The epoching of the EEG data was performed with BrainVision Analyzer 2.0 (Brain Products GmbH). For each of the 300 trials presented to each participant, a 1 s epoch was extracted from 405 ms pre-stimulus to 595 ms post-stimulus. Further processing was performed using the Independent Components Analysis (ICA) Toolbox (Makeig et al., 1996) in Matlab (Mathworks, Inc.) and with custom software in IDL (ITT Visual Information Solutions). ICA was used to remove ocular and other artifacts. The single trial epochs for each subject were submitted to ICA, which typically resulted in an IC that accounted for eye blink artifact, and sometimes other ICs that accounted for other artifacts such as muscle artifacts. Artifact ICs were identified based on their characteristic topographies, time courses, and frequency distributions. The activations of the artifact ICs were set to zero and an inverse transformation was performed to return the single trial data to the voltage domain, minus the artifacts. The artifact criteria were: 1) > +/− 90 μV change in one time point; 2) amplitude range within an epoch exceeding 200 μV; and
