9. The Auditory System Revised July 21, 2010 The learning
objectives of this chapter are to: - Describe the organization
of the auditory system. In particular, be able to describe the -
Categorize hearing loss as conductive, sensorineural, or central
according to the location of the causative lesion. - Describe
where in the auditory system a unilateral lesion may cause
ipsilateral hearing loss. - Explain hemisphere dominance and why
inability to understand speech is only one type of aphasia. a.
Ear and auditory receptors b. Spiral ganglion and cochlear nerve
c. Central auditory pathway d. Wernicke’s area Lesions of the
auditory system cause - Tinnitus ("ringing" or "tinkling")
(Pronounced TINN-ih-tuhs) - Hearing loss (deafness) Ringing in
the ear: perception of noise in the absence of external sound.
Examples are whistling like a teakettle and roaring like
listening to a seashell. I. EAR AND AUDITORY RECEPTORS The
auditory parts of the ear are the external ear, the middle ear,
and the auditory portion of the