Table 1. Synaptic properties of layer 2/3 neurons of V1.

L4 fld stm → L2/3 Pyr wc recording	Inhibitory current		Excitatory current
	young	mature	young	mature
maximal charge (pC, nA* ms)	63.20+/−31.97	147.83+/−75.82 *	0.37+/−0.17	0.44+/−0.23

Synaptic currents were measured by whole-cell (wc) voltage-clamp recordings of layer (L) 2/3 pyramidal neurons and stimulating presynaptic inputs. Maximal charge was measured using the L4 field stimulation (fld stm) configuration shown in Figure 2A (inhibitory: young, n = 13, mature, n = 12; excitatory: young, n = 13, mature, n = 12). For paired recordings, either presynaptic parvalbumin interneurons (Pv+; young, n = 14; mature, n = 19) or presynaptic pyramidal (Pyr) neurons (young, n = 10; mature, n = 10) were stimulated as indicated. +/− std. dev.