Figure 11
From: Methods for serial analysis of long time series in the study of biological rhythms
Motor activity record of a rat submitted successively to LD: T = 23 and DD. The serial periodogram is shown on the right. The periodogram used was the Sokolove-Bushell with a section of 20 days length and a step of 1 day, and the percentage of explained variance is represented in a color scale shown below. The presence of two components is clearly visualized during T23, changing to a unique rhythm in DD with an intermediate period.