speech and hearing science final

Cochlear nerve

transmits auditory impulses from cochlea

vestibular nerve

transmits vestibular impulses from the vestibular system

ascending auditory pathway

connection between the cochlea and the auditory cortex

ascending

sensory, traveling from periphery to central nervous system

cochlear nuclei

• located in the medulla oblongata

• the first brain structure of the central auditory pathway

• receives coded sound from the
  cochlea: after exiting the cochlea, the cochlear nerve enters the brainstem and synapses with the cochlear nuclei

superior olivary complex

• located in the pons

• analyzes intensity and time-of arrival differences between the ears: beginning of sound localization

inferior colliculus

• located in the midbrain

• end point of brainstem nuclei outputs

• vertical and horizontal sound location

• generates acoustic startle response
  (rapid contraction of facial muscles
  evoked by sudden loud noises), orients the body towards relevant stimuli, and discriminates pitch and rhythm

medial geniculate gyrus

• located in the thalamus

• relay point between the brainstem nuclei and the auditory cortex

auditory cortex

• areas of auditory reception and perception in the temporal lobes of both hemispheres

• superior temporal gyrus (Heschl’s gyrus)

auditory cortex tonotopic organization

orderly representation of frequency
created in the cochlea is preserved all the way to the auditory cortex

right ear advantage

stimuli more correctly from the right ear than the left because of left hemispheric dominance for speech processing

dichotic listening of speech sounds

psychological test used to study left-
hemispheric dominance for speech processing (lateralization of brain function within the auditory system)

virtual world

resembles real world the real world, but it is not its exact projection

illusions

sensory misinterpretations that are not resolved even with additional input

auditory illusions

sensory misinterpretations in the auditory sphere