(**a**) A representative coronal brain section from the *SOM-IRES-Cre/Ai14* mice stained with anti-GAD67 antibody (left). The SOM^{+} neurons expressed both tdTomato (middle) and GAD67 (see overlay in right). Inset: a portion of CeL shown in higher magnification. The borders of CeL, CeM, LA, and BLA are outlined. (**b**) A schematic recording configuration. In red is a SOM^{+} neuron. (**c**) Left: representative EPSC traces recorded from SOM^{−}/SOM^{+} neuronal pairs in CeL of the following groups: control (control group, upper panel), “fear, 3 h” (3 hrs following fear conditioning, middle panel), and “fear, 24 h” (24 hrs following fear conditioning, lower panel). Calibrations: 50 pA and 20 ms. Middle: quantification of AMPAR-mediated EPSC amplitude, which was normalized to the mean EPSC amplitude of SOM^{−} neurons. SOM^{+} neurons had smaller AMPAR-mediated EPSC than SOM^{−} neurons in control animals, but this relationship was reversed in fear-conditioned animals (control: SOM^{−}, 1 ± 0.23, SOM^{+}, 0.59 ± 0.12, n =13 pairs, 4 animals, t = 2.53, DF = 12, **P* < 0.05, paired *t*-test; fear, 3 h: SOM^{−}, 1 ± 0.16, SOM^{+}, 2.07 ± 0.40, n = 11 pairs, 3 animals, t = −3.42, DF = 10, ***P*<0.01, paired *t*-test; fear, 24 h: SOM^{−}, 1±0.34, SOM^{+}, 2.49±0.37, n = 8 pairs, 2 animals, t = −2.94, DF = 7, **P* < 0.05, paired *t*-test; #*P* < 0.05, *F*_{(2,29)} = 11.7, one-way analysis of variance (ANOVA) followed by Tukey’s test). Right: quantification of NMDAR-mediated EPSC. SOM^{+} neurons had smaller NMDAR-mediated EPSC than SOM^{−} neurons in control animals, but this difference disappeared in fear-conditioned animals (control: SOM^{−}, 1 ± 0.31, SOM^{+}, 0.63 ± 0.20, n = 13 pairs, 4 animals, t = 2.75, DF = 12, **P* < 0.05, paired *t*-test; fear, 3 h: SOM^{−}, 1± 0.11, SOM^{+}, 1.3 ± 0.29, n = 11 pairs, 3 animals, t = −1.14, DF = 10, *P* > 0.05, paired *t*-test; fear, 24 h: SOM^{−}, 1 ± 0.16, SOM^{+}, 1.13 ± 0.26, n = 7 pairs, 2 animals, t = −0.40, DF = 6, *P* > 0.05, paired *t*-test; n.s., non-significant). (**d**) Representative mEPSC traces recorded from SOM^{+} (red) and SOM^{−}(black) neurons in the CeL of different groups. Calibrations: 20 pA and 500 ms. (**e**) Upper panel: fear conditioning increased the mEPSC frequency of SOM^{+} neurons (SOM^{+}, control: 1.73 ± 0.27 Hz, n = 15 cells, 3 animals; fear, 3 h: 3.58 ± 0.59 Hz, n = 15 cells, 3 animals; fear, 24 h: 3.64 ± 0.53 Hz, n = 12 cells, 3 animals; **P* < 0.05, ***P* < 0.01, ****P* < 0.001, bootstrap with Bonferroni correction), while decreased that of SOM^{−} neurons (SOM^{−}, control: 3.26 ± 1.02 Hz, n = 12 cells, 3 animals; fear, 3 h: 1.11 ± 0.14 Hz; n = 10 cells, 3 animals; fear, 24 h: 1.42 ± 0.16 Hz, n = 13 cells, 3 animals; **P <* 0.05, ****P <* 0.001, bootstrap with Bonferroni correction). Lower panel: fear conditioning increased the mEPSC amplitude of SOM^{+} neurons at 3 hrs after fear conditioning (SOM^{+}, control: 13.03 ± 0.60 pA, n = 15 cells, 3 animals; fear, 3 h: 16.26 ± 1.21 pA, n = 15 cells, 3 animals; fear, 24 h: 14.28 ± 0.63 Hz, n = 12 cells, 3 animals; **P* < 0.05, bootstrap with Bonferroni correction), but did not affect that of SOM^{−} neurons (SOM^{−}, control: 12.85 ± 0.64 pA, n = 12 cells, 3 animals; fear, 3 h: 11.74 ± 0.44 pA, n = 10 cells, 3 animals; fear, 24 h: 12.06 ± 0.61 Hz, n = 13 cells, 3 animals; *P* > 0.05, bootstrap). Fear, fear-conditioned. Error bars, s.e.m.

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