“He Was Talking and Then He Just Stopped”: A Look at Regression in Autism

By Lauren Lowry
Hanen Certified SLP and Clinical Staff Writer

Regression refers to losing a skill that a child once had. For example, a child may learn a few words but then stop using them. Or he may lose interest in looking at people even though he often used to look at them. Losing skills during early childhood is one of the red flags for autism spectrum disorder (ASD).

Even though regression has been described in children with ASD for many decades, it continues to be something of a mystery and the information about it is confusing. Recently, researchers have found new ways to learn about regression. They have been studying the younger siblings of children with ASD as these children are at higher risk for developing ASD themselves. By watching these high-risk babies develop, researchers have learned some new things about the earliest signs of regression in young children with ASD. Here are some of their latest discoveries:

Regression may affect early social communication skills more often than it affects language

While most parent descriptions of regression involve children losing words, a recent study found that children with ASD may lose early social communication skills more often than they lose words [1]. Some of these social communication skills include being able to [2]:

  • look at the parent while playing to see if the parent is watching
  • show emotions
  • smile or laugh while looking at the parent
  • follow the parent’s pointed finger to a toy across the room

Researchers hope that by identifying these kinds of early signs of ASD, more children can be identified earlier and provided with the treatment they need [1, 3].

Regression happens early

Most reports of regression describe children losing skills between 18 – 24 months of age [4]. However, new research has found that some children with ASD show differences in their early social communication skills starting around 12 months [3]. These early skills are more subtle than later-developing skills like using words, so when children stop using these early developing skills it can go unnoticed [5]. This could be why many people don’t notice regression in their child until they are toddlers.

More children may experience regression than originally thought

Possibly 80% of children with ASD experience some sort of skill loss.

Past research has estimated that approximately one third of children with ASD experience regression [6]. This information was based on parents’ reports of their child’s development. However, newer studies that have followed children from early infancy have enabled researchers to look for those early, subtle social communication skills during the time when they are expected to develop. These studies have shown that many more children with ASD – possibly over 80% of them – experience some sort of skill loss [3].

It’s not just children with ASD who can lose skills

A recent study compared the development of three groups of babies – children who were typically developing, children who later developed language impairment, and children who later received a diagnosis of ASD [1]. They watched how the babies developed until they were seven years old. They noticed regression in a portion of all three groups of children. The children with ASD lost more skills than the other two groups, but even 26% of typically developing children lost some skills. This makes diagnosis a challenge. Regression is currently seen as a red flag for ASD; however, it is also possible in other groups of children. Researchers hope that by continuing to study the first signs of ASD and noticing any changes in the early skills of infants and toddlers, we might achieve earlier diagnosis and treatment. They suggest that helping children as early as possible may interrupt the development of ASD or change how it progresses [3]. We know that helping children early gives them the best possible start.

If you are concerned about your child’s development or notice that he or she has lost some skills, talk to your child’s doctor or a speech-language pathologist. You can learn more about the early signs of ASD here.


  1. Brignell, A., Williams, K., Prior, M., Donath, S., Reilly, S., Bavin, E. L., Eadie, P. & Morgan, A. T. (2017). Parent-reported patterns of loss and gain in communication in 1- to 2-year-old children are not unique to autism spectrum disorder. Autism, 21(3), 344–356.
  2. Wetherby, A. M. & Prizant, B. M. (2002). Communication and Symbolic Behavior Scales Developmental Profile. Baltimore, MD: Paul H. Brookes Publishing Co., Inc.
  3. Ozonoff, S. & Iosif, A. (2019). Changing conceptualizations of regression: What prospective studies reveal about the onset of autism spectrum disorder. Neuroscience and Biobehavioral Reviews, 100, 296-304.
  4. Thurm, A., Powell, E. M., Neul, J. L., Wagner, A., & Zwaigenbaum, L. (2018). Loss of skills and onset patterns in neurodevelopmental disorders: Understanding the neurobiological mechanisms. Autism Research, 11(2), 212-222.
  5. Bradley, C. C., Boan, A. D., Cohen, A. P., Charles, J. M., & Carpenter, L. A. (2016). Reported history of developmental regression and restricted, repetitive behaviors in children with autism spectrum disorders. Journal of developmental and behavioral pediatrics, 37(6), 451-456.
  6. Barger, B. D., Campbell, J. M., & McDonough, J. D. (2013). Prevalence and onset of regression within autism spectrum disorders: A meta-analytic review. Journal of Autism and Developmental Disorders, 43(4), 817-28.