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characteristics of AutismIn this post, I will talk about some of the Characteristics of Autism. The key objective for me is to provide you with an overview of the wide variety of characteristics that individuals with autism display on a day to day basis.  You will also learn how these characteristics are used to make a diagnosis.

Prevalence for autism spectrum disorder is increasing.  See below a graph from Autism Speaks on how the Autism rate is rising at endemic levels:

Autism Rates Rising

In March of 2013, the Centres for Disease Control and Prevention in the United States, released that incidence rates of autism are 1:50.

Understanding the Autism Diagnosis Process

First and foremost, it is important to understand how is Autism diagnosed.

The the Diagnostic and Statistical Manual of Mental Disorders , known as the DSM, which sets the guidelines for diagnosing psychiatric disorders has recently published and released it’s most current edition: the DSM-V (Real all about DSM 5 here).  The previous edition, the DSM-IV was released in 1994. This, in conjunction with the Autism Diagnostic Observation Schedule, is an extremely powerful tool for Autism diagnosis.

dsm 4 vs dsm 5

A comparison of DSM 4 Vs DSM 5

Autism is a spectrum disorder; the symptoms of individuals with ASD will fall on a continuum.  Under the DSM-IV the term spectrum related not only the range of disorders classified under the label but also that each individual diagnosed with an ASD can present with a range of characteristics.

With the DSM-V, Rett Syndrome has been removed from the manual.  All other disorders (Autism, Pervasive Developmental Disorder or PDD-NOS, Asperger’s Syndrome, and Childhood Disintegrative Disorder or CDD) have been subsumed and will be referred to as a single classification, Autism Spectrum Disorder. The term spectrum, in this case, refers to the wide range of characteristics found in individuals diagnosed with ASD. Having ASD presented as a spectrum disorder allows clinicians to account for the variation in symptoms and behaviors from person to person.

MUST READ: Autism Symptoms Checklist

As the DSM-V is newly released, you will continue to hear and see these terms, for example, PDD, PDD-NOS, and Asperger’s, as the autism community, adjust to the new classifications and diagnosing criteria.

Also, one of the most noted changes is that the two social domains in DSM-IV have been collapsed into one.  In the DSM4 social interaction and social communication were two different categories. In the DSM5 they are one.  The number of requirements for deficits under each diagnosing domain has also changed.  Some domains an individual will need less (for example, a language delay is no longer required for diagnosis), and in some domains, they will require more.

Under the DSM-V criteria, individuals with ASD must show symptoms from early childhood, even if those symptoms are not recognized until later. This criteria change encourages earlier assessment and screening of Autism but also allows people whose symptoms may not be fully recognized until social demands exceed their capacity to receive the diagnosis. It is an important change from DSM-IV criteria, which was geared toward identifying school-aged children with autism-related disorders, and was not as useful in diagnosing younger children, for example, preschool children.

Understanding the Characteristics of Autism

Not all children with a diagnosis of Autism Spectrum Disorder are the same.  They are their own person, and will have their own individual Autism characteristics. Autism spectrum disorder is a neurodevelopmental disorder that has 2 core areas of characteristics (plus additional criteria applicable to both areas).

  • The first core area has 2 subsections:

The first relates to impairments in Social Interaction – can range from not being able to play with toys functionally to not being able to ask a friend to play even though the child may have words.

The second, relates to deficits in Social Communication – can range from not having any verbal language and using other means to communicate, for example using pictures, or gestures, or sign language, to having verbal communication however having difficulty in comprehending others perspectives or knowing how to ask a friend to play

  • The second core area relates to restricted and repetitive patterns of behaviour, interests, or activities.  This can range from flapping of the arms, rocking back and forth, to using toys or objects in a manner not intended for.  For example, a child may turn a toy truck over and only spin the wheels, instead of driving it around on the floor. Even echolalia in Autism and Tourette’s syndrome falls under this category.
  • The third section relates to additional criteria relating to the two core areas as described: Symptoms must be present in the early developmental period (but may not fully manifest until social demands exceed limited capacities, or symptoms may be masked by learned strategies later in life).  Overall, symptoms cause clinically significant impairment in social, occupational, or other important areas of current functioning, These disturbances are not better explained by intellectual disability (such as intellectual developmental disorder) or a global developmental delay.

