Altered synaptic transmission and plasticity in the perirhinal cortex of Crtl1 ko mice. A, Setup for extracellular field recordings from perirhinal cortex in brain slices. B, Layer II/III fEPSP amplitudes (normalized to the maximal amplitude) after stimulation of temporal layer II/III input with different stimulus intensities (n = 9 for both genotypes). C, Paired-pulse facilitation (wt: n = 10; Crtl1 ko: n = 6). D, LTD induced by low-frequency stimulation (n = 6 for both genotypes). Data are presented as mean ± SEM. *p < 0.05, simple main effects.