Inside the cochlea of a human ear are hundreds of thin cilia. Rather
like an insect's eye, which is made up of hundreds of very primitive
eyes, each cilium responds individually to the pressure variations in
the cochlear fluid caused by sounds, contributing its own primitive
interpretation of the sound to the overall picture. Each cilium
responds to pressure by firing a synapse and sending a bio-electrical
signal along the aural nerve into the inner brain, the journey along
the aural nerve taking about a 25th of a second. While a 25th of a
second's worth of pressure variation information is on the aural nerve,
the brain attempts to match its auditory memory with features in the
pressure variation information. Neural pathways into the brain's
memory of pressure variation patterns are strengthened during this
process, resulting in the brain deciding on what the sound 'is'.
