Hearing, speech perception Flashcards
3 stages of speech chain> (3)
1>how speech is produced–>articulatory phonetics
2>how speech is recorded–>acoustic phonetics; phonetics transcription
3>how do people listen to speech–>speech perception; auditory phonetics
hearing & perception>
-pitch as perceptual construct (related to f0 but not direct correspondent)
-filtration of background noise (our perceptual system can filter loud background noise)
What anatomy is are perception effects on hearing related to?>
some related to ear processing; some related to how brain processes sounds
peripheral auditory system=
auditory system which is not the brain
peripheral auditory system>summary of stages>
1>sound travels down ear canal>eardrum
2>eardrum moves in response to pressure fluctuations
3 bones in middle ear>
-malleus (hamemr)
-incus (anvil)
-stapes (stirrup)
Cochlea filtering process> (summary)
1>cochlea is filled with fluid & cells which convert pressure fluctuations into electrical signals (which go to brain)
2>different parts of cochlea resonate to different frequency components depending on membrane thickness
3>sound is broken down into different frequency bands
more in-depth cochlea filtering process>
1>sound as pressure vibrations in air (travel>external auditory canal>eardrum)
2>pressure fluctuations make the ear drum vibrate
3>ear drum connected to malleus
4>this transmits sound vibrations through the bones (incus>stapes>) >the cochlea
5>’organs or corti’ in cochlea have tiny hair cells which translate vibrations>electrical impulse (that are carried to brain)
6>depends on membrane thickness, how frequency bands are broken down
percetptions of loudness
- perceived loudness as not the same as pressure fluctuation in the air
-the auditory system COMPRESSRS some amplitude, so we can hear a greater range
pascals used for=
measuring air pressure
decibels=
non linear scale approximating perceived loudness
sones=
an entirely PERCEPTUAL scale
decibels vs sones vs pascals>
-pascals as 10x increase
-decibel as +20 increase
-sone as 4x increase
decibel scale features>
-increases at greater rate at LOWER end of scale; increases less as goes on
-as reaches around [1,000,000Pa] scale flattens out as hard to distinguish (just noisy)
evolutionary reasons for non-linear perception of loudness>
-survival–>environment vs food/animal sounds
perception of pitch>
- response of inner ear to different frequencies is non-linear
- inner ear more sensitive to lower frequencies
cochlear implants=
designed to mimic human functions of ear
cochlear implants-how works? process=
1>sound travels to ear & ‘sound processor’ (which sits behind ear)
2>microphones on sound processor pick up sounds
3>processor converts this to digital info
4>info transferred to implant under skin
5>implant sends digital sound signals down electrode>cochlea
6>hearing nerve fibres in cochlea pick up signals & send>brain
new def for phonolgoy according to sign lang=
meaningless units used in combination
stokoe 1960 findings>
-demstrated that signs in ASL are made up of ABSTRACT PARAMETERS (parallel to phonemes) which can be substituted to build different meanings & signs
stokoe 1960- what parameters did he propose for distinguishing minimal pairs in signs?>
-3 parameters he proposed:
>hand configuration
>location
>movement
original vs current proposal on sequential vs simultaneous processing in signs>
original: all signs NOT processed sequentially but simultaneously
now: some sequentially (hand configuration & location associated with timing of gestures); but also simultaneous sign perception
non-dominant hand signs types of use>
- can be used to continue subj of conversation while commentary is provided
- symmetrical signs (mirrors dominant hand)
-static & meeting (hand is static & place mirrors dominant hand)
prosody of sign language>
movements in sign considered to be SYLLABLES
>emphasis–>magnitude of gesture & eyebrows
>sentence structure–>expressed by clusters of prosodic markers (head tilt, eyebrow lowering, shoulder lowering, large intake of breath)
what acts as evidence for prosodic markers in sign?
evidence from signers perceptions of interpreters signing
assumption that interpreters would need to OVER emphasis prosodic markers (for clarity)
what groups of words have a lot of variation across worlds sign langs?.
numbers
B,,2002 hand signs in US for no1>
> found variation along sociolinguistic dimension such as age, relgiion & ethnicitiy
found phonetic context effects
Black ASL features>*(in comaprison to ASL)
-larger signing space
-greater use of 2 handed signs
-lowered from forehead to cheek
-some individual word variation (christmas, children, hurt, curious)
what is black ASL?>
a dialect of ASL developed out of race segregation in america
phonotactile phonology=
deafblind signers can use sign lang through touch or touch-lip read spoken lang (e.g. touching arm, as nodding)
‘reciprocal tactile communication channels’ (protactile)=
where deafblind people come together to communicate with each other
protactile lang in US phonology=
based on touch movement, location & pressure
other protactile communication can be adapted from=
finger spelling
famous Deafblind communicator>
helen keller
>lost sight & hearing after illnes (19 months)
>learnt to communciate via touch, braille, touch-lip read & speak
sign langs & iconity>
-sign langs tend to have a higher level of iconicity than spoken langs
-units can also be abstract & combine to form new concepts whhich is the pre-condition of phonological structure
sign langs summary of features>
-have a phonologcial structure
-provides another perspective into human lang
-can challenge preconceptions of phonetics & phonology
-can challenge notions of how phonology develops
