Autism Definition And The Definitions Of Autism Spectrum Disorders

Autism Can Sound Scary, But When It's Diagnosed You'll Have More Answers.
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The Definition of Autism

The definition of autism from Merriam Webster's Dictionary is - a variable developmental disorder that appears by age three and is characterized by impairment of the ability to form normal social relationships, by impairment of the ability to communicate with others, and by repetitive behavior patterns. While this definition is accurate, there is more to Autism than communication impairment and repetitive behaviors.

The definition of autism has grown to include a large collection of symptoms and behavior patterns. As time marches on, more and more information gathered through clinical studies and research, is decoding the causes behind autism; is it hereditary, environmental, or a combination of both? The answers to this question is not cut and dry, it seems that causes can be hereditary and environmental. The definition of autism is broad and it is defined by the causes, symptoms, and impairments exhibited.

Psychiatry and psychology use specific guidelines to define autism. These guidelines cover all the behaviors and impairments that are present when an individual is autistic. Even though autism has a definition and there are set guidelines for diagnosing autism, many cases fall outside of the classic definition. When an individual exhibits behaviors and impairments that are typical and atypical, the behaviors and impairments are then compared to those on the autism spectrum.

Autism Symptom Definitions


Autism is a neurodevelopmental disorder and typical symptoms can vary in intensity. Symptoms can begin to show as early as infancy but it becomes more apparent around the age of 3. Autistic symptoms are defined by three main characteristics.

  • Impairment of communication skills
  • Impairment of social skills
  • Repetitive behavior patterns

An impairment in communication skills becomes noticeable around the age of three. At this age, children can communicate with others verbally, through gestures, and through behaviors, those with autism show varying impairment in these communication skills. Children with autism do not use as many words or gestures to communicate, may not make eye contact and they may repeat words rather than use words to communicate.

Impairment of social skills can be noticed at a young age. Children with autism do not initiate social interaction with their peers or adults. Sharing and taking turns is a problem because they do not communicate their desires and they may not acknowledge the presence of others. Using simple gestures to communicate socially is diminished, they may not point to objects or respond when other point.

Autism symptoms also include repetitive behavior patterns. A child with autism will engage in repetitive behaviors, and these behaviors are defined using the Repetitive Behavior Scale-Revised or RBS-R for short. The following is the list of repetitive behaviors defined using this scale:

  • Repetitive movements - rocking, head rolling, and hand flapping
  • Compulsive behaviors - lining up items in specific orders, repetitive hand washing, or any other behavior performed according to specific rules
  • Resistance to change - a strong reaction to a change in their environment such as moving furniture or going to school using a different route, and a refusal to be interrupted
  • Ritualistic behavior - preference for unvarying daily routines such as meal schedules, dressing times and dressing patterns i.e. shirt first, then pants…or socks first etc.
  • Restricted interests - fixations with specific interests that are abnormal in theme or focus, such as a fixation with a specific toy, game, or television show
  • Self- injury - behaviors such as head banging, hair tugging, or hand biting

The RBS-R scale does not define any specific activity or self-injurious behavior as autistic, it is the degree of repetition and severity of the activity that is defined. Autistic behaviors vary from individual to individual and the degree of repetition or severity of the behavior is used to understand the individual.

This scale helps professionals assess the symptoms of autism and work toward providing treatment and therapy. Professional therapy for individuals with autism is important for quality of life. Autism cannot be cured but behaviors on the RBS-R scale such as tantrums or self-injury can be lessened with the proper therapy. Individuals with autism also benefit from the specialized care of a licensed therapist; compulsive behaviors, resistance to change, and restricted interests can be worked with and caregivers can gain invaluable insight and support.

What is the Autism Spectrum?

Autism Can Sound Scary, But When It's Diagnosed You'll Have More Answers.
A Good Online Therapist Knows How to Treat Autism Best.


