Familial Circadian Rhythm Disorder in the Diurnal Primate, Macaca mulatta
Figure 3
The intrinsic rhythms of activity and food intake in group-M under constant dim light conditions.
A Left: Stable intrinsic rhythm of activity in monkey M1, with intrinsic circadian period τ = 24.9 h (22 days, shown per Clock Time). Right: corresponding mean patterns of food intake and cognitive performance (mean data profiles, shown per hour of Circadian Time, with CT0 = onset of activity). Red arrow (right panel) - earlier onset of “food through cognitive test” intake, relative to “free-food intake”, reflecting high incidence of incomplete cognitive tests during the day. B,D Power spectrum of activity rhythms within the 0.5–5 cycles per day frequencies (100% = the sum of all the powers shown) for control, M1, M2 and M3. C Raw data recording over 22 days in monkey M3 (shown per Clock Time), illustrating intrinsic asynchrony. Color scheme as in Fig. 1.