Helpful Resources:

Child Development Milestones
Pathways© Sensory Motor Checklist

The DSM, which is published by the American Psychiatric Association provides both a common language and standard criteria for the classification of mental disorders.

As it relates to Autism, there are 3 main areas required for diagnosis:

1) Social communication, and social interaction

2)Restrictive, repetitive behaviours, interests, or activities  and

3)Additional criteria

Social Deficits with Autism

First, let’s talk about the social deficits. All individuals must have or have had persistent deficits in social communication and social interaction across contexts, not accounted for by general developmental delays, and manifested by all 3 of the following:

  • Deficits in social-emotional reciprocity; behaviours range from abnormal social approach and failure of normal back and forth conversation, to reduced sharing of interests, emotions, or affect; and involves the failure to initiate or respond to social interactions.
  • Deficits in nonverbal communicative behaviours used for social interaction, ranging from poorly integrated- verbal and nonverbal communication to abnormalities in eye contact and body-language, or deficits in understanding and using gestures, to a total lack of facial expression and non-verbal communication.
  • Deficits in developing, maintaining and understanding relationships; behaviours here range from having difficulties adjusting their behaviour to suit various social contexts, to having difficulties in sharing imaginative play or in making friends; or an absence of interest in peers.[/fusion_li_item]

Autism and communication deficits

Eye Contact

Individuals with autism may have difficulty with maintaining eye contact, may have difficulty reading and using facial expressions, body posture and gestures.  For example, they may not respond to a “stare” that means to stop or to tone of voice.  This should not be interpreted as defiance, rather it’s that sometimes they don’t recognize what it means.


Misinterpreted as having no relationships – children with ASD often have very strong, connected relationships with parents and primary caregivers, but they struggle with making relationships with their peers.  Lack of shared or joint attention may be the core deficit.  They don’t look to other’s to share the experience, they don’t bring others attention to their activity; for example, they don’t say “hey, look at what I am doing) and therefore they struggle to learn social behaviours.


Children learn how to behave socially by watching others.  Children with ASD struggle with knowing that others may have a different point of view or perspective, may know or believe different things and may have different experiences.

This leads to difficulty understanding and predicting others behaviour and a lack of awareness of the impact of their behaviour on others.  They may speak in the same manner to people of all ages, with different levels of familiarity – for example, the bus driver that they don’t know in the same way they talk to a familiar family member).

Deficits in the social domain cause the individual with autism to have the inability to: Read the listener’s level of interest, detect a speaker’s intended meaning, understand “unwritten rules” or conversations, and anticipate what others might think of one’s actions.

Having a conversation

  • They may not notice when people are talking to them, therefore may not respond
  • Though they know how to talk, they may have difficulty “joining in” on the conversation
  • Some individuals with ASD may have poor eye contact or may have difficulty making eye contact at all

Non-verbal communication

They may have difficulty understanding gestures; for example, hand gestures such as waves hello or waves goodbye, or a thumbs up, understanding body language  such as shoulder shrugs, nods of approval, shaking of head in disapproval, hands crossed over one’s chest showing disinterest, smiles, etc..  As these cues may not be understood, individuals with ASD may not respond appropriately.

Routine Oriented

  • Some individuals with ASD are overly dependent on routines
  • Some individuals with ASD have a need for things to always be the same. They don’t like changes or surprises.

Examples include dressing in the same order each day going to school or work on the same route.  They may do the same activities on same days. For example, Mondays is always play gym, Tuesday is swimming, Wednesday is always a trip to the library, etc.

Making Friends

  • Children with ASD may not relate to their own age group, and sometimes prefer the company of adults.
  • Individuals with ASD may have some difficulty controlling or displaying their emotions and excitement in an appropriate manner and this can affect their social interaction with their peers.