The autism spectrum was developed and used to define and encompass atypical as well as typical autism in the DSM - 5. The DSM - 5 is the psychological diagnosis manual used to diagnose psychological disorders. Professionals use this manual to define and diagnose mental disorders. The DSM - 5 includes autism spectrum disorders so atypical disorders such as Asperger's syndrome, pervasive developmental disorder not otherwise specified, and childhood disintegrative disorder are now understood as being autistic in nature.

Autism spectrum disorders have the same diagnostic symptoms as autism itself but they may exhibit other symptoms too. High functioning autism, low functioning autism, and a wide range of neurodevelopmental disorders all fall under the title of autism spectrum disorders. This classification negates the need to separate the many different degrees and presentations of autistic behavior.

The autism spectrum includes all the variations autism can display, but it is specific and does not include any disorders that do not have both main symptoms of autism; social communication problems and repetitive/restrictive problems. Autism spectrum was developed to include all the varying neurodevelopmental impairments that can be found in those with autism. Because neurodevelopmental impairments can vary significantly in those with autism, it was difficult to define and diagnose effectively. The DSM - 5 uses autism spectrum to encompass all the varying degrees of autism, this makes diagnosis more effective.

Defining Autism Spectrum Disorders

Although autism spectrum disorders may have specific names such as Asperger's syndrome and pervasive developmental disorder, they still exhibit autistic symptoms and behaviors that are significant and define the condition itself. Defining individual disorders that fall under the autism spectrum provides more insight into specific behaviors and provides specifics that caregivers and professionals can use to care for those with the disorder.

A person must present with the following symptoms to be diagnosed with an autism spectrum disorder:

  • Impairment of social communication
  • Repetitive and restrictive behaviors

These two diagnostic symptoms can present in many ways, but all the behavior still falls under these two main symptoms. For instance: an individual may have an IQ over 50 and suffer with social communication difficulties and restrictive behaviors, or have a large vocabulary but still have trouble communicating socially. The definition of autism spectrum disorders is broad enough to encompass many different degrees of impairment and a variety of behaviors without excluding a diagnosis of autism because the individual presents with symptoms of Asperger's syndrome; regardless it is still a form of autism.

Asperger's syndrome is a disorder on the autism spectrum. Those with Asperger's struggle with social skills, focus on and obsess about a specific subject, but they have normal intelligence. Asperger's is on the autism spectrum because it has similar symptoms as autism but some symptoms are different. Asperger's does not have its own diagnosis in the DSM - 5 anymore, it is grouped under autism spectrum disorder but many still refer to it as Asperger's syndrome.

No matter what, the definition of autism spectrum disorder includes both impairment in social communication and repetitive/restrictive behaviors. These two symptoms define these disorders and help separate the diagnosis from similar mental disorders such as pragmatic communication disorder or PCD. PCD presents with communication problems, both verbally and written, but it lacks the repetitive and restrictive behaviors of an autism spectrum disorder.

Diagnosis of autism may still include descriptive explanations such as High functioning, or low functioning, but regardless, they are still understood as falling under the diagnosis of autism. A higher IQ may mean that an autistic individual can function at a higher level than an individual with a lower IQ, but both have autism. Autism spectrum has cleared up what it means to be autistic and has made diagnosis easier.


Defining autism spectrum disorders relies on defining the vary degrees of autism present in an individual. The better the symptoms are defined, the better the long-term outcome. An individual diagnosed with autism spectrum disorder that is defined by a higher IQ will have a better chance at living an independent life. This is important to therapy, an individual like this would benefit more from therapy that focuses on acquiring independent life skills.

Autism spectrum disorder can help define the degree to which an individual exhibits autistic symptoms. Because autism spectrum disorder assumes there are differences in the degree to which an individual will exhibit specific symptoms. Those with Asperger's syndrome are high functioning and they require different therapy than those with extreme restrictive symptoms.

Before the DSM - 5 included the new definition of autism spectrum disorder, all the degrees of autism were lumped together. Autism is not the same for everyone, allowing for different degrees in the symptoms has opened new doors for treatment and therapy. Defining autism is not about understanding the repetitive behavior or the lack of social communication skills, it is about providing support and treatment specific to the needs of the individual.

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