Figure 7. Among the five efference paradigms, a clear difference can be observed between protocols with or without efferent activation during the hair bundle’s recovery. Time-series trendlines of instantaneous frequencies, amplitudes, and inferred MET channel open probabilities are plotted for the hair cell in Figure 5 (A, D, G) and another cell from a different sacculus (B, E, H). All trendlines were normalized by the specific bundle’s steady state value. The five efference paradigms (protocols 0, 1, 2, 3, 4) are plotted in red, gold, green, blue, and violet, respectively. Under protocol 1 and protocol 4, hair bundles return to the oscillatory regime with a higher frequency, lower amplitude, and smaller open probability than those in the three other protocols. Frequency, amplitude, and open probability trendlines with the same efference protocol were averaged together to obtain the mean normalized trendlines in C, F, I, respectively. The protocol 1 and protocol 4 mean open probability trendlines are initially shifted downwards with respect to the protocol 0 trendline (I), but proceed to gradually increase over time, in contrast to the relatively flat frequency (C) and amplitude (F) trendlines. The averaged trendlines reflect data from 18 bundles (5 sacculi). Error bands represent the SDs of data points in a 1 s moving window.