Figure 2. cMCMV infection induces auditory and behavioral abnormalities.

(A) Auditory function. ABR was determined in naive and mock- or MCMV-infected mice at W7–8. Representative audiograms in 10 ms from naive and mock- or MCMV-infected pups tested over a range of frequencies (clicks). ABR thresholds are shown on the right. (B) Short-term learning-memory ability. Short-term learning-memory ability was assessed by fear conditioning test at W12–13, and proportions of freezing time and number of freezing events were recorded. (C) Anxiety-like behavior in EPMT. General anxiety to open spaces was evaluated at W12–13. Representative heatmaps of mouse movement tracks and durations are shown. Time spent in the open arms (indicated by white dashed line), percentage of entries to the open arms versus total counts, and number of rearing events were recorded. (D) Anxiety-like behavior in OFT. OFT was performed to assess anxiety-like behavior to open areas. Representative heatmaps of movement tracks and durations are shown. Total traveled distance, percentage of time traveled in the center, and number of rearing events were measured. (E) Spatial learning-memory. Spatial learning-memory abilities were determined by MWM test during W13–14. All mice were trained in the maze for 6 days and tested on the eighth day. Representative heatmaps of movement tracks and durations are shown. Total time of finding the target platform (indicated as a circle in the heatmap) from day 1 to day 6 and proportions of time in the second quadrant on day 8 were recorded. All data were analyzed by 1-way ANOVA test and results are presented as means ± SEM. *, P < 0.05; **, P < 0.01; ***, P < 0.001. Sample size n for each group is indicated.