Section II. AUDITORY ANATOMY AND PHYSIOLOGY
5-5. BACKGROUND
The human ear serves two major special sensory functions: hearing (auditory)
and equilibrium (balance). The stimulus for hearing is sound waves. The stimulus for
a. Methods of Sound Transmission. The sound stimulus is transmitted in a
variety of ways. Regardless of the actual transmission method, the sound stimulus is
unchanged. Sound may be transmitted by:
(1)
Airborne waves, which have frequency (pitch) and amplitude (loudness
or intensity).
(2)
Mechanical oscillations (vibrations) of structures.
(3)
Fluid-born pressure pulses.
(4)
Electrical impulses along the neurons to and in the brain.
b. Sections of the Human Ear (Figure 5-4). The human ear has three major
parts. Each part serves a specific function in the transmission and reception of the
sound stimulus. The three parts are known as the external (outer) ear, the middle ear,
and the internal (inner) ear.
Figure 5-4. A frontal section of the human ear.
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