Thresholds and coding of loudness
Much of the shape of the curve describing absolute threshold as a function of frequency can be accounted for by sound transmission into the inner ear.
Important aspects of loudness coding appear to arise from properties of the basilar membrane and neural encoding of level.
Logarithmic scales (like the decibel scale) are much more appropriate for describing our sensations of loudness than a linear scale.
- For example, we can detect a change in intensity of about 1 dB across a wide range of absolute levels.
Loudness appears to be related to the total amount of firing in the auditory nerve.