Noise intensity discrimination improves by pooling multiple frequency regions

Evidence

To better understand why the near miss happens, consider the following example. For a pure tone at 2000 Hz presented at 60 dB SL, the JND for intensity discrimination (DL) is approximately 0.9 dB (see Figure 4–12). The JND for this pure tone is not nearly as small as the JND for noise, suggesting that when noise is presented, the auditory system uses multiple frequency regions to discriminate between sounds with different intensities. To illustrate how the ear might be able to improve its detection with increasing stimulus level, we look to the excitation pattern, which provides a psychoacoustical representation of the spectral information available to the ear. — Jennifer Lentz, Psychoacoustics- Perception of Normal…, 826