Effects of NRG3 rs10748842 on prefrontal cortex physiology during working memory performance. A, Significantly greater activation of the VLPFC during working memory performance in healthy volunteers carrying one or two C alleles compared with T/T homozygotes during 2-back performance relative to 0-back performance (Z = 4.7; p = 0.008, whole-brain FWE corrected). B, Significant group by NRG3 genotype interaction effects on DLPFC activation during working memory performance (Z = 4.6; p = 0.016, whole-brain FWE corrected). The bars represent means across subjects, and the error bars represent SEM. C, The activation map of the group by genotype interaction analysis is overlaid on sagittal and coronal sections of a structural template image (p = 0.001, uncorrected, for presentation purposes). The color bar represents t values. Notably, the unstandardized effect sizes in A and B are at the order of 0.1% whole-brain mean changes in BOLD signal, indicating that the large sample size did not sensitize our analyses to trivial effect sizes.