Changes in release sites contacting developing adult-generated GCs. (A) Potency values obtained for the same neuron as in Figure 5C. Upper trace for each class: mean potency for first and second stimuli (for successful responses only). Bottom trace for each class: AMPAR-mediated EPSC amplitude in response to the first stimulation was scaled (black) to potency values obtained for AMPAR-mediated EPSC amplitude (gray). This scaling shows the difference between AMPAR-mediated EPSC amplitude and potency values for AMPAR-mediated EPSC amplitude after the second stimulation. Note that class 3 cells have the greatest difference. Scale bar = 10 ms, 5 pA. (B) Potency ratio (for successful responses only) as a function of AMPAR-mediated EPSC amplitude ratio (successes and failures). Horizontal and diagonal dashed lines indicate an increase in the probability of release at single or multiple release sites, respectively. The linear regression line fitted to all data points for each class is shown in black. P < 0.05 indicates significant deviation of the slope from zero. (C) Comparison between observed (Exp) and predicted (Poisson) potency ratios. Predicted values were obtained using a Poisson model. Note that a significant difference was only observed in class 3 cells (*P < 0.05). Data are from the same cells as in Figure 6B.