Hearing and chemical senses Flashcards
What is the objective measurement and perception of amplitude in sound waves
objective: height
perception: intensity/volume (dB)
What is the objective measurement and perception of frequency in sound waves
Objective: Occurance during a period of time (Hz)
perception: Pitch
What is the perception of complexity in sound waves
timbre, or difference between sounds
If three instruments are being played at a low volume, which will sound the loudest?
the one with the highest pitch (frequency)
If 6 instruments are being played at a high volume, which will sound the loudest?
none, they will sound the same volume
What wave makes up a pure tone?
A sine wave of amplitude and time
Complex tones can be mathematically pieced into ________
sine waves
fundamental frequency
the lowest frequency sine wave of a complex tone, which sets the tone of the soundwave
If a fundamental frequency is found to be 50 Hz, what will be the frequency of the third harmonic
150 Hz
What creates the perception of timbre?
differences in amplitudes of harmonics
Pinna
exposed part of the ear
Tympanic membrane
membrane in the outer ear that vibrates in response to sound waves
Ossicles
Carry vibrations from tympanic membrane and amplify them for the cochlea
what part of the ear is filled with fluid
the inner ear (cochlea)
Which ossicle is against the cochlea
stapes
The base of the basilar membrane is tunes to _______ frequency
higher
The apex of the cochlea is tuned to _______ frequency
lower
Organ of corti
contains the hair cells for sound, translates movement of basilar membrane into neural signals
Why is hearing more fragile than vision
there are much fewer sound receptors
outer hair cells
3 layers, useful for hearing
inner hair cells
1 layer, critical for hearing
If a person is fully deaf, what part of the ear is not functioning?
inner hair cells
Type II fibers send signals from ______ hair cells
outer
Type I fibers have better myelination because they send signals from _____ hair cells
inner
Hair cells rub against ______ to create action potentials
tectorial membrane
auditory nerves travel to the _______ lobe
temporal
Place code frequency processing
sound wave processing based on which area of the basilar membrane responds
temporal code frequency processing
action potentials only fire in synchronicity with the high point of sound wave frequencies
Why can’t humans hear tones above 4000 Hz?
because the hair cells can’t keep up (temporal code) with the frequency of the waves and stop firing
resonant frequencies
frequencies that we are good at hearing
T/F The basilar membrane only responds to the first 3 harmonics
F - responds to all harmonics within human range at the same time
Pitch neurons
Neurons in auditory cortex that give the perception of overall unifies sound
Cochlear implants
stimulate the basilar membrane when the hair cells are not sending the signals themselves
Azimuth
coordinates from left to right at the level of your ears
Interaural time difference
the difference in time for a sound to reach both ears
If a sound is directly in front of you, the interaural time difference will be ___
0
interaural level difference
The difference in sound wave volume experienced by both ears
T/F
- Low frequency sounds can pass through object much easier and have a lower interaural level difference
- ITD and ILD can help figure out sound from any direction
True, false - only azimuth
What helps humans determine elevational direction of sound?
spectral shape of the ears
Where is ITD processed
medial superior olives
where is ILD processed
lateral superior olives
inferior colliculus
area where olives join and determine location of sound
A lesion in the inferior colliculus will cause …
inability to know the direction of sounds
T/F Sound enters at the brainstem
true
Wernicke’s area
language comprehension
Broca’s area
language production
Broca’s aphasia
inability to say things or name items
Wernicke’s aphasia
inability to produce sentences that make sense
which hemisphere of the brain is important for language
left
Which hemisphere of the brain is important for prosody (processing rhythm)
right
Olfactory mucosa
location of smell receptors
Which sense does NOT pass through the thalamus
smell
Piriform cortex
area in temporal lobe that identifies smell
Orbitofrontal cortex
area in frontal lobe that decides whether we do or don’t like a smell
Where are smell signals organized
Olfactory bulb at the base of the brain
How is the amygdala involved in olfaction
emotional reactions to smell
What two flavours do we automatically enjoy
sweet and salty (high in energy)
What flavour do we have an automatic negative reaction
bitter
What area of the tongue has no receptors
middle
T/F Salt taste receptors are more at the tip of the tongue and sweet taste receptors are further back
false - all taste receptors are in all parts of the tongue
where are taste buds located
under papillae
Supertaster
people who have more taste receptors and are more sensitive to taste
non-taster
people who have normal levels of taste
T/F Supertasters are very picky because they are more sensitive to bitterness
true
Insula
area of the primary cortex that identifies taste
Chorda tympani nerve
taste from the front of the tongue
Glossopharyngeal nerve (taste)
taste from the back of the tongue and mouth
Vagus nerve (taste)
taste from the throat
