Ch. 11 S&P unit 3

Auditory core region

-A1 (primary cortex) -Rostral core -rostrotemporal core -the core region appears to serve the same function as V1 does for vision, allowing for the primary analysis of frequencies

Two general classes of theories of speech perception

-General mechanism theories -Special-mechanism theories

Inner hair cells in the cochlea and auditory nerve fibers

-Inner hair cells in the cochlea form synapses with auditory nerve fibers which are bundled together in the eighth cranial nerve to be sent to the brain

A bat also needs to know if its target is moving left or right and up or down

-LEFT RIGHT DETERMINATION is done by a comparison of the returning echo to the two ears, similar to humans. -UP DOWN DETERMINATION involves comparing sound inputs distributed across its complexly shaped pinnae. Bats can move their pinnae, giving them much better elevation determination than humans. -Altogether, bats use this auditory information to "see" object in the environment

Bats and dolphins and the bisonar system

-bats and dolphins use an active binsonar system -similar to electric sonar systems, bisonar is a process whereby animals emit sounds and then use comparisons of these emitted sounds and their returning echoes to sense the world around them. -Bats hear sounds at much higher frequencies than humans do; most species hear sounds over 100,000 Hz. -Bats can also produce very high-frequency sounds -Together, hearing and producing very high-frequency sounds allows bats to use biosonar

flying insects that obstruct the wave pattern

-because there is such a short wavelength, high-frequency sounds are influenced by small objects that obstruct the wave pattern (like flying insects) --a high frequency wave will hit the insect and cause an echo to return to the bat, allowing the bat to detect small prey --dolphins use the same system to hunt for fish

Dolphin Sonar vs. Bats biosonar

-dolphin sonar is physiologically different but functionally similar -one of the main differences is that dolphins use neither the sustained CF nor the FM call. -instead, dolphins make pulse calls at a constant frequency.

Development of phoneme perception

-during the first 6 months of life, an infant can distingush among all of the phonemes used in a language and can discern subtle differences in sound among equivalent phonemes across languages -6 month old infants can distinguish sounds that adults cannot distinguish, such as the different "t" sounds in the hindi language -Perceptual narrowing

how many vowel and consonants in english language

15 vowels 24 consonants

thermoreceptor range

17 C to 43 C -this is range of temp experienced by our skin, not the actual ambient temperature -above or below these is experienced as pain

humans can hear the range of frequencies from

20 to 20k hertz, range used in music is only up to about 5k hertz -humans can sing between 75 hz and 1300 hz

The head casts an _______________ which changes the loudness and frequency distribution of sound going to each ear

ACOUSTIC SHADOW the acoustic shadow is much more prominent for high-frequency sounds than for low frequency sounds -high frequency sounds will be louder in the closer ear, but low frequency sounds will have approximately the same loudness in both ears

What do auditory nerve fibers from each ear do?

Auditory nerve fibers from each ear go to each side of the temporal love, but more from the right ear go to the left temporal lobe and vice versa

What do the belt and parabelt regions do?

Essentially wrap around the primary auditory cortex and they seem analagous to the extrastriate cortex, doing more complex analyses of the auditory signal.

Evidence of top down processing of speech perception

Phonemic restoration effect-an illusion in which participants hear sounds that are masked by white noise but context makes the missing sounds apparent. word segmentation- the ability of speakers of a language to correctly perceive boundaries between words. top-down- starts with the perception of a bigger picture and breaks it down into smaller segments

How a speech sound is made (anatomy)

Start as air pressure changes in the lungs that are modified by several structures in the neck and mouth to create the sounds necessary for speech 1. air that produces the sound passes through the TRACHEA and LARYNX 2. Vocal folds within the larynx open and close to change the pitch of the sound 3. From the larynx, air passes through the pharynx into the mouth and nose where teeth, tongue, lips, and the UVULA can affect the sound signal 4. Closing the uvula prevents sounds from going up through the nasal cavity, affecting the quality of the sound 5. The sound signal then exits through the mouth and nose

How can we make fast and accurate interpretations of speech signals?

The auditory system uses several tricks... COARTICULATION-phenomenon in which one phoneme affects the acoustic properties of subsequent phonemes CATEGORICAL PERCEPTION- our perception of different acoustic stimuli as being identical phonemes until a certain point at which our perception flips to perceive a different phoneme. Voice ONSET TIME- feres to the production of certain consonants in which there is a difference between the first sound of the phoneme and the movement of the vocal cords

Next step after the superior olive

The next synapse is in the inferior colliculus which projects to the medial geniculate nucleus of the thalamus

What is one of the main methods that people can infer distance of sounds?

