Associations Between Sleep-Related Characteristics and Mind Wandering in Adults with ADHD: A Cross-Sectional Study with a Control Group

Excessive mind wandering is increasingly recognized as a clinically relevant cognitive feature of adult attention-deficit/hyperactivity disorder (ADHD), yet its relationship with sleep-related characteristics remains insufficiently understood. This cross-sectional study with a control group examined associations between sleep-related characteristics and excessive mind wandering in 316 adults with clinically confirmed ADHD and 121 screened controls. Participants completed measures of ADHD symptoms, mind wandering, anxiety–depressive symptoms, and self-reported sleep-related characteristics adapted from Pittsburgh Sleep Quality Index items; mid-sleep time was calculated from reported sleep onset and final awakening. Group comparisons, correlation analyses, and multiple regression analyses were conducted. Adults with ADHD showed higher mind wandering, greater ADHD symptom severity, anxiety–depressive symptom burden, poorer subjective sleep quality, and later mid-sleep time than controls, whereas sleep duration did not differ between groups. Mind wandering was associated with ADHD symptom severity, anxiety–depressive symptoms, later mid-sleep time, and poorer subjective sleep quality. In regression analysis, ADHD diagnosis was the strongest independent correlate of mind wandering. Anxiety–depressive symptom burden, poorer subjective sleep quality, and later mid-sleep time, but not sleep duration, also remained independently associated with higher mind wandering. Findings suggest that sleep timing and subjective sleep quality may be clinically relevant to excessive mind wandering in adults with ADHD.