Figure 4
Laminar distribution of N2 LFP, current sinks and sources. (a) Changes of N2 field potential gradient amplitude across microelectrode contacts and averaged across trials (within each subject), in 7 patients. (b) In 4 patients with histological reconstruction, there are significant differences in N2 amplitude between cortical layers as revealed by one-way ANOVA (F(5) = 7.7, p < 0.001, η2 = 0.336) and Tukey HSD post-hoc test (tII-IV = 4.3, p < 0.001, tII-V = 5.77, p < 0.001, tII-VI = 4.89, p < 0.001) (black bars). There was no significant difference in N2 – CSD source amplitude (indicated by red bars) between cortical layers. (c) The biphasic distribution of current sinks and sources of CCEPs across cortical layers. Overlay of 6 patients. (d) The N2 current source is maximal in middle cortical layers around layer III. Data is normalised to the peak response in each patient.
