An evaluation of PLI values in the rats using MANOVA revealed a main effect of tone (frequent vs. infrequent: F=160.7, df=1,124, p<0.001) and a main effect of electrode location (F=25.9, df=1,124, p<0.001). The infrequent tone had a significantly higher PLI value (0.54 ± 0.01) than the frequent tone (0.34 ± 0.01). Grand means revealed that frontal cortex had significantly higher PLI values (0.48 ± 0.01) than parietal cortex (0.4 ± 0.01). Exploratory repeated measures ANOVA revealed that periadolescent rats had significantly higher PLI levels than adult rats to the infrequent tone in the delta (F=19.3, df=1,32, p<0.001) frequencies in FCTX and lower PLI values in the alpha (F=8.7, df=1,32, p= 0.006) frequencies in PCTX, data presented in Figure 4b and Table 4. Grand averages of the PLI values for periadolescent and adult rats are presented in Figure 8.
