Signs and Symptoms of Autism Spectrum Disorders

Children can begin to show signs of autism spectrum disorder by the age of 3. However, because children with average or above average intelligence may be affected, the condition may not be noticed until later. When a child begins to develop socially and is placed in a school or playgroup setting, symptoms of autism spectrum disorder may become more apparent. In some cases, ASD is not diagnosed until adolescence (especially in girls).

Most experts agree that autism spectrum disorders vary greatly. In general, each child has his or her own unique set of symptoms. Children with ASD previously diagnosed as Asperger's syndrome usually have a combination of the following symptoms:

  • Above average memory skills
  • Average or above average vocabulary skills
  • Awkward, repetitive gestures, body postures or facial expressions
  • Below average handwriting
  • Difficulty understanding their feelings
  • Extreme difficulty with peer relationships and social situations
  • Inability to be empathetic
  • Inability to read non-verbal social cues and other people's feelings
  • Inability to sense other people's needs for personal space
  • Late development of motor skills or a lack of physical coordination
  • Obsessive interest in one topic which they may talk about excessively
  • Strong attachment to routine
  • Strong aversion to change or spontaneity
  • Unusual sensitivity to sound, light, or touch
  • Unusual speech patterns with regard to tone, pitch, or accents

Children may show any or all of these symptoms to various degrees. However, all children with ASD previously diagnosed as Asperger's syndrome generally have particular difficulty with social relationships.

Complications of Asperger's Syndrome

Children who have mild symptoms of autism spectrum disorder may simply be labeled as eccentric and not receive appropriate care and attention. It is also common for children with these disorders to become targets of teasing, ridicule, harassment, or bullying. Because of this, children with ASD are at increased risk for developing depression and other mental illnesses.

Diagnosis of Autism Spectrum Disorders

Parents who suspect their child may have an autism spectrum disorder should talk with his or her pediatrician about their observations and concerns. To rule out other conditions that may be causing the child's symptoms, the health care provider will perform a complete physical examination and may perform x-rays and blood tests. If no physical cause for the child's symptoms is found, he or she may be referred to a health professional who specializes in developmental disorders in children.

A thorough diagnosis and evaluation are important for determining the most effective treatments for the child. Diagnosis of autism spectrum disorder can be performed by one or more of the following health care professionals:

  • Child/adolescent psychiatrist
  • Child/adolescent psychologist
  • Developmental pediatrician
  • Pediatric neurologist

Diagnosis of the conditions involves taking a complete medical history of the child, usually based on the observations and recollections of the parents and other family members. Input from other caregivers or teachers who have had contact with the child are also helpful.

The medical history includes information about the pregnancy, the infancy period of the child, the child's early (pre-school) development, and the family's medical history. Specific information about the child's development of motor skills, language development, and interests; about how the child interacts socially with peers, siblings, and other family members; and about how the child expresses his or her feelings also is important.

In addition to a medical history, a communication assessment may be performed. This test is used to gather information about the child's communication skills, including the following:

  • Conversation skills (e.g., turn-taking, sensitivity to cues, ability to follow typical rules of conversation)
  • Formal language (e.g., vocabulary, sentence structure, comprehension)
  • Non-literal language (e.g., humor, irony)
  • Non-verbal communication (e.g., gestures, glances)
  • Speech (e.g., clarity, volume, pitch)

In children who have autism spectrum disorders, formal language may be an area of strength, and other forms of communication are usually areas of difficulty. In fact, the requirement of a delay in language development is no longer necessary for an ASD diagnosis.

According to the DSM-5, autism spectrum disorder diagnoses criteria are more thorough and more strict than in the past. Included are social/communication deficits, restricted interests, and repetitive behaviors. Additional classifications are based on severity levels (e.g, level 1, level 2, level 3) according to the amount of support needed.

Publication Review By: Stanley J. Swierzewski, III, M.D.

Published: 05 Jul 2007

Last Modified: 01 Sep 2015