It has been reported that the intrinsic excitability of CA1 PNs is altered in FXS mice.[29] Our current‐clamp recordings indicated that PNs from Fmr1‐KO+MGE mice exhibited reduced excitability compared to those from Fmr1‐KO mice (Figure 3L,M). The gene discussed is FMR1; the disease is fragile X syndrome.