What is Autism?

Autism Spectrum Disorder (ASD) is classified as a neurodevelopmental disorder according to the Diagnostic and Statistical Manual of Mental Disorders (DSM 5). This means that ASD is regarded as a disorder that originates in the brain and is most often diagnosed during early childhood, typically before the age of 3.

ASD occurs on a spectrum, indicating that individuals with ASD can present differently from one another. Some deficits and excesses seen in ASD are often similar, but the extent thereof can vary. For example, a child may have a few restrictive and repetitive behaviours that do not cause too much distress versus another child’s restrictive and repetitive behaviours that cause significant distress to the child when not carried out.

Diagnostic Criteria

According to the DSM 5, there are certain criteria that must be met to be diagnosed with ASD (American Psychiatric Association, 2013):

A. Persistent deficits in social communication and social interaction across multiple contexts, as manifested by the following, currently or by history:

    1. Deficits in social-emotional reciprocity, ranging, for example, from abnormal social approach and failure of normal back-and-forth conversation;
      to reduced sharing of interests, emotions, or affect; to failure to initiate or respond to social interactions.
    2. Deficits in nonverbal communicative behaviours used for social interaction, ranging, for example, from poorly integrated verbal and nonverbal communication; to abnormalities in eye contact and body language or deficits in understanding and use of gesture; to a total lack of facial expressions and nonverbal communication.
    3. Deficits in developing, maintaining, and understanding relationships, ranging, for example from difficulties adjusting behaviour to suit various social contexts; to difficulties in sharing imaginative play or in making friends; to absence of interest in peers.

Severity is based on social communication impairments and restricted, repetitive patterns of behaviour.

B. Restricted, repetitive patterns of behaviour, interests, or activities, as manifested by at least two of the following, currently or by history
(examples are illustrative, not exhaustive):

    1. Stereotyped or repetitive motor movements, use of objects, or speech (e.g. simple motor stereotypies, lining up toys or flipping objects, echolalia, idiosyncratic phrases).
    2. Insistence on sameness, inflexible adherence to routines, or ritualized patterns of verbal or nonverbal 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).
    3. Highly restricted, fixated interests that are abnormal in intensity or focus (e.g. strong attachment to or preoccupation with unusual objects, excessively circumscribed or perseverative interests).
    4. Hyper- or hyporeactivity to sensory input or unusual interest 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).

Severity is based on social communication impairments and restricted, repetitive patterns of behaviour.

C. Symptoms must be present in the early developmental period (but may not become fully manifest until social demands exceed limited capacities,
or may be masked by learned strategies in later life).

D. Symptoms cause clinically significant impairment in social, occupational, or others important areas of current functioning.

E. These disturbances are not better explained by intellectual disability (Intellectual developmental disorder) or
global developmental delay. Intellectual disability and autism spectrum disorder frequently co-occur; to make comorbid diagnoses of autism spectrum disorder and intellectual disability, social communication should be below that expected for general developmental level.

Severity Levels


Requiring Support

Social communication – without support deficits in social communication cause noticeable impairments, difficulties initiating social interactions, clear examples of atypical/unsuccessful responses to social overtures of others. Appearance of decreased interest in social interactions, e.g. full sentence capacity and engages in communication but to-and-fro conversation with others fail. Attempts to make friends are odd and typically unsuccessful.

Restricted, repetitive behaviours – inflexible behaviours cause functional interference across contexts. Difficulties in changing/switching between behaviours. Independence is hampered by problems of organization and planning.


Requiring Substantial Support

Social communication – Marked deficits in verbal and nonverbal social communication skills; social impairments apparent even with supports in place; limited initiation of social interactions; and reduced or abnormal responses to social overtures from others. E.g. simple sentences, limited to narrow special interests, noticeably odd nonverbal communication.

Restricted, repetitive behaviours – Inflexibility of behaviour, difficulty coping with change, or other restricted / repetitive behaviours appear frequently – obvious to casual observer. RRBs interfere with functioning across various contexts. Distress and/or difficulties changing focus or attention.


Requiring very Substantial Support

Social communication – Severe deficits verbal and nonverbal social communication skills causing severe impairments in functioning, very limited initiation of social interactions and minimal response to social overtures from others. E.g. few words of intelligible speech, rarely initiates interaction, if does – makes unusual approaches to meet needs only and responds to only very direct social approaches.

Restricted, repetitive behaviours – Inflexibility of behaviour, extreme difficulty coping with change, or other restricted / repetitive behaviours markedly interfere with functioning in all spheres. Great distress / difficulty changing focus or action.

What does ASD look like?

When observing an individual with ASD, the following may be present:


Delays In:

• Language • Play • Social Skills • Academics • Motor Skills • Perceptual Skills • Etc •


Behavioural Issues:

• Repetitive Behaviours • Non-Compliance • Tantrums and Meltdowns • Aggression • Self-Injury •


Sensory Integration Difficulties:

• Auditory • Visual • Tactile • Proprioceptive • Oral • Vestibular •

What are some of the first symptoms of ASD?

Who Diagnoses ASD?

If your child shows any symptoms of ASD, a specialist who treats children with autism spectrum disorder, such as a pediatric psychiatrist or psychologist, pediatric neurologist, or developmental pediatrician, can be contacted for an evaluation.

Making a diagnosis may be difficult because ASD varies widely in symptoms and severity. There isn’t a specific medical test to determine the disorder.
Instead, a specialist may:

  • Observe your child and ask how your child’s social interactions, communication skills and behavior have developed and changed over time
  • Give your child tests covering hearing, speech, language, developmental level, and social and behavioral issues
  • Present structured social and communication interactions to your child and score the performance
  • Use the criteria in the Diagnostic and Statistical Manual of Mental Disorders (DSM-5), published by the American Psychiatric Association
  • Include other specialists in determining a diagnosis
  • Recommend genetic testing to identify whether your child has a genetic disorder such as Rett syndrome or fragile X syndrome

Can Autism be Cured?

No cure exists for autism spectrum disorder, and there is no one-size-fits-all treatment.
The goal of treatment is to maximize your child’s ability to function by reducing autism spectrum disorder symptoms and supporting development and learning. Early intervention during the preschool years can help your child learn critical social, communication, functional and behavioral skills.

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