Distribution of fast PSP amplitudes in B8a/b from S1 neurons. Both excitation and inhibition are present. After learning, amplitudes of both excitation and inhibition increase, offsetting one another. Conventions within the figure are as those in Figures 1 and 2. Data are shown separately for the three stimulus trains of five spikes each and for the first (A) and fifth (B) PSP in a stimulus train. The overall medians shown are the median amplitudes derived from averaging all three measurements for the first or the fifth PSP elicited by a stimulus train. N = 142 connections were sampled in 28 preparations from naive animals, and N = 100 connections were sampled in 16 preparations from animals that had learned.
