function, and finally to behavior (de Geus, 2010; Iacono, 2018). Investigating these pathways will be greatly aided by increase sample sizes and by establishing the EEG features' polygenicity (Holland et al., 2019), as well as variant‐level joint‐polygenicity analyses that are currently being developed (Frei et al., 2019) to investigate the nature of overlap between traits (in our case, EEG features and psychiatric/neurological genetic overlap).