Common Signs of Autism Spectrum Disorders

Autism is a highly variable brain development disorder that first appears during infancy or childhood, and generally follows a steady course. Overt symptoms gradually begin after the age of six months, become established by age two or three years and tend to continue through adulthood, although often in more muted form. It is distinguished not by a single symptom, but by a characteristic triad of symptoms: impairments in social interaction; impairments in communication; and restricted interests and repetitive behavior. Other aspects, such as atypical eating, are also common but not essential for diagnosis. Autism's individual symptoms occur in the general population and appear not to associate highly, without a sharp line separating pathologically severe from common traits.

Red Flags

The following signs may indicate a child is at risk for an autism spectrum disorder, and is in need of an immediate evaluation.

In clinical terms, there are a few “absolute indicators,” often referred to as “red flags,” that indicate that a child should be evaluated. For a parent, these are the “red flags” that your child should be screened to ensure that he/she is on the right developmental path.

Red Flags of Autism Spectrum Disorders:
If your baby shows two or more of these signs, ask your pediatrician for an immediate evaluation.

Impairment in Social Interaction:

  • Lack of appropriate eye gaze
  • Lack of warm, joyful expressions
  • Lack of sharing interest or enjoyment
  • Lack of response to name

Impairment in Communication:

  • Lack of showing gestures
  • Lack of coordination of nonverbal communication
  • Unusual prosody (little variation in pitch, odd intonation, irregular rhythm, unusual voice quality)

Repetitive Behaviors & Restricted Interest

  • Repetitive movements with objects
  • Repetitive movements or posturing of body, arms, hands, or fingers

Source: Wetherby, A., Woods, J., Allen, L., Cleary, J., Dickinson, H., & Lord, C. (2004). Early indicators of autism spectrum disorders in the second year of life. Journal of Autism and Developmental Disorders, 34, 473-493. Based on research at the Florida State University FIRST WORDS® Project

Infants—Infants with autism show less attention to social stimuli. They smile and look at others less often, and respond less to their own name.

Toddlers—Toddlers with autism differ more strikingly from social norms. They experience less eye contact and turn-taking and are more likely to communicate by manipulating another person's hand.

Pre-school—Three- to- five-year-old children with autism are less likely to exhibit social understanding. They may approach others spontaneously, exhibit imitating behaviors, turn-taking and nonverbal communication. Although they can form attachments to their primary caregivers, they will likely display moderately less attachment security than most children of the same age range. However, this feature may not present in children with higher mental development or less severe ASD.

Older Children and Adults—Older Children and Adults with ASD perform worse on tests of face and emotion recognition. Contrary to common beliefs, children with autism do not prefer being alone. Making and maintaining friendships often proves to be challenging but for them, the quality of friendships, not the number of friends, predicts how lonely they feel. Functional friendships, such as those resulting in invitations to parties, may affect their quality of life more deeply.

Autism is characterized by what is clinically described as “deficits in social reciprocity.” Social reciprocity may include a range of back-and-forth actions, including gestures, sounds, attention and conversation. Ritualistic and/or obsessive behaviors may also be present.

In fact, individuals with autism display many forms of repetitive or restricted behavior, which the Repetitive Behavior Scale-Revised (RBS-R) categorizes as follows:

No single repetitive behavior seems to be specific to autism, but only autism appears to have an elevated pattern of occurrence and severity of these behaviors.

Other characteristics may include uncontrollable temper tantrums, drastic resistance to change and extreme over- or under-sensitivity to sights and sounds. The number of people known to have autism has increased dramatically since the 1980s, partly due to changes in diagnostic practice; the question of whether actual prevalence has increased is unresolved. The symptoms are varied, but one thing is clear ... the earlier a child is diagnosed and begins receiving treatment services, the better the prognosis for the child.

In many cases, you will find one or more overlapping disorders present in children with autism, including anxiety, mood regulation, depression, allergies, gastrointestinal disorders, immune dysfunction, hyperactivity, obsessive behaviors, seizures. On their own, none of these disorders would indicate a presence of an autism spectrum disorder, but many children with ASD will have one or more of these co-morbid symptoms. In fact, about 25% of children with autism will experience seizures during their lifetime. Before the diagnosis of ASD is given, ask your doctor to rule out the following disorders: