Skip to main content
. Author manuscript; available in PMC: 2013 May 7.
Published in final edited form as: Eur J Pain. 2009 Mar 3;14(1):11–16. doi: 10.1016/j.ejpain.2009.01.009

Figure 1.

Figure 1

Operant escape performance of male rats during first trials at 44.5°C and second trials (following 10°C) at 44.5°C. (A) Average plate and platform durations for each of 15 sequential pairs of events (plate and platform durations) during first trials. (B) Average plate and platform durations during second trials. Plate durations gradually diminished as first and second trials progressed, and they did not differ between trials 1 and 2. Platform durations increased considerably as trial 1 progressed through event pair 11, and platform durations increased during trial 2, compared to trial 1. The decline in average plate and platform durations late in trials 1 and 2 results from fewer observations as the trials timed out for some animals. Therefore, the data are replotted as cumulative plate and platform durations across 15 event pairs during first trials (C) and second trials (D). The data are then plotted as platform minus plate durations, providing an event by event measure of pain sensitivity on first trials (E) and second trials (F).