Figure 4. The EPSC and IPSC charge of interlaminar cortical connections to L4 cells decreases. A, Average maps (aligned to soma, white circle) of connection strength (transferred charge) for excitatory inputs in NR (left) and DE (right) animals. Averages are calculated only for stimulation sites that evoked responses in >10% of cells in our sample. Connection strength is encoded according to the pseudocolor scale. White horizontal lines indicate averaged laminar borders and are 100 μm long. Traces at the right of DE panel are the laminar marginal distributions (red for NR and black for DE). Traces at the bottom of the DE panel are the columnar marginal distributions. Note that NR and DE maps and distributions appear different. B, Distributions of total (left) and mean EPSC (right) input charge originating from L2/3 (top), L4 (middle), and L5/6 (bottom) of NR (red) or DE (black) animals. *, p < 0.05; ***, p < 0.01. The p values for the total charge from L2/3, L4, and L5/6 are 0.06 (NR: mean = 71 pC, std = 52.6 pC; DE: mean = 42.6 pC, std = 42.4 pC), 0.17 (NR: mean = 25 pC, std = 19.5 pC; DE: mean = 35.2 pC, std = 29.7 pC), and 0.37 (NR: mean = 18.5 pC, std = 15.6 pC; DE: mean = 15.8 pC, std = 17.3 pC), respectively. The p values for the mean EPSC charge from L23, L4, and L5/6 are 8.1 × 10−4 (NR: mean = 2.59 pC, std = 1.23 pC; DE: mean = 1.46 pC, std = 0.6 pC), 0.73 (NR: mean = 1.45 pC, std = 0.8 pC; DE: mean = 1.36 pC, std = 0.91 pC), and 0.02 (NR: mean = 0.63 pC, std = 0.33 pC; DE: mean = 0.45 pC, std = 0.28 pC), respectively. All comparisons were done with Wilcoxon rank-sum test or Student’s t test. C, Distributions of fractional EPSC charge originating from L2/3 (top), L4 (middle), and L5/6 (bottom) for cells from NR (red) or DE (black) animals. L2/3: p = 0.015 (NR: mean = 0.62, std = 0.18; DE: mean = 0.47, std = 0.21), L4: p = 0.002 (NR: mean = 0.22, std = 0.13; DE: mean = 0.37, std = 0.15), and L5/6: p = 0.67 (NR: mean = 0.16, std = 0.1; DE: mean = 0.17, std = 0.11). D, Average maps (aligned to soma, white circle) of connection strength (transferred charge) for inhibitory inputs in NR (left) and DE (right) animals. Averages are calculated only for stimulation sites that evoked responses in >10% of cells in our sample. Note that NR and DE maps and distributions appear different. E, Distributions of total (left) and mean (right) IPSC input charge originating from L2/3 (top), L4 (middle), and L5/6 (bottom) of NR (red) or DE (black) animals. *, p < 0.05; ***, p < 0.01. The p values of the total IPSC charge from L2/3, L4, and L5/6 are 0.11 (NR: mean = 413.8 pC, std = 265.7 pC; DE: mean = 285.2 pC, std = 227.7 pC), 0.37 (NR: mean = 87.4 pC, std = 94.3 pC; DE: mean = 115.3 pC, std = 104 pC), and 0.41 (NR: mean = 51.4 pC, std = 63.7 pC; DE: mean = 37.2 pC, std = 35.1 pC), respectively. The p values of the mean IPSC charge from L23, L4, and L5/6 are 1.2 × 10−3 (NR: mean = 7.01 pC, std = 2.69 pC; DE: mean = 4.35 pC, std = 1.87 pC), 0.67 (NR: mean = 3.71 pC, std = 2.53 pC; DE: mean = 3.42 pC, std = 1.33 pC), and 0.67 (NR: mean = 1.58 pC, std = 0.88 pC; DE: mean = 1.44 pC, std = 01.13 pC), respectively. All comparisons were done with Wilcoxon rank-sum test or Student’s t test. F, Distributions of fractional IPSC charge originating from L2/3 (top), L4 (middle), and L5/6 (bottom) for cells from NR (red) or DE (black) animals: p = 0.001 (NR: mean = 0.76, std = 0.1; DE: mean = 0.64, std = 0.14), L4: p = 4.12*10−5 (NR: mean = 0.15, std = 0.07; DE: mean = 0.28, std = 0.11), and L5/6: p = 0.961 (NR: mean = 0.08, std = 0.05; DE: mean = 0.09, std = 0.06).