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Hear Where We Are by Michael Stocker download in ePub, pdf, iPad

The Middle Ear The middle ear begins at the inner end of the external auditory canal, specifically at the eardrum. It also serves to enhance some sounds through its resonance characteristics. The pinna acts as a funnel to collect and direct sound down the ear canal. Its functions are very important to maintaining the health of the middle ear space. Despite the delicacy of its structure, the tympanic membrane never stops working to transform fluctuations in air pressure known as sound into exact copies in the mechanical domain as vibrations.

The vibratory motions of the tympanic membrane are transmitted to the bones of hearing, also known as the ossicles or the ossicular chain. It too is made up of a series of fluid-filled compartments three semi-circular canals and two larger divisions that contain the sense organs for balance and movement. The organ of Corti responds when the hydraulic energy of the cochlear fluid activates its tiny hair cells to release chemical messengers.

This system begins as the nerve of hearing enters the brainstem. In most people, the left side of the brain processes speech and other complex language functions, whereas tonal stimuli and music are deciphered by the right side of the brain. This is partly what makes them difficult to differentiate, but they are close in spelling. The pinna is made up of a frame of cartilage that is covered with skin.

In most people the

The prize of our inquiry is the vision we behold. The balance mechanism is also called the vestibular system. In addition, there is a transfer of information from one side of the brain to the other.

This system begins

Similarly, if you look at the word here, it spells out the last four letters of the word there, both of which have to do with location. By moving beyond our common assumptions, many of the mysteries of acoustical behavior become revealed, exposing a fresh and fertile panorama of acoustical experience and adaptation. The ossicles are suspended from the roof of the middle ear cavity by tiny ligaments, and the malleus is connected to the tympanic membrane by a ligament, as well. Also in this acoustical realm, certain fishing bats echolocate their prey by reflecting bio-sonar off the surface ripples the fish leave in their wake.

We can think of the central auditory pathways as being organized like circuits. The other structure of the outer ear is the external ear canal. The skin of ear canal has hairs more prominent in some people and glands that produce wax called cerumen also more prominent in some individuals than in others. It contains the bones of hearing, two muscles, a number of ligaments, a small branch of the nerve of taste, and the opening of the Eustachian tube. These messengers then stimulate the nerves of hearing which carry sound stimuli to the brain.