What is Autism?

Autism Definition (Education)

This information is extracted from the 2004 compliance plan for Missouri, a plan designed to meet the requirements of PL94-142 as amended by PL108-446 (IDEA-2004)

"Autism" means a developmental disability significantly affecting verbal or nonverbal communication and social interaction, generally evident before age 3, that adversely affects a child's educational performance. Other characteristics often associated with autism are engagement in repetitive activities and stereotyped movements, resistance to environmental change or change in daily routines, and unusual responses to sensory experience. * [Bolding added by Project ACCESS] [See #4 below] [OSEP regulations 300.7(c)(l)(i)]

The term does not apply if a child's educational performance is adversely affected primarily because the child has an emotional disability as defined in this document [OSEP regulations 300.7(c)(l)(i)]. A child who manifests the characteristics of autism after age 3 could be diagnosed with autism if the criteria are satisfied.** [See #3 below], OSEP regulations 300.7(c)(l)(i)].

Criteria for Initial Determination of Eligibility

A child displays autism when:

Through evaluation that includes a review of medical records, observation of the child's behavior across multiple environments, and an in-depth social history, the following behaviors are documented:

  1. Disturbances of speech, language-cognitive, and nonverbal communication: The child displays abnormalities that extend beyond speech to many aspects of the communication process. Communicative language may be absent or, if present, language may lack communicative intent. Characteristics may involve both deviance and delay. There is a basic deficit in the capacity to use language for social communication, both receptively and expressively.
  2. Disturbances of the capacity to relate appropriately to people, events, or objects: The child displays abnormalities in relating to people, objects, and events. There is a basic deficit in the capacity to form relationships with people. The capacity to use objects in an age appropriate or functional manner of exhibiting rigidity in routines.

The condition adversely affects the child's educational performance.

The autism is not a result of an emotional disability as defined in this document.

Other behaviors which the child may exhibit include:

  1. Disturbances of developmental rates and sequences: The child may also exhibit delays, arrests, or regressions in physical, social, or learning skills. Areas of precocious skill development may also be present, while other skills may develop at normal or extremely depressed rates. The order of skill acquisition frequently does not follow normal developmental patterns [See bold section 300.7(ii) above]. 
  2. Disturbances of responses to sensory stimuli: The child's behavior may also range from being hyperactive to being unresponsive to people and objects in their environment and can alternate between these two (2) states over periods ranging from hours to months. Disturbances may be apparent in auditory, visual, olfactory, gustatory, tactile, and kinesthetic responses. The child may respond to stimulation inappropriately and in repetitive or nonmeaningful ways [See bold section 300.7(c)(l)(i) above].

*OSEP regulations 300.7(c)(l)(i). Project ACCESS has bolded this sentence for clarification purposes. According to OSEP, this sentence in the federal definition indicates that disturbances of responses to sensory stimuli essentially becomes criteria #4.

**OSEP regulations 300.7(ii). This sentence in the OSEP regulations essentially means that disturbances of developmental rates and sequences becomes criteria #3.

Italics above are added by Project ACCESS for training purposes only. They are not included in the Missouri State Plan for Compliance to PL108-446 (IDEA-2004), but are references to explanatory OSEP regulations. They are intended to explain issues of concern to educators and diagnosticians in Missouri.

Facts about autism

In 2020, the Centers for Disease Control and Prevention (CDC) released a new study stating that autism now affects 1 in every 54 American children, "reported to occur in all racial, ethnic, and sociaoeconomic groups", with boys four times more likely to be identified than girls.

The Centers for Disease Control and Prevention's Autism and Developmental Disabilities Monitoring (ADDM) Network now estimates the prevalence of autism spectrum to be one in fifty-four children.  The estimated prevalence has increased from 1 in 150 children in the CDC's 2007 report to 1 in 110 children in 2009, 1 in 88 children in 2012 and 1 in 68 children in the 2014 report.  You can read more about how the Disabilities Monitoring Network arrived at their figures on the CDC website, as well as a summary of Data & Statistics on Autism Spectrum Disorder on a separate CDC webpage. 

"A Snapshot of Autism Spectrum Disorder in Missouri" is also available on the CDC website at the following link:  ASD in Missouri