An often employed paradigm that reliably generates both P3a and P3b is the so-called novelty oddball paradigm (e.g., Fabiani and Friedman, 1995), a modified 3-stimulus version of a classic 2-stimulus target detection task. Participants are instructed to respond to infrequent tones (targets, 10% probability) embedded in a series of frequent tones of different pitch (nontargets, 80%) as well as infrequent stimuli consisting of unique environmental sounds (novels, 10%), which are to be ignored. In this paradigm, a P3b is mostly observed for targets, whereas a P3a is primarily seen for novels (and hence also called novelty P3). Figure 11 shows target and novel ERPs at midline sites Cz and Pz, which were recorded from 49 healthy adults during this novelty oddball task (for details, see Tenke et al., 2010). As noted above, P3b amplitudes and latencies at Pz for targets varied markedly between EEG references, showing larger and earlier peaks for ERPs referenced to linked mastoids or nose (peak latencies 340 ms and 350 ms) compared to the common average (370 ms; Fig. 11A), notwithstanding the fact that their window-based
