Please allow me to clarify my understanding. According to previous posts, the effect of "adjust" is to remove the influence of the null-space effects from the data (e.g the effects of motion and constant term). These null-space effects are supposed to be identical across conditions, which can be represented by an F-contrast consisting of "eye(3)" in the contrast manager if my model has 3 conditions of interest. By "adjust," we can regress out these null-space effects, and that is why we have to adjust for an F-contrast during "eigenvariate" extraction of time series. Otherwise, the time series will be in U-shape). Am I correct?