N170 Latency

A two-way ANOVA was performed on the N170 peaklatency measured between 140 and 200 msec at T5 andT6 (where the N170 was most conspicuous), with Stimu-lus Category (orthographic, nonorthographic) and Hemi-sphere (left, right) as within-subject factors. This analysisshowed that the N170 latency was similar for ortho-graphic and nonorthographic categories (F(1, 23) <1.00) and significantly shorter at T5 (168 msec) than atT6 (175 msec) (F(1, 23) = 5.96, p□< 0.025). The interac-tion between Stimulus Category and Hemisphere was not significant (F(1, 23) = 0.05).

Figure 2. Scalp distribution of the negative potentials elic-ited in each task. Pink-purple hues represent negative volt-ages, yellow-green hues represent positive voltages.(A) Back view of the scalp potential (first row) and currentdensity (second row) distributions of the N170s to ortho-graphic (left) and nonorthographic (right) stimuli in the sizetask. (B) Lateral view of the N170s scalp potential distribu-tions to orthographic and nonorthographic stimuli in the sizetask. (C) Scalp potential distributions of the N320s to pro-nounceable and nonpronounceable stimuli in the rhyme task.(D) Scalp potential distributions of the N350s to phonologi-cal legal and phonological illegal stimuli in the lexical deci-sion task. (E) Scalp potential distributions of the N450s topseudowords and words stimuli in the semantic decision task.