Associations between the Adult ADHD Self-Report Rating Scale and the Test of Differential Inhibition and Attention

Associations between the Adult ADHD Self-Report Rating Scale (ASRS) and the Test of Differential Inhibition and Attention (TDIA) A. Benton Darling, M.A. Attention-Deficit/Hyperactivity Disorder (ADHD) ranks among the most common mental health disorders in adults (APA, 2013). ADHD assessment is complicated by heterogenous symptoms, gender and age differences in diagnosis, variability in symptom manifestation across the lifespan, and comorbidity with other psychiatric disorders and medical conditions (Asherson, 2016; Willcut, 2012; Williamson & Johnston, 2015). The stop-signal task (SST) identifies ADHD clinical groups in children and adults (Lifffijt et al., 2005), yet it remains unclear whether SST performance reflects general deficits in attention (Alderson et al., 2007) or a selective deficit in motor response inhibition (Aron & Poldrack, 2005). Studies of SST often involve lower cognitive complexity without the additional inhibitory load produced by interference control (Uno et al., 2006). Currently, there is no research on SST with interference control in the adult population. The aim of this study was to assess the diagnostic utility of response inhibition metrics in the adult population on tasks with greater central processing demands. Forty-nine adults completed the Adult ADHD Self-Report Scale – V1.1 Symptoms Checklist and the Test of Differential Inhibition and Attention (TDIA). Results from hierarchical multiple linear regression analyses showed that TDIA metrics associated with motor response inhibition significantly predicted self-reported symptoms of inattention, hyperactivity-impulsivity, and combined ADHD, over and above metrics representing general attention. This study supports the clinical utility of SST with interference control in identifying ADHD in adults. Furthermore, the results support a conceptual model of ADHD wherein response control deficits are primary to the executive dysfunction associated with the disorder. Possible explanations for these results, limitations of the study, and future directions are explored. ASSOCIATIONS BETWEEN THE ASRS AND TDIA iii ACKNOWLEDGEMENTS I would like to acknowledge the members of my dissertation committee for their guidance and encouragement during this process. Without you, this study would not have succeeded. To my clinical supervisors, especially Dr. Daniel Long and Dr. Narayan Gold, thank you for your support and inspiration. I am forever grateful for your mentorship. To West Virginia University’s College of Education and Human Services, thank you for believing in me and providing me with the opportunity to pursue my dream. To the Carruth Center, with your support I discovered my passion as a psychologist. I will forever cherish the memories of our time together. I would also like to thank my cohort – Adri, Chelsea, Connor, Tim, and Sarah – whose friendship made these past five years one of the greatest joys of my lifetime. You are special people whom I am lucky to consider colleagues and dear friends. May these Country Roads always take us home, to the place where we belong. Finally, I would like to express my love and gratitude to my family, whose unwavering support over the years made this possible. I dedicate my work to you for all that you have contributed to this occasion. To Alex and my new family, the Kinders, you are a blessing. I am excited for the future we will share together. I love and thank you all for the joy you bring to my life. ASSOCIATIONS BETWEEN THE ASRS AND TDIA iv TABLE OF CONTENTS CHAPTER 1: INTRODUCTION AND REVIEW OF SELECTED LITERATURE . 1 Review of Selected Literature . 4 Prevalence . 4 Subtypes and Symptoms . 4 Gender Differences . 5 Age Differences . 6 Etiology and Risk Factors . 7 Pathophysiology . 8 The Attentional System . 10 History of the Taxon . 12 Diagnostic Criteria . 15 ADHD in Adolescence and Adulthood . 16 Persistence . 16 Onset. 18 Course. 19 Comorbidity and Deleterious Outcomes. 20 Assessment and Diagnosis of Adult ADHD . 23 Self-Report. 24 Feigning Symptoms for Secondary Gain . 27 Continuous Performance Tests. 29 Clinical Utility. 31 Go/No-Go Methodology. 33 Interference Control. 34 Stop Signal Paradigm. 35 The Present Study . 43 Research Questions . 43 Hypotheses . 44 CHAPTER 2: METHODS . 46 Research Design . 46 Participants . 47 Sampling Procedures . 47 Measures . 50 World Health Organization Adult ADHD Self-Report Scale – V1.1 Symptoms Checklist (ASRS-V1.1) . 50 Test of Differential Inhibition and Attention (TDIA) . 52 Demographics Questionnaire . 54 Procedures . 54 CHAPTER 3: RESULTS . 58 Descriptive Statistics . 58 Assumptions and Reliability of the Measures . 59 Hypothesis Testing . 61 Hypothesis 1. 61 Hypothesis 2. 62 Hypothesis 3. 63 ASSOCIATIONS BETWEEN THE ASRS AND TDIA v CHAPTER 4: DISCUSSION . 65 Summary of Findings . 65 Limitations . 70 Implications . 72 Future Directions . 76 Conclusion .