Population analysis (μ indicates geometric mean) of spontaneous isolated IPSC kinetics. The population of spontaneous isolated IPSCs was divided into two sub-populations based on the bimodal clustering in the correlation scatter plot of rise and decay time (τ1) (see Figure 2A). A) Representative current recording of a pyramidal neuron. Asterisk indicates the identified slow IPSC event and the vertical arrows indicate the randomly selected events. B) Population histograms and Gaussian fits of the decay time constant (τ1) estimates for fast (open, solid, μ = 10 ms) and slow (gray, dashed, μ = 36 ms) event sub-populations are shown plotted on the same axis. Inset plot shows cumulative distribution for the fast and slow populations (solid and dashed lines respectively). C) Population histograms of rise times for both fast (open, n = 714) and slow (gray, n = 240) events. Solid and dashed curves (fast and slow respectively) represent Gaussian fits to the distributions on a log scale (μ = 1.3 ms and 9.0 ms respectively, p < 0.01). D) Duration estimates (rise time + decay time (τ1) or rise time + decay time (τ2) for cases where |A2| > 10pA) are shown for fast (open, μ = 11 ms) and slow (gray, μ = 45 ms) populations. Population distributions and the cumulative distributions (inset) show minimal overlap. E) IPSC amplitudes are shown for fast (open, n = 714) and slow (gray, n = 240) events. Amplitudes for the fast and slow event groups show considerable overlap (μ = 57 pA, 79 pA respectively). F) For events with significant second decay components (|A2| > 10 pA), the second decay time distributions are shown for the fast (open, n = 277) and slow (gray, n = 42) events. Smooth curves are Gaussian fits to the fast (solid, μ = 30 ms) and slow (dashed, μ = 120 ms) population distributions.