Temporal N1 (150 ms) is clearly distinguished from N1 by the progression and spread of the pre-Sylvian CSD sink onto the convexity of the temporal lobe. At the temporal N1 peak, this sink obliterates the earlier post-Sylvian source, and a vertex source forms and reaches a maximum at the peak of P2. However, the temporal N1 component is prominent only for the CSD waveform over the convexity of the temporal lobe (see CSD waveform at site T8 in Fig. 4A), where the ERPs show a (reference-dependent) low-amplitude peak of variable latency. Despite this volatility, ERP evidence for this component takes the form of a topographic shift of the residual N1 across the temporal lobe that is quite consistent with the CSD (Fig. 4B, second row), and that disappears by the time of the midline positive peak (CSD source) corresponding to P2 (185 ms).
