Week 7 Flashcards
What is the structure of the basilar membrane near the base of the cochlea?
Narrow and stiff
What is the structure of the basilar membrane near the apex of the cochlea?
Thicker and flexible
Where do high pitches produce more displacement in the cochlea?
Near the base
Where do low pitches produce more displacement in the cochlea?
Near the apex
What does the Organ of Corti contain?
Cilia and tip links
What happens when the hair cells in the Organ of Corti move?
Opens K and Ca channels leading to glutamate release at the auditory nerve
What can cause hair cell damage?
Noise, infections, genetic diseases, aging
What type of frequencies are harder to hear as you age?
High frequencies
In which organisms does regeneration of hair cells occur?
Some fish and some invertebrates
In which organisms does regeneration of hair cells generally not occur?
Mammals
What is the first step in the auditory pathway to the brain?
Out the cochlea via the cochlear nerve
What keeps low and high pitches in separate locations in the auditory pathway?
Ipsilateral connections to the cochlear nuclei
What percentage of auditory information projects to the opposite side of the brain?
Approximately 80%
What is the role of the superior olivary complex in auditory processing?
Processes information from both ears to determine the direction of sound
What is the term for the auditory cortex?
A1
What are the two pathways after the primary auditory cortex?
Dorsal ‘where’ pathway and ventral ‘what’ pathway
What theory argues that different pitches activate different places on the basilar membrane?
Place theory
What does frequency theory argue?
Most hair cells are activated at a frequency similar to the pitch of the sound
What is the auditory system organized by?
Tonotopically organized
What are the two main cues used to locate where a sound is in space?
Interaural intensity difference (IID) and interaural time difference (ITD)
How does the pinna contribute to sound localization?
It helps determine how high or low a sound is
What happens to sound localization abilities when the shape of the pinna is changed?
Localization abilities change until subjects learn to adjust
Where is the olfactory epithelium located?
In the roof of each nasal cavity
How many receptors does the olfactory epithelium contain?
Approximately 5 million
