Figure 2

C. elegans episodic swimming exhibited a multi-time scale kinetics. Swimming activity of animals cultured in individual chambers was quantified by a pixel counting method (“Methods”). (A) Chambers in WormFlo are shown with row-column indexes (left figure). Active pixels (intensity difference > 12 in the range of − 256 to 256) between time point [t] and time point [t + 1] are shown in red pixels in the upper right image and in yellow pixels in the lower right image, respectively. The animal in chamber id 54 moved while the animal in culture chamber id 66 did not move from time [t] to [t + 1]. (B) Active pixel numbers are shown on the y-axis as an index of swimming activity with culture time is shown on the x-axis. Six-day temporal activity decay patterns were classified into Long-, Mid-, and Short-activity classes by two criteria; average activities during the early half of the recording period (first 3 days) and the ratio of average activity in the early half to that in the late half of the recording period (see “Methods”). (C) Swimming activities of a representative animal in various time scales; full recording time scale (10⁷ timepoints) at the top. Each of the lower panels are a × 10 magnification of the first tenth of its upper panel (red area). Activity threshold at 12 pixels/frame is shown by a red horizontal line in the 5-s scale. Animal activities at 6 day-, 1 day-, 1 h-, 10 min-, 1 min-, and 1 s-scales are shown.