Hearing Flashcards
Sound, a mechanical force, is _____ into neural activity.
transduced
The _____ and ear canal collects low freq. sound waves.
external ear
Three ossicles – _____, _____, _____ – connect ______ to _____.
malleus, incus, and stapes tympanic membrane (eardrum) oval window
Oval window is the window to the _____.
cochlea
Two muscles in middle ear vary linkage of ossicles: _____ and _____.
Tensor tympani muscle
Stapedius muscle
When activated too much, muscles (in the ear) stiffen to _____ loud sounds.
dampen
Thin fibers called _____ run across each hair cell’s _____.
tip links
stereocilia
Effect of sound on stereocilia
1) Vibration makes stereocilia bend, causing _____.
2) The hair cell depolarizes, and calcium influx at the _____ of the cell causes _____ release.
ion channels to open
base
glutamate
Hair cells do not have _____ so therefore do not generate action potentials.
axons
Outer hair cells act as _____.
Inner hair cells act as _____.
Amplifiers
Transducers
The _____ is the first place with bilateral input.
Superior olivary nucleus
Auditory neurons have _____.
tonotopic organization (arranged in pitch order, from low to high)
Auditory cortex cells each have a _____.
preferred frequency
cells ‘specialize’ in what frequency they fire to
Encoding pitch with firing rate of auditory neurons is called _____.
Frequency coding
50 Hz sound causes an auditory cell to fire 50 times a second
the _____ is used when the frequency of a sound wave is too high for any single fiber to fire every cycle.
volley principle (each fiber only fires at a certain point in the cycle. Collective activity is measured)
_____ is when each place on the tentorial membrane has a resonant frequency.
Place coding
_____ are coded by frequency of nerve impulses (up to 50 Hz). This is known as _____.
Low frequencies
Frequency coding
_____ are coded in terms of the place along the basilar membrane which shows greatest activity (over 5000 Hz). This is known as _____.
High frequencies
Place coding
For intermediate frequencies (from 50 to 5000 Hz) _____ is coded through combination of _____.
pitch
Volley & Place mechanisms
_____ signal sound location.
Binaural cues
_____ occur when sounds are heard at a different loudness at the two ears.
Intensity differences
_____ occur when sounds are heard at different arrival times at the two ears.
Latency differences
Accurate localization requires processing both _____ and _____.
Intensity differences
Latency differences
_____ is our main sound localization nucleus.
Superior olive
For high frequency sounds, location is coded by _____ in _____.
intensity differences
superior olive
_____ compares intensity (loudness).
lateral SO
lateral superior olive
For low frequency sounds, location is coded by _____ differences in _____.
latency
superior olive
_____ compares time difference (arrival times).
medial SO
medial superior olive
Auditory cortex analyzes complex sounds in the _____ and _____ streams.
dorsal
ventral
_____ is located in the frontoparietal lobe and involved in sound _____.
Dorsal stream
location (where?)
_____ is located in the temporal lobe and analyzes _____ of sound
Ventral stream
components (what?)
_____ is a disorder of the outer or middle ear that prevents sounds from reaching the cochlea.
Conduction deafness
_____ is a disorder from cochlea or auditory nerve lesions.
Sensorineural deafness
_____ is a disorder caused by brain lesions, with complex results. Associated with neurologic disorders (multiple sclerosis, tumors).
Central deafness
Types of central hearing loss
Cortical deafness
- Pure word deafness
- Auditory agnosia (inability to interpret/recognize)
Auditory hallucinations
_____ results in fluent verbal output, severely disturbed spoken language comprehension. Nonverbal sounds are correctly identified.
Pure word deafness
central hearing loss (cortical deafness)
_____ results in relatively normal pure tone hearing, but inability to recognize verbal or nonverbal sounds (such as ringing telephone).
Auditory agnosia
central hearing loss (cortical deafness)
_____ is the Illusion of complex sound such as music or speech.
Seen in schizophrenia, injury to secondary auditory cortex, or during a temporal lobe seizure.
Auditory hallucinations
Occasionally, auditory hallucinations occur in damage to _____ structures such as superior olive.
brainstem
Inflammation of the middle ear (infection) is know as _____.
otitis media
_____ occurs with dysfunction of the hair cells or auditory nerve.
Sensorineural hearing loss (SNHL)
Symptoms of sensorineural hearing loss (SNHL) include _____, _____, _____, and _____.
Inappropriately loud voice
High frequency loss common
Speech sounds distorted
Background noise makes listening more difficult
Viral infection such as measles and CMV kill _____.
auditory hair cells
More often a gradual onset than sudden onset, _____ is the most preventable cause of deafness.
noise induced hearing loss
NIHL
_____ is the perception of sound in one or both ears or in the head when no external sound is present. It can be single or multi-toned, constant or intermittent, temporary or life-long.
Tinnitus
Although damage to the cochlea causes hearing loss and often _____ tinnitus, _____ maintains chronic tinnitus
initiates
CNS
Prebycusis
age related hearing loss
Tinnitus effects ____% of the population
15
sounds are recognized faster in the _____ hemisphere.
right
