In a previous study (Chorlian et al., 2015), developmental trajectories of theta EROs extending from ages 12 to 25 were determined by non-parametric regression (loess) using as covariates sex, family type (control or alcoholic), and the first two principal components from the stratification analysis of the genetic dataset. Following the determination of the trajectories of the ERO values the trajectories of the genotypic associations of the ERO values were determined. The developmental trajectories (time-series) of the association between cholinergic gene variants and theta band EROs are defined by the effect size of the genetic variants in the non-parametric regression model of the theta band EROs, to which genotype (using an additive model) and a genotype × sex interaction, were added as covariates. For this study, the association of theta band EROs at nine scalp locations in two experimental modalities and 21 SNPs at 131 age centers (ages 12 through 25 at 0.1 year intervals) were calculated. This provides effect size matrices of size 36 × 21 for each age center. The methods used to obtain the results are described in
