(A) Shows representative traces (left; middle, NOTE time scale change) with ensemble averages (right) from 8 MS/DB neurons ranging in age from 4 days to 24 months. (B) Percent of all neurons recorded with GABAAR mPSCs in MS/DB slices on PD 4–9 (n=12–24 cells across groups); differences vs PD 4; ANOVA, **P <0.01, ***<0.001). (C–F) GABAAR mPSC parameters are grouped by age-related intervals for amplitude (C), frequency (D), and ensemble average bi-exponential time constant τ1 (E), and τ2(F) (n=9–137 cells across all groups; values represent Mean ± S.E.M; comparison based on difference vs PD 4–9 group; ANOVA, ***P <0.001).