We rely on our internal knowledge of the loudness of familiar sounds. -for instance, human voices can be judged as being closer or nearer based on their loudness, but this may lead to errors -FREQUENCY also plays a role in distance perception --high-frequency sounds show a greater decrease in loudness as a function of distance than do low-frequency sounds -The proportion of direct sound to reflected sound is another cue for distance

Dorsal root ganglion

a nerve ending in the skin sends its axon tinto a nerve bundle, where is it joined by many other axons from adjacent nerve fibers the nerve bundles then enter the spinal column and form synapses with bipolar cells as a dorsal root ganglion

speech in the cocktail party effect

a person is om a crowded room with many people having conversations all at once...one person can be listening to the speech of one person but her attention is distracted by the mention of her name across the room... ***suggests that our attentional mechanism does not screen out all perceptual inputs except the one we are focused on**

The McGurk effect

a phenomenon in which vision influences the sounds that a person reports hearing .

the similarity of chroma from one octave to the next can be represented by

a pitch helix

each vowel sound has... formants are...

a specific pattern of formants... formants are the frequency bands with higher amplitudes among the harmonics of a vowel sound

electroreception

ability to detect electric field

endogenous opioids

act as alangesics to reduce pain

FA2

also respond to onset and offset of stimuls more sensitive to higher frequency vibrations -bc of high sensitivity to touch, are helpful in feeling small pressure on the skin, such as when an insect lands on the skin -also used for fine motor control

The phonemic restoration effect

an illusion in which participants hear sounds that are masked by white noise but context makes the missing sounds apparent, providing further evidence for top down processing

Bregman's View of auditory scene analysis

analogous to the principle's of Gestalt Psychology. -the auditory system uses heuristic rules to determine which frequencies go with other frequencies and which sounds are associated with which objects

free nerve endings

another term for noiceptors because of their anatomical structure 2 main types A delta fibers-myelinated noiceptors that conduct signals rapidly and respond to heat and pressure (initial stinging of pain) C fibers are unmyelinated noiceptors that conduct signals more slowly and respond to pressure, extreme temperatures and toxic chemicals -associated with more chronic experience of throbbing pain and may be delayed

Special mechanisms theories

argue that because of the importance of language to humans, special mechanisms have evolved that are specific to speech

the bases of sounds used in human language

both vowel and consonant sounds

Pathways for pain

can be modified by emotion and cognition -to account for this, gate control theory, a model that allows for town down control of the pain signal coming up the spinal cord

nontasters

cannot detect bitter compounds except at v high concentrations

tricks that help the autory system make fast and accurate interpretations of the speech signal

coarticulation categorical perception voice onset

in the brain stem, the auditory tract goes through the_________ and then the ______________________

cochlear nucleus trapezoid body

The three physical features of consonants and how they are produced

consonants are produced by restricted airflow -three physical features are important in determining the sound of a consonant.. 1. Place of articulation 2. manner of articulation 3. Voicing

cochlear nucleus

contains subnuclei with specific functions such as sensitivity to the onset and offset tones at particular frequencies and lateral inhibition

SA2

crucial for object grasping because they have maximum response to steady pressure and are good at stretching from side to side

Damage to Broca's area or Wernicke's area

damage to either area can can aphasia, an impairment in language production or comprehension, respectively

Haptic perception

dynamic process of object identification **wearing gloves**

equal temperament scale

every adjacent note has an identical frequency ratio

experience of timbre

fundamental frequency of musical notes seldom exceeds 5k Hertz, harmonics typically range higher than this -this means that ina ddition to the pitch that is heard, there are other sounds present at higher frequencies, which contribute to the experience of timbre

Which theory of speech perception do most researchers support?

given that nonspeech sounds can influence perception of speech sounds, most researchers support the general mechanism approach.

exploratory procedures

hand movements made in order to identify an object

Brocas aphasics have

have a halted speech pattern and difficulty speaking sentences

SA1 and FA1

have high spatial resolution due to densely packed receptive fields-detect small object and pinpoint objects in space

wernike's aphasics

have largely fluent speech but it may not make sense to listeners because the patients themselves cannot understand what they are saying

decay

how long the fundamental frequency and harmonic remain at their peak loudness until they begin to disappear

