FIGURE 3.

Balance beam crossing times improve with training. During the initial 12-week training period (yellow box), all weeks are different (^) from more than one proficient timepoint (green box). Weeks −16, −11, and −9 are also significantly different from other training timepoint (*). Week −16 is significantly slower than most other timepoint. This may be because there were 27 trials that took longer than 3 s, including six failures due to crossing times that exceeded 10 s. In weeks −11 and −9, crossing times were significantly faster and fall below the cut-off time for proficiency, suggesting improvement in training. Taken together, these data show that extended training does produce a measurable improvement in crossing time and underscores the importance of training prior to experimental treatments. The final week of baseline data (blue dashed box) was used as the baseline for crossing times for 5 weeks after noise exposure (Figure 5). The data from Figure 5 are also plotted for comparison with the training data. Although control rats continue to show stable and proficient balance beam crossing times, noise exposed rats’ crossing times become slower, reaching mean crossing times similar to training timepoint.