Delinquency in adolescents with attention deficit hyperactivity disorder and/or reading disability

Abstract

Despite many studies report a high prevalence of attention deficit hyperactivity disorder (ADHD) and reading disability (RD) among young delinquents, it is still not clear how the two disorders connect with delinquency. The main aim of this thesis was to understand the origin and progression of juvenile delinquency in groups of Chinese adolescents with ADHD, RD or comorbidity ADHD+RD. Three studies were conducted and reported in this thesis.In Study 1, executive functions(EF) and severity of delinquency were examined. Participants with ADHD only (n=29), RD only (n=24) and comorbidity ADHD+RD (n=35) were recruited from juvenile institutions in Hong Kong. Typically developing controls (n=29) were recruited from local schools. Assessment batteries on EF and self-reported questionnaire on delinquency were administered. Results of Study 1 showed that participants with ADHD were characterized with impairment in inhibition whereas participants with RD were characterized with impaired processing speed and visual memory. Compared to the pure groups, participants in the comorbid condition exhibited unique deficit in interference control. Importantly, the current study showed that the comorbid group had the highest severity of delinquency, and interference control; theunique deficit exhibited in the comorbid group was found to be a significant predictor of the severity of delinquency. In Study 2, psychosocial characteristics of the same juvenile sample of Study 1 were compared with typically developing control. A psychosocial questionnaire covering domains of academic orientation, parental relationships and victimization was administered. Results of Study 2 suggested that participants with RD wereassociated with negative effect across all psychosocial domains whereas participants with ADHD were mainly associated with poor academic orientation. Moreover, the comorbid group did not report having poorer psychosocial outcomes than the pure groups. The current data suggested that academic orientation was a significant factorpredicting onset of delinquency whereas direct victimization and poor father-child relationships marginally predicted severity of delinquency. In Study 3, the role of decision making at risk-taking events was investigated among the four study groups. Participants with ADHD only (n=37), RD only (n=35), comorbidity ADHD+RD (n=35), and control (n=36) were recruited from normal schools with varying levels of delinquency. A risk-taking simulated task, the Balloon Analogue Risk Task (BART) and a teacher-reported questionnaire on delinquency were administered. Results of Study 3 showed that participants with ADHD, despite their great risk-taking propensity, were motivated by the prospect of immediate feedback. In contrast, participants with RD were found to display normal risk-taking propensity, yet were less sensitive to punishment, suggesting a failure to switch between approach and avoidance behaviours for risky situations. Importantly, the comorbid group had the highest teacher-reported delinquency score, and exhibited the greatest risk taking and least sensitivity to punishment which further supported that comorbid condition might have a stronger impact on risk taking or even delinquency than pure groups. The present study increased knowledge about the unique delinquency pathways and important correlates associated with ADHD, RD and their comorbidity. The practical implications for intervention measures and early identification of at-risk adolescents with ADHD, RD and comorbidity were discussed.