**Figure 2.** **Effects of age on ABR amplitude at ultra-high frequency in marmosets.** (**A**–**F**) Scatter plots and corresponding regression lines and regression equations for the relationships between ABR amplitudes (μV) of 36 individual marmosets and age (years) at frequencies of 2 kHz (**A**; R-squared linear=0.0023, P=0.7789); 4 kHz (**B**; R-squared linear=0.0722, P=0.1129); 8 kHz (**C**; R-squared linear=0.0138, P=0.4944); 16 kHz (**D**; R-squared linear=0.05486, P=0.1691); 22 kHz (**E**; R-squared linear=0.1138, P=0.0442); and 32 kHz (**F**; R-squared linear=0.1200, P=0.0385).