Figure 1.
Free-running and synchronized rhythms, with and without running-wheels.
Double-plotted actograms of Tb, gross motor activity and wheel running of a representative individual (#69). Black bars indicate the moments in which Tb rose above 36.2°C (left), gross motor activity rose above 50 counts (middle) and in which wheel running revolutions were detected (right). Gray and white backgrounds represent darkness and light hours, respectively. Orange line indicates the day in which the running wheel was removed. Red dashed lines indicate the onset of the free-running rhythms in the first DD exposure. Rhythms then synchronize to the LD cycle and upon reestablishment of DD, the phase of the onset is determined by the previously synchronized rhythm, not the one projected by the red line. This is indicative of entrainment of the circadian oscillator by the LD cycle, as opposed to masking of the output rhythms.
Table 1.
Periods of the Tb rhythm in DD and phase relationship between wheel running and Tb rhythms in LD.
Figure 2.
Temporal relationship between Tb and motor activity rhythms.
Waveforms of Tb (red) and gross motor activity (black) rhythms of three individuals under LD 12∶12 (lights on at 07:00 am), with (left) and without (right) running-wheels. Each point represents the average of 10-day measures for the corresponding time of the day. Horizontal lines indicate the mean of the total values obtained for each variable and vertical gray line represent the standard deviation for Tb for each time over the 10 days.
Table 2.
Range of oscillation of Tb rhythms synchronized to the LD cycle.
Figure 3.
Gradients of linear regression of Tb and motor activity in different times of the day.
Average gradients of the linear regression model of Tb and motor activity (integrated over 20 min) of nine animals under an LD cycle. Regressions were performed, for each animal, in 2h-windows, using data from 4 days when they had access to a running wheel and from 4 days when the wheel was absent. Gray lines indicate the standard deviation. The bar above the graph represents the light (white)/dark (black) cycle.
Figure 4.
Comparison of the daily Tb rhythm before and after the demasking treatment.
Waveforms of raw (left) and demasked (right) data from three animals with access to a running wheel under LD 12∶12 cycle. Each point represents the average of 8-day measures for the corresponding time of the day. Horizontal lines indicate the mean of the total values obtained for raw and demasked Tb and vertical gray line represent the standard deviation for Tb for each time over the 8 days. Above each waveform are the range of oscillation values. The numbers on the left are the codes for each animal.