Evaluation of neurocognitive characteristics in children diagnosed with attention deficit hyperactivity disorder

This study aimed to examine different components of executive functions in children aged 6–12 years diagnosed with Attention Deficit Hyperactivity Disorder (ADHD) and to compare medicated and unmedicated groups in terms of neurocognitive performance, symptom severity, sleep habits, and parental psychological well-being. A total of 80 children, including 40 receiving methylphenidate and 40 not receiving medication, participated in the study. Neurocognitive functions were assessed using the Cambridge Neuropsychological Test Automated Battery (CANTAB); symptom severity was evaluated with the Conners' Parent Rating Scale–Revised Short (CPRS-RS), sleep habits with the Children's Sleep Habits Questionnaire (CSHQ), and parental mental health with the Depression Anxiety Stress Scale-21 (DASS-21). Children not receiving medication showed significantly higher inattention scores. Clinically significant sleep problems were observed in both groups, indicating that sleep disturbances may occur independently of treatment. Parental psychological distress scores were positively correlated with the severity of children's symptoms. According to CANTAB findings, medicated children made fewer errors on the Stop Signal Task and showed higher target sensitivity and response stability on the Rapid Visual Information Processing test, whereas no difference was found in Spatial Working Memory performance between the groups. Methylphenidate treatment appeared to improve sustained attention and inhibitory control, while its effect on working memory was limited. Given the presence of sleep disturbances and parental psychological distress in both groups, these factors should be routinely assessed in all ADHD cases. In addition to pharmacological approaches, addressing sleep regulation and providing family-based interventions are essential components of a comprehensive treatment plan for ADHD. Key Words: ADHD, executive functions, methylphenidate, sleep, parental stress