Examples of IAP for simulated, AVCN, and MNTB recordings of spontaneous activity.

<p>The left column shows voltage traces (black) and trigger levels for complex (red) and candidate waveforms (orange) for each unit. The corresponding average complex waveform (black) and its pointwise standard deviation (gray) is depicted in the middle column. The trigger potential (TP) (MNTB: presynaptic spike, AVCN: postsynaptic potential, probably the EPSC) is also indicated. The right column shows the histograms (orange) generated by triggering at the height of the TP (after aligned subtraction of the average complex waveform). Further the interspike interval histograms of the complex waveforms are shown, mainly for visual comparison. For the simulated data (A2, B2) the histograms reflect the failure containing condition by a decrease in CritWin (A2), and conversely the lack of decrease in the two unit condition (B2). Guided by the results from the known datasets, the AVCN data (C2, D2) can be interpreted: A substantial number of cells exhibited histograms similar to the cell in C2, suggesting failures of transmission, while the remaining cells showed histograms similar to the cell in D2. If a decrease occurred, its timing was predicted by the ISI histogram (blue). In the MNTB (E2, F2, G2) the most frequent finding was the absence of iP at the TPs height, leading to an empty histogram as in E2. Most of the units with iPs of sufficient height, exhibited no decrease of the histogram in CritWin, as in F2. In a small fraction of recordings a decrease was observed, yet, this could be accompanied by unusually high variability in timing from the presynaptic to the postsynaptic side as in G2 (see individual trace in middle column). IAP classified the recordings in A,B, and G as <i>Dep</i> and the remaining as <i>no Dep</i>.