Cognitive Deficits in Children with Attention Deficit Hyperactivity Disorder: A Long-Term Follow-Up.

Abstract The phrase long-term follow-up in the title of this paper refers to my Presidential Address to CPA (Douglas, 1972), in which I made my first attempt to pull together my on the nature of the cognitive deficits associated with Childhood Hyperactivity, now known as Attention Deficit Hyperactivity Disorder. This paper represents a much later attempt to my thinking. The paper describes my current conceptualization of the cognitive and motor deficits of children with ADHD. It points to the self-regulatory nature of their deficits, and stresses the importance of differentiating between the attentional and inhibitory components, as opposed to the strategic or organizational components, of self-regulation. A main theme is the need for better collaboration among investigators to develop a diagnostic profile of operationally defined, laboratory-based measures that can assess specific attentional, inhibitory, and strategic deficits under clearly specified conditions. I argue that the profile should also include measures and manipulations that demonstrate the cognitive strengths of ADHD children, which are frequently masked by impaired self-regulation. I discuss the possibility of using tasks and games based on the operational definitions to try to influence the early development of cognitive and motor control processes in ADHD. I also argue that pervasive, dose-dependent stimulant effects across multiple simple and complex tasks point to action on self-regulatory processes and provide one example showing that high doses can produce overregulation. I am very grateful to have been honoured with the Lifetime Contributions award from the Canadian Psychological Association, and for the invitation to use this occasion to my thinking on the cognitive and motor deficits associated with Attention Deficit Hyperactivity Disorder (ADHD), a topic that has consumed my interest for many years. It is particularly appropriate that this event is taking place at the Annual Meeting of CPA in St. John's, Newfoundland. Some years ago, when I was President of CPA, I gave my Presidential Address at the Annual Meeting, which also was held in St. John's that year. I developed a deep affection for the town, and it is a great pleasure to be back. As you may have guessed, the talk dealt with ADHD, then known as Childhood Hyperactivity. The topic was Stop, Look, and Listen: The Problem of Sustained Attention and Impulse Control in Hyperactive and Normal Children (Douglas, 1972). Thus, you can consider this talk a long-term follow-up. Since that time, the field has experienced a mind-boggling surge of research. Theories and models attempting to establish the basic nature of the disorder have proliferated; the debate about diagnostic and treatment approaches has taken many turns; and neuroscience advances in brain imaging and the neurotransmitters have begun to show an impact. As new evidence and new theories have emerged, those of us working in the field have had to continually update our thinking. I will use this talk to give you a brief overview of my current conceptualization of the cognitive and motor deficits associated with ADHD, highlighting the research that has guided my thinking, and pointing to possible diagnostic and treatment implications. Search for the Core Deficit Attempts to characterize the cognitive deficits of children with ADHD have emphasized several key processes, including attention, inhibition, state regulation, delay aversion, and executive functions. Considerable confusion has developed, however, because investigators have differed in the priority they assign to each of these processes, arid in how they conceptualize the relationships among them. In the model proposed by Barkley (1997), a core inhibitory deficit impairs the development of several executive functions, including working memory. In contrast, Denney and Rapport (2001) proposed a model in which working memory constitutes the key causal process. …