Activity profiles in food-restricted hamsters exposed to skeleton or full long and short photoperiods.

<p>This figure illustrates the daily profile of wheel-running activity (upper panels: A and B) and general cage activity (lower panels: C and D) over 24 h in food-restricted hamsters exposed to early skeleton (Sk_RF; light grey histograms) and full photoperiods (Fu_RF; dark grey histograms) under long (LP, left panels: A and C) and short photoperiods (SP, right panels: B and D). Data are presented as 2-h intervals per 24 h (ZT captions below X axis indicate the beginning of each of the 12 2-h intervals). Data for ZT5-7 are replotted from <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0126519#pone.0126519.g005" target="_blank">Fig 5</a>. Horizontal white and black bars represent the full photoperiods (14 h of light and 10 h of darkness for full long photoperiod in panels A and C; 10 h of light and 14 h of darkness for full short photoperiod in panels B and D). For a given ZT, pairwise differences between Sk_RF and Fu_RF (<i>p<</i>0.05) are shown with stars. a.u., arbitrary units; Rev., wheel revolutions; Fu, full photoperiod; Sk, skeleton photoperiod; RF, restricted feeding (12-h food access); ZT, Zeitgeber time.