A) Representative GABA/glycine-mediated PSCs (average of 10 traces) recorded in the presence of CNQX (5 µM). B) Glutamate-mediated PSCs (average of 10 traces) recorded in the presence of picrotoxin (50 µM), strychnine (10 µM), and cyclothiazide (100 µM). All recordings, in response to 100 Hz electrical stimulation in the MNTB, at a holding potential of −70 mV, with an external Ca++ concentration of 2 mM. C–E) Summary of PPRs at inter-pulse intervals of 10, 20, 50, and 100 ms for the GABA/gly component in (C) 0.1 mM (D) 2.0 mM, and (E) 4.0 mM external Ca++. * P<0.05 (Kruskal-Wallis test; Dunn's post hoc). F–H) Summary of PPRs for glutamate component at 10, 20, 50, and 100 ms inter-pulse intervals in (F) 0.1 mM, (G) 2.0 mM, and (H) 4.0 mM external Ca++. Open symbols in C–E indicate which groups showed significant differences.