At lateral centrotemporal sites (T7/8, C3/4, FC5/6, CP5/6) for factor 305, there was a highly significant main effect of intensity, F(1,63) = 131.7, p < .0001, confirming the presence of theN1 sink for high but not low odor intensities (Figure 3B, top; for detailed ANOVA means, see supplementary Table A1). A significant Group × Intensity interaction, F(1,63) = 6.11, p = .02, resulted froma reduction of N1 sink amplitude in schizophrenia for high- but not low-intensity stimuli: simple group main effects at high intensity, F(1,63) = 5.87, p = .02, at low intensity, F(1,63) < 1.0, n.s. There were also a significant interactions of Group × Gender, F(1,63) = 4.15, p =.05, and of Group × Gender × Intensity, F(1,63) = 4.87, p =.03, which originated from greater high intensity N1 sinks for healthy women compared to healthy men (M ± SD, −1.42 ± 1.57 vs. −0.97 ± 0.92), with patients showing the opposite gender effect (−0.51 ± 0.95 vs. −0.95 ± 1.02); simple Group × Gender interaction effects, at high intensity, F(1,63) = 5.27, p =.03, at low intensity, F(1,63) < 1.0, n.s.
