Children with autism and attention deficit hyperactivity disorder. Relationships between symptoms and executive function, theory of mind, and behavioral problems.

Berenguer et al. (2018) compared three groups of late-elementary kids: ASD only, ADHD only, and ASD plus ADHD. They gave each child tests of executive function, theory-of-mind, and behavior checklists.

Parents and teachers also filled out rating scales. The goal was to see if the double-diagnosis group had extra struggles beyond the single-diagnosis groups.

The ASD+ADHD kids scored worse on working-memory and planning tasks than either single-diagnosis group. They also made more errors on false-belief tests, a quick measure of theory-of-mind.

Inattention scores, not hyperactivity, best predicted these EF and ToM gaps. ASD symptom scores, in turn, predicted wider behavior problems like irritability and social withdrawal.

Tonizzi et al. (2022) pooled many studies and found the same pattern: kids with ASD plus ADHD traits show sharper executive-control and adaptive-skill deficits than kids with ASD alone. Their meta-analysis actually includes the 2018 data, so the two papers reinforce each other.

Neely et al. (2016) saw similar EF links in younger kids aged 6-8, hinting that the double-hit profile starts early. Carmen’s team extended the picture upward to 8-11-year-olds and added theory-of-mind data.

At first glance Keintz et al. (2011) seems to disagree: they reported that inhibitory control tied only to ADHD impulsivity, not to ASD social deficits. The key difference is focus. S et al. looked at which cognitive skill predicts which symptom, while Carmen et al. asked whether having both diagnoses worsens overall EF and ToM. Both can be true: separate links exist, and the combined group still ends up with bigger deficits.

If you have a client diagnosed with both ASD and ADHD, do not assume the treatment plan can simply sum two protocols. Target core executive skills like working memory and cognitive flexibility alongside social-cognition training. Track inattention separately from hyperactivity; it is the attention piece that most covaries with EF and ToM shortfalls. Finally, share the double-hit concept with parents so they understand why extra supports at school and home may be needed.