Changes in Autism Trait Severity Have Varied Mental Health Effects

Changes in Autism Trait Severity

Researchers from UC Davis Health cast new light on the correlation between autism traits and middle childhood mental health through a long-term study. The research paper establishes a correlation between alterations in fundamental autism traits and the occurrence of comorbid mental health issues among elementary school-aged children.

“Our findings suggest that different aspects of a child’s development may affect each other over time,”

said lead author Einat Waizbard-Bartov, a doctoral researcher in developmental psychology at the UC Davis MIND Institute

Autism traits and mental health challenges are likely to interact throughout development.

A key finding was that a reduction in restrictive and repetitive behaviors during elementary school was linked to the emergence of mental health challenges, lending support to the idea that these behaviors may benefit autistic individuals. An increase in social-communication difficulties during this time was also linked to anxiety and other mental health challenges.

Tracking Changes in Characteristics

Previous research by Waizbard-Bartov has shown that autism characteristics can change significantly between the ages of 3 and 11.

The current study included 75 autistic children ages 6 to 11, including 15 girls. All were part of the MIND Institute’s Autism Phenome Project, a large, long-term study aimed at identifying different subtypes of autism.

The research team assessed the children’s mental health symptoms and restricted and repetitive behaviors, which can include seeking sensory stimulation, hand-flapping, or sticking to set routines, using parental interviews and questionnaires.

They tracked changes in autism characteristics using the Autism Diagnostic Observation Schedule Calibrated Severity Score.

Restricted and Repetitive Behaviors

About a fifth (21%) of the youth had more severe social-communication difficulties, as well as an increase in anxiety, ADHD and behavioral challenges. In contrast, nearly 23% had decreased restricted and repetitive behaviors but higher anxiety levels by age 11. Nearly all — 94% — met the criteria for an anxiety disorder.

Approximately one-third of the participants had both decreasing restricted and repetitive behaviors as well as increased social-communication difficulties.

“We were pleased to see that our results confirmed what has been suspected by other autism researchers and clinicians as well as autistic individuals, that some forms of restricted and repetitive behaviors can potentially help to self-soothe,”

said senior author David Amaral, distinguished professor in the Department of Psychiatry and Behavioral Sciences, MIND Institute.

Waizbard-Bartov notes that the findings question the wisdom of therapies that try to eliminate these behaviors.

Mental Health Challenges

Given this finding, it is possible that attempting to eliminate repetitive behaviors without providing alternative self-soothing tools is not the best intervention strategy.

The study is the first, to the authors’ knowledge, to demonstrate an association between mental health challenges and increases in the severity of social-communication difficulties for autistic children.

This happened in children who had typical cognitive functioning and showed decreases in core autism traits during early childhood.

“We don’t currently understand why this happened. One possibility is that due to their relatively high cognitive ability, they became aware of their social challenges, and this may have contributed to increasing anxiety. It’s definitely an area where we need more research,”

Amaral said.


Many autistic children experience changes in core symptom severity across middle childhood, when co-occurring mental health conditions emerge. We evaluated this relationship in 75 autistic children from 6 to 11 years old. Autism symptom severity change was evaluated for total autism symptoms using the autism diagnostic observation schedule calibrated severity score, as well as social-communication symptoms calibrated severity score, and restricted/repetitive behaviors calibrated severity score. Children were grouped based on their symptom severity change patterns. Mental health symptoms (attention-deficit hyperactivity disorder, anxiety, disruptive behavior problems) were assessed via parental interview and questionnaire and compared across the groups. Co-occurring mental health symptoms were more strongly associated with change in social-communication symptom or restricted/repetitive behavior severity than with total autism symptom severity. Two relevant groups were identified. The social-communication symptom-increasing-severity-group (21.3%) had elevated and increasing levels of anxiety, attention-deficit hyperactivity disorder, and disruptive behavior problems compared with children with stable social-communication symptom severity. The restricted/repetitive behavior-decreasing-severity-group (22.7%) had elevated and increasing levels of anxiety; 94% of these children met criteria for an anxiety disorder. Autism symptom severity change during middle childhood is associated with co-occurring mental health symptoms. Children that increase in social-communication symptom severity are also likely to demonstrate greater psychopathology, while decreases in restricted/repetitive behavior severity are associated with higher levels of anxiety.

  1. Waizbard-Bartov, E., Ferrer, E., Heath, B., Andrews, D. S., Rogers, S., Kerns, C. M., Wu Nordahl, C., Solomon, M., & Amaral, D. G. (2023). Changes in the severity of autism symptom domains are related to mental health challenges during middle childhood. Autism, doi: 10.1177/13623613231195108