Quantification of the impact of hearing on microglial parameters in the DG and CA3 by post hoc pairwise comparisons between groups as a function of age. The values are presented as the mean ± SEM of 5-8 mice per group. *P<0.05, **P<0.01 and ***P<0.001 in post hoc comparisons between age-matched groups after two-way ANOVA, showing a significant effect of NIHL.