Figure 6. Mechanical arousal of female flies following optogenetic activation during subjective daytime.

(A) Timeline for the experiment. Red light stimulation for 1 hour was provided at CT7 in conditions of otherwise total darkness. Mechanical arousal stimuli at Low Intensity were provided for 0.5 seconds every hour for 6 hours, with the first stimulation taking place 5 minutes into the red light stimulation. All experimental animals in this experiment were females. (B) Sleep patterns across the 3 experimental days. (C) Quantification of activity counts (beam breaks) during the minute pre-arousal compared with the first minute post-arousal, separately for each arousal event. (D) Comparison of the change in activity induced by arousal, averaged across all 6 arousal events. All groups significantly increased their activity due to arousal. (E) Visualization of the % of sleeping flies that were awoken by the mechanical stimulation. For clarity, the sNPF alone and CHR alone control groups were combined into a single Controls group. sNPF/CHR flies appeared to be aroused from sleep at similar rates to Controls, but there were very few sleeping Control animals when arousal was tested at this time of day. Error bars in panel B-D represent the standard error of the mean, and the numbers in parentheses in panel E represent the number of sleeping flies in each group. The total numbers of experimental animals were as follows, for sNPF alone, CHR alone, and sNPF/CHR groups, respectively: 31, 31, 28.