Fig 4. Interspike-times histograms of a combined data set of 7 different cells.

f ₇(δt) (A) and f ₇(δτ) (C), and frequency-count histograms P ₇(k) (for a time interval T = 2.5 s) (B) and P ₇(κ) (for a rescaled time interval $\overline{\tau }=4.0$ (D)) before and after time-rescaling. The histograms f ₇(δt) and f ₇(δτ) are fitted with gamma (solid lines) and exponential distributions (dashed lines). The frequency-count histograms P ₇(k) and P ₇(κ) are fitted with the gamma-count (see text, solid lines) and Poisson distributions (dashed lines). Inset plots in (A) and (C) show the spike rates of the original and time rescaled spike series, respectively. The number of spikes used was 4252.