Neurocognitive and behavioral characteristics of ADHD with cognitive disengagement syndrome and specific learning disorder

Abstract

This study examined how comorbid Cognitive Disengagement Syndrome (CDS) and Specific Learning Disorder (SLD) shape neurocognitive and behavioral profiles of children with ADHD. The sample included 844 children aged 6-16, categorized into ADHD-only, ADHD+CDS, ADHD+SLD, and ADHD+SLD+CDS. Cognitive performance was assessed with the WISC-R, and behavioral symptoms with the Teacher Report Form. Group differences were analyzed using ANCOVA, adjusting for age, inattention, and internalizing symptoms. Children with CDS showed higher inattention, internalizing symptoms, and obsessive-compulsive traits than those without CDS. By contrast, SLD was linked to lower oppositional and aggressive behaviors. SLD groups performed worse on WISC-R verbal subtests. Compared with CDS, SLD showed lower Arithmetic and Vocabulary scores, underscoring SLD-related verbal and working memory impairment. After adjustment, CDS did not exhibit distinct cognitive profile. Boys with CDS scored lower on the Information subtest than boys with ADHD-only. Performance IQ and non-verbal subtests did not differ across groups. The overlap of CDS and SLD raises concerns about misattributing SLD-related deficits to CDS. Clinically, these findings highlight the need to rule out SLD whenever CDS is observed. Interventions should be tailored, with educational support prioritized in SLD, attention- and emotion-focused strategies in CDS, and integrated approaches when both are present.