Figure 1
Mean daily activity counts detected by infrared (IR) motion sensors and by intraperitoneal transponders (e-mitters) in the same adult male rats (n = 11 DMH sham lesions and n = 5 unoperated controls, combined; data from Mistlberger et al [12]). The motion sensors were positioned above the middle of the cage, as in [12,15]. A, D. Mean counts during hours 3–5 of the light period, corresponding to the time that food-anticipatory activity appears when food is restricted to hours 6–10. B, E. Activity during hours 6–10 of the light period, corresponding to mealtime during restricted feeding. C, F. Total daily activity excluding hours 3–10 of lights on (3 h premeal and 4 h mealtime). Abbreviations: Adlib denotes baseline days with food available ad-libitum. 'D' denotes days when food was not provided (also indicated by arrows below panel C). ZT denotes 'zeitgeber time', referring to the number of hours after lights-on each day (ZT0 by convention). Days when food was restricted to ZT6–10 are further identified by the dotted line box in each panel.