Figure 3
The DMP and the DAMP co-reset.
(a) Top: the propensities for forward and backward locomotion of wild-type animals during the first five DMP cycles following a 0.4 sec mechanical stimulus that terminated at t = 0. Bottom: the propensity for forward locomotion aligned at the onset of the stimulus. The brief stimulus evoked a mild forward response. Data shown here was reproduced from71. Top (averaged by Boc) and bottom (averaged by stimulus) traces were plotted with the same time scale and each top 50 sec epoch was positioned at approximately its correct location along the continuous time axis. Inset: a histogram of the delays of the first DMP cycle following the mechanical stimulus. As previously reported12, the stimulus resets the pacemaker such that most cycles initiate around at t = 60 sec. (b) Same as (a), but for a 15 sec mechanical stimulus that terminated at t = 0 and evoked a strong forward response. The longer stimulus reset the DMP pacemaker and did not detectably affect DMP body contractions (grey traces). DAMP cycles remained synchronized with the DMP, but the amplitude of the backward motion peaks was inversely correlated with the overall propensity for forward locomotion. The numbers of stimuli assayed are depicted in parentheses. Thin lines depict mean ± s.e.m. Double asterisks depict significant differences from a histogram of first cycle times after a mock stimulus or significant differences in peak propensities for backward motion as compared to the fifth cycle after the stimulus (p < 0.01).