Wernicke's area

important for speech comprehension

Broca's area

important for speech production

How do cells organize in the primary auditory cortex?

in TONOTOPIC ORGANIZATION- cells show a maximal response to specific frequencies and these cells are organized in map-like patterns

Why is the trapezoid body important?

in determining the direction of a sound

Formants

in vowels Formants are the frequency bands with higher amplitudes among the harmonics of a vowel sounds, with each vowel sound having a SPECIFIC pattern of formants.

tactile agnosia

inability to identify objects by touch, are no deficits in perception of texture, temp or pain. problem is issue of id not perception -usually only one hand is affected bc of damage to which side of the somatosensory cortex

Remarkable research has found that

individual words could be decoded based only on activity recorded from the auditory cortex- but sentences were less well recreated

turbinates and olfactory cleft and olfactory epithelium

inside the nasal cavity, bony knots of tissue called turbinates ensure that some air is passed upward through the olfactory cleft and land on olfactory epithelium

The cone of confusion

is a region of positions in space in which sounds create the same interaural time and interaural level differences

Sound localization

is based on the comparison of sound in the two ears and is thus analogous to stereoscopic vision

Where does the sound signal go after it has traveled through the trapezoid body? why is this step important?

it goes to the superior olive, which receives input from both ears --this early crossover is crucial for sound localization

depend heavily on smell

macrosmatic

damage to cribifrom plate

may sever the axons, causing impairment in smell -anosmia (smell blindness)=inability to smell -despite regeneration of olfactory receptor neurons, a fractured crib plate may scar over preventing new neurons from reaching the brain

-passive electroreception

means that the fish can detect electric fields by other animals

active electroreception

means that the fish generates its own electric field and then senses disturbances to it, analogous to the biosonar of bats and dolphins

depend more on vision and audition

microsmatic

What theory supports the special mechanism theory

motor theory of speech perception

speech sounds are made by

movements of the vocal apparatus

sensory receptiors in propricoception

muscle spindles, joint receptors, golgi tendon organs -seldom consciously attended to -alcohol consumption more difficult for proprioceptors to give feedback on limb position

perception of consonance and dissonance

musical context and culture

vestibular complex in the brainstem

nerve fibers from the semicirc canals and otolith come together in the vestibular system that then synapses in the vestibular complex in the brainstem -the vestibular complex projects to several areas, including PARIETAL INSULAR VESTIBULAR CORTEX -believed to maintain a representation of head angle, crucial for maintaining balance

nasal septum

nostrils are separated by a wall of cartilage

glomeruli

olfactory rec

coarticulation

one phoneme affects the acoustic properties of subsequent phonemes the consonant and vowel sounds in ba overlap in when they are said the a sound also influences how the b is said and vice versa -different b phonemes are not heard differently --ex of auditory constancy, similar to the concepts of constancy in vision

categorical perception

our perception of different acoustic stimuli as being identical phonemes up to a point at which our perception flips to perceive another phoneme -variation in the signal is not heard, only the phoneme is heard -then, at a certain point, the variation is too much and a different phoneme is heard

olfactory bulb

part of brain just behind nose nerves project hear

orbitofrontal cortex

particularly the right of cortex, receives projections from the piriform cortex and limbic system -emotional nature of odors

ampullae of Lorenzini

passive electroreceptors, located inside the scales along the surface of most fish

tasters

people who can detect bitter compounds

pruriceptors

perception of itching- respond mostly to mild chemical irritants

The medial geniculate nucleus....

projects to and receives feedback from the auditory cortex in the temporal lobe

recording equipment should be able to

record musical notes that exceed frequencies of 5k Hz in order to capture the full timbre of a composition

distance

refers to how far a sound is from us and whether it is in front of or behind us

transposition

refers to the ability of a melody to have more than one version that start on different notes but contain the same intervals ofr sequence of changes in notes

azimuth

refers to the left-right aspect of sound localization

voice onset time

refers to the production of certain consonants (stop consonants) in which there is a difference between the first sound of the phoneme and the movement of the vocal cords -categorical perception

elevation

refers to the up-down aspect of sound localization

FA1

respond to the onset and offset of a stimulus -respond well to low frequency vibrations -especially good at detecting slip, when an object is sliding accross surface of the skin. Useful in avoiding dropping object and maintaing grib

otolith organs

responsible for detecting accelration of the head and id when head is being tilted during accelration or head tilt, hair cells in the otolith bend, giving info about motion or head tilt

vestibular system

responsible for perception of balace in semicircular canals and otolith organs located next to inner ear

