Chunk #148 — 10.0 Where Do We Go From Here? — 10.4 More research on the utility of an endophenotype — 10.4.2 Enhancing our understanding of brain mechanisms
target-distractor incompatibility was parametrically varied in order to probe the sensitivity of the N2 ERP component to the degree of response conflict subjects experience when presented with a particular variant of the stimulus array (Forster, Carter, Cohen, & Cho, 2011). The nogo-N2 is considered a candidate endophenotype for alcoholism (Kamarajan & Porjesz, 2015), and similar types of experimental manipulations are likely to inform us about the nature of individual differences in this putative endophenotype. Lenartowicz and colleagues (Lenartowicz et al., 2014) used a visual-spatial version of the Sternberg working memory test in a sample of children with ADHD and typically developing controls to parametrically vary task load and thereby try to isolate the source of the difficulties experienced by children with ADHD. Studies such as these can help to isolate the psychological and neural processes reflected in putative endophenotypes for ADHD such as the P2 ERP component and thus the precise nature of genetic risk reflected in the endophenotype. Testing for associations with genetic variants is not a necessary part of this type of research. However, studies that provide a better characterization of the mechanisms underlying a putative endophenotype and the latent genetic risk it reflects will also ultimately be
