Fig. 1.

Wheel-running versus home cage activity. Raster plots of total wheel revolutions or total RFID-assessed distance travelled in the home-cage plotted in 6 min time bins over 6 consecutive days in standard 12 h light/dark cycles. The raster plots are double plotted on a 24 h cycle with the shaded area representing the dark phase. Activities of representative animals of two different mouse strains A) C57BL/6J and B) FVB/NcrlBRH. Arrows highlight some of the strain-specific differences in activity that can be distinguished using the two recording systems including 1) differences in anticipatory activity prior to lights-off, 2) abrupt change in activity levels half-way through the dark period and 3) sustained activity following lights-on. Differences between the two systems reflect the fact that wheel-running is an elective behaviour while RFID-based data is collected irrespective of the animal’s voluntary cage activities.