Behavioral Deficits with Autism

behavioral characteristics of Autism

We are now going to move on to the behaviour section of the diagnostic criteria. All individuals with ASD must have or have had restricted, or repetitive patterns of behaviour, interests, or activities as manifested by at least two of the following 4 domains:

  • Stereotyped or repetitive motor movements, use of objects, or speech.  Examples include repetitive simple motor movements like twirling ones hair, lining up toys, flipping objects over, echolalia, or use of idiosyncratic phrases.
  • Insistence on sameness, inflexible adherence to routines, or ritualized patterns of verbal or nonverbal behavior.  Examples include, extreme distress at small changes, difficulties with transitions, rigid thinking patterns, or greeting rituals, and the need to take the same route or eat same foods every day).
  • Highly restricted, fixated interests that are abnormal in intensity or focus. For example, individuals with ASD may have strong attachment to, or preoccupation with unusual objects like fans or washing machines). Individuals with ASD may have  excessively circumscribed or perseverative interests).
  • The last domain deals with Hyper-or hypo-reactivity to sensory input or unusual interest in sensory aspects of the environment.  For example, having an indifference to pain or temperature, adverse response to specific sounds or textures, excessive smelling or touching of objects, visual fascination with lights or movement.

Below are some of the challenges observed in behavioral characteristics of Autism – primarily related to restricted and repetitive behavior, activities, interests?


  • Many people with ASD display restricted patterns of interests, therefore, may talk about or focus on only one thing, for example,  trains, or 1 particular piece of music.
  • Some individuals with ASD have unusual interests or habits, for example, obsessive interest in washing machines, motors, or a particular cartoon character.

Motor movements

  • People with autism may repeat behaviours over and over again, such as spinning, rocking, staring, finger flicking, hitting themselves, grinding teeth.
  • Individuals with ASD may display unusual postures when interacting with others; they may walk and move in a manner that is not common.


  • Children with ASD may start to develop appropriate language and then regress. They may develop language very slowly, or they may never develop vocal speech communicating only by gestures like pointing or reaching.
  • Some individuals with ASD have echolalia (this is repeating something they just heard in a non-functional manner); for example, if you ask them, “How are you today?” the individual with ASD will respond “How are you today?” instead of answering the question.

Sensory Integration

Individuals with ASD may have hypersensitivity or hypo-sensitivity to sounds, sights, touch, taste and smells. For example, fire alarms, school bells, a crowded mall, tags on clothing, smells in a restaurant all may cause distress for the individual with ASD.

MUST READ: What is Sensory Integration Disorder & Sensory Integration Disorder Symptoms

Additional Autism Characteristics

In addition to the criteria for the social and behaviour domains, there are additional criteria required for diagnosing an individual with autism spectrum disorder.

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

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

E. These disturbances are not better explained by intellectual disability or a global developmental delay. Intellectual disability and autism spectrum disorder frequently co-occur; to make a comorbid diagnosis of autism and intellectual disability, social communication must be below that expected for the individual’s general developmental level.

This speaks to the fact that intellectual disability is not automatically associated with ASD. The individual must demonstrate more severe social communication deficits, over and above those expected from just having an intellectual disability.  It must be demonstrated that the deficits are in the ASD specific areas, and not just an overall delay in all areas (otherwise known as a global developmental delay).

The exact cause of autism spectrum disorder is unknown.  Researchers around the world are conducting studies to try and isolate the particular causes of this disorder.  Results from current research strongly suggest that autism has a neurological, or genetic, or biological/environmental basis for its manifestation.

Applied Behaviour Analysis is the only proven intervention to be deemed effective when working with individuals with autism.  ABA focuses on the observable relationship of behaviour to the environment.  By looking at this relationship, the methods of ABA can be used to change behaviour.  Though you may hear of a variety of other strategies to help individuals with autism, none have the research behind it to prove their efficacy.

ABA is Applied, meaning it targets behaviours that are socially significant.

ABA is Behavioural, studying observable, measurable events.

And ABA is Analytic as it demonstrates reliable factors controlling behaviour.

ABA will help to:

  • Teach new skills
  • Reduce maladaptive behaviours

MUST READ: What is Applied Behavior Analysis?

I hope you found this post on characteristics of Autism quite helpful. Here are some additional resources that you might find useful:

Join the discussion One Comment

  • Mary L Mockford says:

    The article was most informative. I am researching resources for a relative who has an adult child displaying multi-autistic behaviors. Who is the best to make a definitive diagnosis and give the father info on associations, support groups etc.? The physical area is Seatle, WA.

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