The Unique Roles of Executive Function in Co-Occurring Psychopathologies in Autism

Children with autism spectrum disorder (ASD) often experience co-occurring psychiatric conditions, such as anxiety and attention-deficit/hyperactivity disorder (ADHD), which significantly impair daily functioning. However, the underlying mechanisms linking these conditions to core ASD features remain poorly understood. This study examined relationships between anxiety, ADHD symptoms, and multi-domain neurocognitive abilities in a clinic-based sample of 701 Chinese children with ASD (mean age 8 years, 13.4% female), using the Hong Kong version of the Penn Computerized Neurocognitive Battery. Initial correlations revealed negative associations between cognitive performance and ADHD symptoms, but no direct links with anxiety. Ordinal regression demonstrated that poorer executive function (EF) independently predicted greater ADHD severity along a continuum from no ADHD to subclinical features to co-occurring ADHD, in a dose-dependent manner, even after controlling for core autism symptoms, other cognitive domains, and full-scale IQ. Moderation analyses showed that stronger EF specifically buffered the associations between sensory hyper-responsiveness/sensory-seeking and anxiety symptoms-an effect not seen with other cognitive domains or full-scale IQ. These findings indicate that EF plays a unique, compensatory role in modulating the two most common co-occurring psychopathologies in ASD. Systematic assessment of EF could support early risk stratification, while EF-targeted interventions may help mitigate the burden of ADHD and anxiety in children with ASD.