SA1

responsible for touch perceptions of pattern and texture -responsible or two point thresholds

Consonants are produced by.. 3 physical features important in determining the sound of a consonant

restricted air flow through the pharynx and the mouth Place of articulation- the point along the vocal tract at which the airflow is restricted (tongue, teeth, lips) manner of articulation- how the restriction occurs, whether the lips are pushed together, whether the tongue is at the front, back of mouth etc. voicing- whther the vocal cords are vibrating or not

anterior cingulate cortex

role in emotional pain

presynaptic cells taste

salty or sour

endolymph

semicircular canal is filled w this liquid

olfactory receptor neurons

serve as olfactory transducers as a particular odorant comes into contact with the tip of the cilia, triggering a neural signal to be sent to the olfactory bulb

scale

set of ordered note starting and ending with the same note one octave higher

Trigeminal nerve

some odorants also cause reactions in the somatosensory system -aspect of olfaction is mediated by the trigeminal nerve, which transmits information about the feel of an odorant, such as the cooling sensation of menthol

Spatial segregation

spatial segregation is the process whereby sounds that overlap in harmonic structure are grouped together, whereas sounds that do not overlap in harmonic structure are not grouped together

differences between music and language perception obscure the parallels between music and manguage

speech perception is based on the inference of subtle differences in the patterns that produce different vowels and consonants, whereas music focuses on pitch and pitch contrasts -neural evidence that music extends beyond what is sung... suggests language and music diifferences: language in the left hemisphere and music on the right

Speech...

speech perception most vital function of the auditory system -needs to be understood rapidly

chroma

subject quality of a pitch -notes that are one octave apart are of the same chroma

olfactory epithelium also contains

supporting cells-metabolic supplies to olfactory receptor neurons basal cells-create olfactory recpetor neurons, die after about one month

receptor cells taste

sweet, umami or bitter

SA mechanoreceptors

tell us about continued pressure on the skin

FA mechanoreceptors

tell us about temporary stimulation of the skin

temporal segregation

temporal segregation is the process whereby sounds that are linked in time are grouped together, whereas sounds that are not correlated with each other are not grouped together

General mechanism theories argue

that speech is no different than any other sound and that the same mechanisms that are used for other sounds are also used for speech.

A drawback of high frequencies is that they lose energy rapidly, meaning....

that their loudness declines rapidly as the sound moves away from the source. -therefore, the initial sound must be very loud -bat calls are often as loud as 140 dB and dolphin calls may be 200 dB. -because the frequencies are outside our range hearing, humans luckily cannot hear these loud sounds.

Auditory scene analysis

the ability to distinguish different sounds in the ambient environment

How can we localize sounds when standing still?

the auditory system calculates differences in loudness and timing between the two ears -The CALYX of HELD is a super-giant synapse that connects two neurons in the auditory primary cortex and is responsible for spatial location -Because these synapses are so big, it allows the extremely rapid transfer of information from one cell in the network to the next

Phonemes linguists use...

the basic unit of sound in human language linguists use the INTERNATIONAL PHONETIC ALPHABET which provides a unique symbol for each phoneme

Attack

the beginning buildup of a note -timbre is affected by how quickly an instrument expresses all of its frequencies and if there are any differences in the onset of harmonics

functionality of categorical perception

the category of what makes each letter and allows us to extract relevant phonemic information from individual differences in speech

The spectral shape cue

the change in a sound's frequency envelope created by the pinnae

Interaural level difference

the difference in loudness and frequency distribution between the two ears

Target range (bats)

the distance of a predator from its potential target, determined by timing an echo's return -size of an object is also determined by returning echoes. --larger objects produce bigger echoes

speech without vision was rare until

the invention of telephones

when a phoneme is changed

the meaning of the utterance is changed

What is the first area that receives input from the medial geniculate nucleus?

the primary auditory cortex (A1)

as we change the shape of our mouth and vocal tract (vwls)

the resonance of the sound changes, giving each vowel sound a characteristic pattern of HARMONICS

in human speech perception what is the stimulus

the stimulus is a voice... understanding the acoustics of human voices is essential to understanding speech perception

Interaural time difference

the time interval between when a sound enters one ear and when it enters the other ear -sound coming from the right will enter the right ear a split-second before entering the left ear, vice versa -because our auditory system can detect this difference in timing, we can use the interaural time difference to determine location along the azimuth

key

the tonic note that gies a subjective sense of arrival and rest in a musical piece

