were submitted to a covariance matrix PCA implemented in Matlab (Kayser and Tenke, 2003). All components were retained and subjected to a varimax rotation, yielding orthogonal factors corresponding to major TF components. To produce interpretable TF factor loadings, 1-D factor loadings were rearranged back into the original order of the 2-D TF measures, and individual subject and electrode factor scores corresponding to the transient GBR component were saved for subsequent analyses.
