Synaptic fEPSP responses evoked and recorded in the s. radiatum layer of Hirano Body and control mice. Insets are averaged fEPSP sweeps for both control and Hirano Body groups. The stimulus artifacts are truncated at 3 mV in the vertical axis, and the sweeps are 100 msec in duration in the horizontal axis. A) Stimulus-response curves for both Hirano Body (filled circles) and control mice (open circles) at the indicated stimulus intensities. B) Paired-pulse fEPSP responses (50 msec isi). The open bar represents the control group (n = 13(7)); the filled bar represents the Hirano body group (n = 8(4)). The paired-pulse ratios were determined by dividing the slope of the second pulse by that of the first (**, p < 0.001, unpaired t-test). Error bars show mean ± SEM.