Many children with autism spectrum disorder (ASD) may show developmental differences throughout their infancy, especially in social and language skills. Read on to learn more from the American Academy of Pediatrics about the early signs of ASD.

Because children with ASD usually sit, crawl, and walk on time, subtler differences in the development of gestures (that is, pointing), pretend play, and social language often go unnoticed by families and doctors. In addition to noticing delays in spoken language, families may notice differences in interaction with peers.

Delay or Lack of Joint Attention

One of the most important developmental differences between children with ASD and children without ASD is a delay or lack of joint attention. Joint attention is looking back and forth between an object or event and another person and connecting with that person. It is a building block for later social and communication skills. Engaging in many back-and-forth social interactions, such as exchanging a lot of emotional expressions, sounds, and other gestures, is called reciprocal social interaction. Delays in joint attention skills are found in most children with ASD and rarely seen in children with other types of developmental problems. Thus, a delay or lack of joint attention is thought to be among the most characteristic developmental differences in children with ASD. There are several stages of joint attention. Children with ASD usually show delays or absent skills at every stage.

Subtle milestones in use and understanding of gestures occur at the following times:

• At 10 to 12 months. Most typically developing children will immediately look in the direction of an object to which a parent is pointing at 10 to 12 months. They will then look back at the parent and mimic the parent’s expression, usually a smile. Children with ASD may appear to ignore the parent. This can cause parents to worry about their child’s hearing.
• At 12 to 14 months. Most children are able to point to out-of-reach objects that they want by 12 to 14 months. A child with ASD may instead take a parent’s hand and lead the parent to the object without making eye contact. Sometimes the child may even place the parent’s hand onto the object itself.
• At 14 to 16 months. Most children point at objects they find interesting by 14 to 16 months. Children will look back and forth between an object and a parent to make sure that the parent is tuned-in to what they are looking at. A child with ASD will often point to an object because he wants the parent to get it for him, not because he wants the parent to enjoy looking at an object together.

Language Delays

Almost all children with ASD show delays in nonverbal communication and spoken language. They may have words that they use to label things but not to request things. They may use words for objects first, before using words for people or family members. Most young children go through a phase during which they repeat what they hear. Children with ASD may repeat what they hear for a longer period and may repeat dialogue from movies or conversations with the tone of voice in which they heard them. Children later diagnosed as having higher-functioning ASD will seem to have met language milestones during the toddler years, but use of language may be abnormal or overly sophisticated or mature (“little professors”).

Regression in Developmental Milestones

About 25% of children later diagnosed as having ASD may develop some language that they suddenly or gradually stop using between the ages of 15 months and 24 months. They might also become more socially withdrawn. This change is called a regression in skills. Some families will recall subtle differences that might have been present before the regression, such as their child not turning when his name was called.

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