Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
38 Cards in this Set
- Front
- Back
|
The vesitbular system gives
|
A sense of balance
|
|
|
Frequency
|
The number of compressed or rarefied patches of air that pass by our ears each second
|
|
|
Hertz
|
units for frequency in cycles per second
|
|
|
Pitch
|
Whether a sound has a high or low tone which is determined by frequency
|
|
|
Intensity
|
The difference in pressure between compressed and rarefied patches of air
|
|
|
Another name for the eardrum
|
Tympanic membrane
|
|
|
Entrance into the internal ear
|
Auditory canal
|
|
|
Ossicles
|
Smallest bones of the body
|
|
|
Once a neural response to sound is generated in the inner ear, the signal is transferred to and processed by
|
A series of nuclei in the brain stem
|
|
|
Output from nuclei is sent
|
To relay in the thalamus, the medial geniculate nucleus (MGN)
|
|
|
MGN projects to
|
Primary auditory cortex (A1)
|
|
|
The A1 is located where
|
In the temporal lobe
|
|
|
The outer ear
|
Funnels sound to the middle ear
|
|
|
In the middle ear
|
Variations in air pressure are converted into movements of the ossicles
|
|
|
Three ossicles in the tympanic membrane
|
Malleus, incus and stapes
|
|
|
In the cochlea, the three fluid filled chambers are
|
The scala vestibuli, the scala media, and the scala tympani
|
|
|
Organ of corti contains
|
Auditory receptor neurons (hair cells)
|
|
|
Perilymph
|
1. The fluid in the scala vestibuli and scala tympani
2. cerebral spinal fluid 3. low K+, high Na+ concentrations |
|
|
Endolymph
|
Filled in the scala media
|
|
|
Stria Vascularis
|
1. Active transport processes of endolymph take place here. 2. Reabsorbs sodium and secretes potassium against their concentration gradient
|
|
|
Basilar membrane has two structural properties that determine the way it responds to sound
|
1. Membrane is wider at apex than at base
2. The stiffness of the membrane decreases from the base to apex |
|
|
Von Bekesy determined that the movement of the endolymph makes
|
1.The basilar membrane bend near its base,
2. start a base that propogates toward the apex called a traveling wave |
|
|
Hair cells are located in
|
The organ of Corti
|
|
|
Auditory receptors are
|
The hair cells
|
|
|
Hair cells form synapses on neurons whose cell bodies are located
|
In the spiral ganglion
|
|
|
Depolarization of a hair cell ion channels happen when
|
TRPAI channels on sterocilia tips are opened when the tiplinks joining the stereo cilia are stretched
|
|
|
The entry of K+ depolarizes the hair cell, which opens
|
Voltage gated calcium channels
|
|
|
Incoming Ca2+ leads to the release of
|
Neurotransmitter from synaptic vesicles which then diffuse to the postynaptic neurite from the spiral ganglion
|
|
|
The auditory nerve consists of the axons of neurons whose cell bodies are located
|
In the spiral ganglion
|
|
|
Spiral Ganglion is the first in the auditory pathways to
|
1. Fire action potentials
2. provide all the auditory information sent to the brain |
|
|
Given the outer hair cells far outnumber the inner hair cells it seems paradoxical that
|
Most of the cochlear output is derived from the inner hair cells
|
|
|
Outer hair cells play an important role in
|
Sound transduction
|
|
|
Cochlear amplifier
|
Outer hair cells seem to act like tiny motors that amplify the movement of the basilar membrane during low intensity sound stimuli
|
|
|
Demonstration of how critical a role the amplifier plays
|
Deafness produced by antibiotics is thought to be a consequence of damage to cochlear amplifier
|
|
|
Afferents from the spiral ganglion enter the brain stem from where
|
In the auditory vestibular nerve
|
|
|
All ascending auditory pathways converge into the
|
Inferior colliculus
|
|
|
Tonotopy
|
Systematic organization of characteristic frequency within an auditory structure
|
|
|
Tonotopic maps exist on the
|
Basilar membrane with in the MGN and auditory cortex
|
