Hearing
The human ears main function is frequency analysis. Sound [see page 4, enters] through the outer ear, passes through the ear canal and hits the ear drum (tympanic membrane) and passes into the cochlea which passes it to the brain through the auditory nerve.
The hearing system includes the:
| Section | Construct | Purpose |
|---|---|---|
| [see page 4, Pinna] | Ear Entrance | Protection and direction estimation |
| Malleus, Incus and Stapes | Middle Ear | Amplify incoming sound |
| Cochlea | Inner Ear | Sound waves -> electrical nerve impulses |
Direction Estimation
The slight deviation in how far the sound travels between your 2 ears (as indicated by the pinna) indicates the direction the sound is coming from.
This generally only works for high frequency sounds.
Purpose of 2 Ears
- Localisation - Through either inter-aural time differences (gap between triggers) and inter-aural level differences (change in amplitude between triggers). See equations for time differences [see page 18, here].
- Listening in complex acoustic environments
- Auditory Scene Analysis