L2 pyramidal neurons receive diverse excitatory inputs. A, Average light-evoked EPSCs for the different inputs, recorded in voltage-clamp at +40 mV in control conditions (solid lines), after wash-in of 10 μm CPP (long-dash lines) and subsequent addition of 10 μm NBQX (short-dash lines). Arrows indicate the time of light pulses. B, Quantification of the data in A, expressed as a fraction of control EPSC for each condition. C, AMPA/NMDA ratios from the data in A.