Figure 3.

Statistical properties of the IBI time series of patterns A and B. The left columns (a, c, e, and g) represent data for pattern A, and the right columns (b, d, f, and h) display data for pattern B. Data for typical cells are displayed. (a and b) Raster plots of a portion of the time series for pattern A and pattern B. (c and d) Time series of the beat rate, represented as the number of beats per minute. (e and f) Histograms of the IBIs. (g and h) Detrended fluctuation analysis (DFA). The fluctuation function for the detrended IBI time series, F(n), is plotted as a function of the bin size for detrending, n, in a logarithmic plot. The solid circles represent data constructed from the original IBI time series. The open triangles represent data constructed from randomly shuffled IBI time series. The solid lines are the least-squares fits to the original data in the range [10^2.5, 10^4.5] in g and [10^3.2, 10^4.5] in h, respectively. The scaling exponents α in these regions are 0.89 ± 0.03 in g and 0.78 ± 0.03 in h, respectively.