M. Cagy, A.F.C. Infantosi, A.I. França and M. Lemle. Statistical analysis of event-related potential elicited by verb-complement merge in Brazilian Portuguese. Braz J Med Biol Res 2006; 39: 1465-1474.
Figure 3. Description of the automatic N400 locating procedure: negative peaks are recognized from the ascendant zero-cross of the first approximate waveform derivative within the 200-600-ms window, which could be done by simply using the sign of the derivative. In case of multiple findings, the most pronounced negative peak is chosen.