ERP waveforms elicited at left, midline, and right frontal electrodes (F3, Fz, and F4 of the 10–20 system), and at left, midline, and right parietal electrodes (P3, Pz, and P4) by correctly recognized studied words (hits) and correctly classified new words (correct rejections). (a) In the two controls, averaged together. (b) In Jon. (c) ERP waveforms of the differences between hits and correct rejections for the controls (dotted lines) and Jon (solid lines) including midline (Fz, Cz, Pz) and central (C3 and C4) electrodes.