FIGURE 1.

Probabilistic model of mouse behavior. (A) The transitions between the two behavioral states “rest” and “activity” are controlled by the two probability parameters, α and β. The parameters can vary between day and night (or subjective day and night in constant darkness). (B) The behavioral activity data is encoded into sequences of “activity” (behavioral activity > 0) and “rest” (behavioral activity = 0) bins. The encoded sequences are inputs to the model in panel (A). One or more contiguous occurrences of “activity” and “rest” bins are termed activity and rest bouts, respectively. (C) The behavioral activity of an animal is recorded as raw counts in 10 s bins (shown here for a mouse under 24 h light–dark cycles). The corresponding encoded sequence is shown with the same color-coding as in panel (B) for rest and activity. Inset zooms into a 400 s interval during the night (active phase).