FIGURE 4.

Balance beam crossing scores improve with training. During the initial 12-week training period (yellow box), all weeks except for week −8 are significantly different from more than one other training and more than one proficient timepoint (*). Crossing scores are less variable, even in early training than crossing times, and are more consistent from week to week. By the end of the training period (weeks −11 to −8), crossing scores are more consistent and lower, falling below the cut-off for proficiency, suggesting improvement in training. The final week of baseline data (blue dashed box) was used as the baseline for crossing scores for 5 weeks after noise exposure (Figure 6). The data from Figure 6 are also plotted for comparison with the training data. Although control rats balance beam crossing scores remain lower than noise exposed rats during the post-treatment timepoint, noise exposed rats’ mean balance beam crossing scores do not exceed the cut-off for proficiency. This may suggest that crossing scores are a less sensitive measure of noise-induced motor impairment than balance beam crossing times.