To recognize how a combination of mechanical movements to physiological processes, this method of hearing allows humans to interact with a complex environment and communicate, one must be knowledgeable how the brain hears. Sound vibrations enter the ear canal and contact the tympanic membrane producing it to vibrate. These vibrations in turn pass through three bones assembled together called ossicles. The first bone called the malleus is connects directly to the tympanic membrane. The malleus is coupled with the incus, the second bone that in such a way that moves the last bone called the stapes, which is then connected to the cochlea.
For sound to be transduced into neural patterns, the pushing and pulling of the stapes causes pressure to increase and decrease inside the cochlea. These changes in pressure deform the membranes inside the cochlea, which can then stimulate the organ of Corti. The organ of Corti has receptor cells that are cilia (hair like) protrusions. When vibrations travel through the ear, the mechanical movements are transformed into electrical signals, which stimulate the auditory nerve. The auditory neurons of the inferior colliculus project their axons to the thalamus, which in turn relay the information to the primary auditory cortex. Other areas include the secondary auditory cortex, the posterior auditory field and the anterior field. Additionally other important areas are Wernicke's (area 22) and Broca's (area 44), which is associated with the interpretation and production of language.
