Individuals with autism spectrum disorder display (A) restricted or repetitive-type behaviors and (B) impairments in social communication that arise during the early developmental period. Manifestations of the disorder vary by severity of the autistic symptoms, as well as by the child’s developmental level and chronological age, justifying the term “spectrum” in the disorder’s new name.

Criterion A Symptoms: Communication Deficits

Children with autism spectrum disorder display deficits in both verbal and nonverbal communication. Failure or difficulty engaging emotionally with others is a hallmark symptom of autism. Children generally have difficulty making eye contact, understanding subtleties of conversation (for example, body language), empathizing with the emotions of others, and expressing their own thoughts and feelings. Severity of these deficits can range from problems understanding gesturing in conversation to lack of attempts to initiate or respond to social interaction altogether. Also common, children with autism often have difficulty adjusting behavior and facial expressions to meet specific social circumstances. Verbal deficits involve problems with spoken language and conversing appropriately with others. Deficits vary in severity, from complete lack of speech to overly literal speech. To meet diagnostic criteria, communication problems must be persistent and pervasive across contexts.

Criteria B Symptoms: Abnormal behaviors

Restricted and/or repetitive-type behaviors make up the B criteria autism symptoms. An individual must display two of the following: stereotyped behaviors, overly rigid routines, highly specific interests or preoccupations, and hypersensitivity to sensory stimuli in the environment.

Stereotyped movements or behaviors with objects can involve hand flapping, finger flicking, coin spinning, lining up objects, and other repeated actions. Stereotyped phrases or words are also common, such as parroting others’ speech.

Rigidity involves insistent adherence to specific daily routines, methods, or rules, as well as resistance to change. For example, a child may insist on a certain way to open a package of food, and may be very upset if disrupted or if the packaging of the item itself has changed. Excessive adherence is often accompanied by narrowed fixation for certain interests or objects. For example, a child may prefer to play solely with a household pan or a single toy over all other objects. Narrowed focus on certain activities and restrictive food intake are also common.

Over- or under-sensitivity to stimuli in the environment makes up the last behavioral symptom. A child with hypersensitivity may show an extreme reaction that is out of proportion to the sensation. For example, a child may cry out and cover their ears when in a room where multiple conversations are occurring. A child with hyposensitivity may be less averse to physical pain than others. In other cases, children may show a strong preference or display fascination with certain textures, smells, tastes, sights, or sounds. For example, while one child will excessively smell or touch an object, another may fixate on things that spin colorfully.

A clinician will rate a child’s current severity based on the amount of daily assistant required by the individual. For example, least severe would be noted as “requiring support”, while most-severe would be noted as, “requiring very substantial support.”

The clinician establishing the diagnosis will also note whether the disorder is accompanied by intellectual and/or language impairment or with catatonia.

DSM-5 code 299.00

Note: Autistic disorder, Asperger’s, childhood disintegrative disorder, & Rett’s disorder have been subsumed under the name “autism spectrum disorder” in the 2013-publishedFifth Edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5).