**Figure 3.** **DPOAE threshold and amplitude were not affected by age.** (**A**) Association between age and auditory thresholds determined by DPOAE. Data are presented as mean ± SEM. No significant differences were observed. (**B**–**G**) Scatter plots and corresponding regression lines and regression equations for the relationship between the DPOAE amplitudes (dB SPL) of 51 ears in 36 individual marmosets and age (years) at tone burst stimuli of 2 kHz (**B**; R-squared linear=0.02408, P=0.2769); 4 kHz (**C**; R-squared linear=0.00085, P=0.8391); 8 kHz (**D**; R-squared linear=0.02160, P=0.3035); 16 kHz (**E**; R-squared linear=0.07479, P=0.0522); 22 kHz (**F**; R-squared linear=0.00754, P=0.5446); and 32 kHz (**G**; R-squared linear=0.00488, P=0.6263).