There exists a misconception that ears are nothing more than the “eyes for hearing,” but sound contains completely different set of information about the world than light.
Light accompanies us all the time, but a sound indicates that something has changed. Human auditory system processes sounds in a different way than the visual system does light.
Our auditory system specializes in collecting data about the fourth dimension. While sight informs us about where something is located, hearing’s role is to let us know when something is happening.
earing time resolution is much better than vision time resolution, for example a movie scene which consists of 24 frames per second is perceived by us as one scene, however, 24 knocking sounds per second are heard as a sequence of 24 knocking noises. How is this possible?
Some parts of the auditory system specialize in time measurement, thus the ear’s anatomy is great significance. Whereas light is processed into nerve impulses in a very slow chemical process, which takes place in receptor cells, sound is processed very quickly and mechanically.
1. Detecting sound source
Our ears inform us about the direction the sound we hear is coming from. Some sounds, e.g. echo, do not contain information of value thus we ignore it thanks to a filtration mechanism. The initial calculations, which are used for sound source detection, are made in the brain stem.
Since sound source detection begins in the brain stem, surprising sounds may cause an immediate reaction, such as turning our heads into the direction of the sound. This quick reaction would not be possible if the information collected by both ears wasn't combined and interpreted at a later stage.
2. Finding pitch
All sounds have a pitch which is calculated by our brain. Every sound is a vibration of air, so sound intensity is the effect of the amplitude of vibrations, while the differences in pitch result from the variety of frequencies.
3. Maintaining balance
Our ears are not just for hearing; they help us maintain balance. This is made possible thanks to the internal ear, where the semicircular canals are located.