issues, making part A symptoms more severe.

Understanding the WHY of an individual’s autism is much more valuable than a tick box exercise to determine a diagnosis. This is particularly pertinent for autism as there are essentially and infinite number of ways of being autistic. Without a thorough understanding of WHY, you are reduced to a trial and error approach to find appropriate interventions.

Aspiedent Can Help

Aspiedent has a service that helps people understand their autistic intelligence and in particular any other issues they may have including exposure anxiety. This is part of an autism profile (or Integrative Cognitive Profile). Sample autism profiles can be found on our website. Autism Profiles are potentially life changing for the better because they help both the person and those around them to understand their individual autistic difficulties.


If you are interested in having an autism profile, please do get in touch.