Grand average global field power (GFP) and corresponding topographic representations.

<p><b>A)</b> Grand average GFP. The dotted lines indicate peak latency of the different ERP components. Two different components can be identified: (1) A negative voltage between 100–200 ms, maximal at Cz, labeled as N1; (2) A positive voltage between 240–380 ms, maximal at Cz, labeled as P2. <b>B)</b> Topographic representations of the ERP components at the ERP latencies. To best illustrate the maximal activity in each representation we adjusted the scale to its maximal absolute values (for increases and decreases in voltages). As a result the scale differs between the different representations and is therefore left out.