Research Paper Volume 13, Issue 9 pp 12587—12606

Neural presbycusis at ultra-high frequency in aged common marmosets and rhesus monkeys

Effects of age on ABR thresholds in marmosets. (A–D) Examples of ABR waveforms of common marmosets aged 2 and 10 years following 80 dB SPL tone bursts at frequencies of 8 and 32 kHz. (E, F) Scatter plots and corresponding regression lines and regression equations for the relationships between ABR thresholds (dB SPL) of 36 individual marmosets and age (years) at frequencies of tone burst stimuli of 8 kHz (E) R-squared linear=0.01168, P=0.5304) and 32 kHz (F) R-squared linear=0.3172, P=0.0003). (G) Relationships between ages and auditory thresholds determined by ABR. Data are presented as mean ± SEM. **P

Figure 1. Effects of age on ABR thresholds in marmosets. (AD) Examples of ABR waveforms of common marmosets aged 2 and 10 years following 80 dB SPL tone bursts at frequencies of 8 and 32 kHz. (E, F) Scatter plots and corresponding regression lines and regression equations for the relationships between ABR thresholds (dB SPL) of 36 individual marmosets and age (years) at frequencies of tone burst stimuli of 8 kHz (E) R-squared linear=0.01168, P=0.5304) and 32 kHz (F) R-squared linear=0.3172, P=0.0003). (G) Relationships between ages and auditory thresholds determined by ABR. Data are presented as mean ± SEM. **P < 0.01; ****P < 0.0001 by two-way ANOVA for significant differences in ABR thresholds between 2-4-year-old and 8-10-year-old marmosets; *P < 0.05, ***P < 0.001 by two-way ANOVA for significant differences in ABR thresholds between 5-7-year-old and 8-10-year-old animals.