A bat and knowing how fast it is approaching its target

they do this so that it can initiate catching behaviors at just the right time -bats determine their rate of approach by measuring the Doppler shift in their calls -Doppler shifts are apparent changes in frequency that occur when there is relative motion between the source of a sound and a detector. -If the returning echo appears to be slightly higher than the frequency of the call, the bat knows that it is gaining on its target

How do bats determine how far away an object is

they know based on how long it takes for the echo to return back to them

Auditory scene analysis rules fall into three basic type

timing space frequency

what kind of processing matches with speech perception

top down processing we hear pauses between individual words because we know where the boundaries between words are -do not hear this listening to russian bc we are not fluent in that language

phonemic restoration effect

top down processing of what one expects to hear overrides input (from cochlea) -if a person is engaging in a secondary task, the illusion of hearing the missing sound becomes stronger, indicating that the phonemic restoration effect occurs at the PREATTENTION stage in speech perception processing - area's in the TEMPORAL LOBE

tuberous recpetors 2

tuned to detect the fields generated by specific electric discharges by that fish which means they can detect differences between smalled fish and larger fish, prey and predators

ampullae of lorenzine

tuned to detect the weak voltage produced by the movements of nearby fish

vowels are produced by

unrestricted airflow through the pharynx and mouth, vibrations of the vocal cords, by changes in the position of the oral cavity, particularly, the shape of the mouth

How do we localize objects in space?

via the auditory system

The McGurk effect

vision influences the sounds that a person reports hearing -ex the video of the peoples mouth not matching up with the voice over (ba da tha) -an error in perception -the integrative area that drives the mcgurk effect seems to lie along the superior temporal sulcus

2 categories of sounds made by human vocal tracts

vowels and consonants

paradoxical heat experience

warm fibers also have a secondary peak in sensitivity when exposed to very low temperatures

"what" and "where" in the auditory system

what and where information are separated in the auditory system in a way similar to the visual system -the what system forms the basis of speech and music perception -the where system is responsible for localizing sound in space

evidence for top down processing

-knowledge of specific combinations of phonemes within a language -knowledge of the context of speech sfectacular---> know that they meant to say spectacular bc we know that s and p go together but s and f do not in english

Elevation perception

-our auditory system detects elevation as a function of changes in sound frequency created by the folds of the pinnae -the folds in the pinnae cause slight reverbations that amplify some frequencies and dampen others -the spectral shape cue is the change in a sound's frequency envelope created by the pinnae.

timbre the complex sound created by harmonics

-sound that is complex and created by harmonics

Spectral segregation

-spatial segregation is the process whereby sounds that overlap in harmonic structure are grouped together, whereas sounds that do not overlap in harmonic structure are not grouped together. -A key aspect of spectral segregation is grouping by HARMONIC COHERENCE, which is a strong predictor of what sounds our auditory system will group together. -Harmonic coherence takes precedence over spatial segregation.

Auditory development

-the auditory system develops early. -shortly after birth, infants respond differently to sounds they heard in utero and sounds they did not -the auditory system is functional at about the 25th week of gestation -at two days old, infants can recognize the voice of their mother -However, hair cells and the auditory nerve continue to develop throughout the first few years of life

Why are there different types of biosonar in bats?

Because bats that live in the forest need to avoid obstacles and hunt whereas bats that live in the desert only need to hunt. So they adapted accordingly... -the forest bats tend to use a CF-FM call, which has a constant high frequency (CF component) which sweeps down in frequency when it detects potential prey (frequency modulated, or FM). -Desert bats may not have a CF component.

most music starts with

a melody is a rythmically organized sequence of notes, which are perceived as a single musical unit

Tuberous receptors

active electroreceptors

nerve fibers

any particular nerve fiber has a characteristic frequency to which it is most sensitive, consistent with place code theory each nerve fiber also responds to sets of frequencies both higher and lower than the characteristic frequency, referred to as their tuning curve

loudness and locating a sound

at the perceptual level, we use loudness to home in on the spatial location of a sound- the louder the sound, the closer you are to its source

SA2 and FA2

have lower spatial resolution due to a more dispersed receptive fields. They have higher sensitivity to light touch, but are not as precise in determining where on the skin the touch occurs

Auditory cortex

is a large area located in the temporal lobe