The phase-locking factor and total power values that were entered into the statistical analysis were extracted for each frequency of interest (δ = 3 Hz; θ = 4–7 Hz) over a 50 ms window centered on each individual subject’s P3 peak latency. However, it is important to note the varying temporal window of the wavelet approach. Specifically, time–frequency data extracted 50 ms surrounding the P3 peak result from convolution with a wavelet that spans 6σ t milliseconds of EEG data for each sample in the 50 ms extraction window. For example, 5 Hz activity for a subject with a P3 peak latency of 300 ms is estimated using data points that end at 325 + 3σ t ms (∼925 ms at the 5 Hz frequency). These points are weighted by a Gaussian window centered on the sample of interest (300 ms in this case), but in every frequency, data sampled outside the 50 ms extraction window contribute to the calculation. This P3-locked, 50 ms extraction window was used to best emphasize the time–frequency dynamics at the moment of the ERP peak.
