Relationships between ERP abnormalities and psychometric performance in AD/HD

Proposal details

Title: Relationships between ERP abnormalities and psychometric performance in AD/HD
Research Area(s): ADHD and Allied Conditions
Background: A number of abnormalities in ERP components following WM non-target/update (soon to be submitted), WM target and distractor (published 2006) stimuli have been identified in children diagnosed with AD/HD, with the extent and nature of these abnormalities varying with age and subtype. How these abnormalities relate to psychometric performance is unknown. The current study aims to assess how these previously identified ERP abnormalities relate to psychometric performance relative to age and AD/HD subtype.
Aims: It is predicted that AD/HD groups (children and adolescents diagnosed with the Predominantly Inattentive and Combined subtypes of AD/HD) will display significantly poorer performance than controls on a number of psychometric paradigms. Furthermore, that previously identified ERP abnormalities will relate to poor performance, and that these relationships will reflect underlying cognitive processes common to both the ERP component and task. For instance, it is predicted that AD/HD groups that displayed attenuated N300 amplitude, which reflects the retrieval of relevant prior information for ongoing operations, will display poorer performance on tasks requiring them to remember previous events/stimuli such as the auditory verbal learning task (AVLT) and that N300 amplitude and performance on the AVLT will be related.
Method: Psychometric data from those diagnosed with AD/HD will firstly be compared to controls to investigate how performance varies between the groups. Secondly, performance measures found to be abnormal within AD/HD groups will be correlated with previously identified ERP abnormalities to investigate the relationships between ERPs and performance. These correlations will also be compared with correlations in controls using the same variables, so to investigate whether the relationships are significantly different from each other (Cohen & Cohen, 1983).