Actogram
Multiple periods are plotted modulo 24 hours in the diagram below, aligned vertically. (This is a user specified variable in CATkit.) Mean, amplitude and phase can be found on an actogram. Phase can be found by plotting the slope of the onset of (whatever is being measured). (Refinetti)
Compressed actogram: Vertically compressed plot of raw data, showing multiple periods aligned vertically. Gives a general impression of amplitude. Data points can be plotted on a yes/no basis to compress it vertically.
Compressed actogram: Vertically compressed plot of raw data, showing multiple periods aligned vertically. Gives a general impression of amplitude. Data points can be plotted on a yes/no basis to compress it vertically.
Actogram is a standard method used to visualize periodicity at a macroscopic level (Figure 8). An actogram comprises multiple rows, each row displaying a selected length of time. The alignment of data at a selected period gives a rough assessment of the period at a glance. A distinct vertical edge, as seen in Figure 8, shows activity beginning at the same time in each cycle, indicating the selected width of the Actogram (or folding period) is roughly equivalent to the period in the data.
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A diagonal from upper left to the lower right, as in Figure 9, means the period in the data is longer than the period specified for the actogram (onset activity is later in each cycle).
Even when there is no apparent rhythm, as in Figure 10, the data may still be periodic. Figures 8, 9 and 10 show actograms using the same data set, with different modulus parameters. The Actogram function in CAT can be configured to assess for any period length by changing this modulus parameter. |