(A-D) Characteristics of miniature excitatory postsynaptic currents (EPSCs) recorded from hippocampal CA1 pyramidal neurons of wild-type (A, B) and Ctsd−/− mice (C, D) at postnatal day (P) 16-17. Asterisks in example recordings (A, C) indicate regions presented with the expanded time scale (B, D). (E) Cumulative distribution and averaged values of mEPSC inter-event interval, * p < 0.05. (F) The cumulative distribution and averaged values of mEPSC amplitude.