Figure 2.

Mice exposed to circadian disruption (CD) light conditions have altered activity rhythms. (A) Picture of the custom-built infrared motion sensor (PIR), showing (above) the sensor as encased in a 3D-printed plastic shell and (below) removed from the case showing the circuit board and components. (B) Representative control light (CL) cycle (black outline), with lights on (pale yellow shading) at 6 AM and lights off (navy blue shading) at 6 PM, and CD light cycle (red outline), with light inversions twice weekly (note that this is the same schedule as shown in Figure 1, but plotted with different start time). (C) Representative single-plotted actograms from 3 cages of female mice exposed to CL over a 6-day period, with vertical black lines indicating activity and each row representing a 24-hour period. (D) Representative single-plotted actograms from 3 cages of female mice exposed to CD over a 6-day period, with black lines indicating activity and each row a 24-hour period. (E) Representative actograms from running wheels of females exposed to CD over a 15-day period, with black lines indicating activity and each row a 24-hour period. (F) Intradaily stability (t = 6.77, df = 4, P = 0.003), (G) intradaily variability (t = 0.40, df = 4, P = 0.71), and (H) relative amplitude (t = 3.52, df = 4, P = 0.025) as calculated from the representative actograms in C and D, presented as mean ± SEM and analyzed with student's 2-tailed unpaired t-tests, *P < 0.05 and **P < 0.01.