Perception Final Exam: Hearing
are musical scales and intervals universal (experienced the same in every culture)?
No-- scales and interval vary widely across cultures (however octaves are relatively universal)
How does the tuning of the auditory nerve result in the transduction of acoustic energy that is interpreted by the brain?
a low-intensity sine wave tone with a certain frequency will cause certain AN fibers to increase their firing rates, while other AN fibers will continue to fire at their spontaneous rates-- the pattern of firing across all of the AN fibers for that particular frequency is picked up and interpreted by the brain
isointensity curve
a map plotting the firing rate of an auditory nerve fiber against varying frequencies at varying intensities
homunculus
a maplike representation of regions of the body in the brain Homunculus: Somatotopic representation Several sensory maps of body in different areas of S1 and also in S2 areas that have more sensing receptors take up more relestate in S1 -- like then fingers, hands, feet, and lips
what AN fibers are analogous to rods in the retina and why?
high-spontaneous fibers because they are especially sensitive to low levels of sound
sinusoidal waves of sound represent
reflect changes in pressure in the medium sound waves are described in frequency and amplitude of pressure fluctuations
three main auditory structures in the cortex
1- primary auditory cortex (A1) 2- Belt area 3- parabelt area
under normal conditions, what temperature is the skin?
30-36 degrees celsius or 86-96 degrees Fahrenheit
Various kinesthetic pathways also project to the _____ to help coordinate movement
cerebellum
this is the name for a frequency at which a particular auditory nerve is most sensetive
characteristic frequency
loved ones and pain
contact with those we love decreases activation in parts of the brain related to emotions and bodily arousal in response to a threat
amplitude is measured using?
decibles
why are implicit bias important?
determines how positively or negatively we judge and evaluate others this can have a major impact on our decision making and how we interact with others
harmonics
different frequencies that are equal multiples of the fundamental frequencies
how do different tempos result in experiencing music differently?
different tempos have different feels fast--energetic/urgent slow-- relaxed/sad, etc.
How do different cultures vary in musical scales and intervals?
different traditions may use different numbers of notes and spaces between notes within an octave
how is tactile attention like visual attention?
is a limited resource that must be allocated in one way or another-- can be directed voluntarily (endogenously) or reflexively (exogenous) pg 419
how is the cochlea like a optical prism?
its sensitivity spreads across different sound frequencies along its length
in general, how people discriminate speech sounds depends on how ell they can ____ them
label
a harp will cover a ____ range of frequency compared to a bass saxophone
larger
best exploratory procedure for seeing how rough an object is
lateral motion
where is the egocenter for vision and for hearing
vision; between the two eyes hearing- between the two ears (middle of the head)
location of phonation
vocal chords
function of the middle ear
contains the ossicles which amplify sound waves
what sense is older, hearing or vision?
hearing-- developed over millions of years
frequency is measured in ____ and is described as ____
hertz; pitch
two "codes" that help us perceive pitch
1- place code 2- temporal code neurons in the cochlea relay information based on the location and timing of their firing
source segregation is analogous to what in vision?
"Decomposing' an auditory scene consisting of multiple sound sources into separate sound images is analgous to decomposing visual input into various objects in various locations, etc.
other than warm and cold fibers, what kinds of neural fibers mediate perception of cold and warm?
- C fibers - A-delta fibers
Why does coarticulation occur?
- Mass and Inertia (what causes things to move) prevents tongue, lips, jaw, etc. from moving too fast 2- Experienced talkers position tongue, etc. in anticipation of next consonant or vowel, causing coarticulation 3- Coarticulation introduces lots of variation into the "same" speech sounds
pathway for the dorsal column-medial lemniscal pathway (DCML pathway)
- fibers for pressure, vibration, joint, position sense - gracile nucleus - cuneate nucleus - medial lemniscus - postcentral gyrus of the cortex
pathway for the spinothalamic pathway
- fibers for temperature and pain - dorsal root ganglion - dorsal horn of the spinal cord - lateral spiothalamic tract - ventral posterior nucleus of the thalamus - cerebral cortex
what is required to feel two points aw being separate? what fibers are therefore responsible?
- have to have a high density of receptors i the area - receptive fields need to be small - cortical convergence doesn't occur (points are processed in different locations of the brain) spatial acuity threshold are therefore mediated by SA I and FA I receptors that have small receptive fields and high receptor densities
why do computer programs have difficulty recognizing speech?
- lots of variation in speech sounds- context sensitivity due to coarticulation makes it hard for computers to recognize speech can't train a computer to recognize a speech sound, consonant or vowel, without taking into consideration the speech sounds that come before or follow the sound computers perform about as well as a 2 year old
How is our perception for subtle differences in sound different for our perception of subtle differences in brightness for vision?
- more sensitive tot the entire range: the hearing system is always sensitive to the entire range of sound while the visual system has to adjust to lower of higher ambient light levels - better at discriminating differences: we are better at discriminating subtle differences in intensity for hearing better than for brightness can determine differences in loudness by just one dB
SA I or Merkel cell neurite complex responds best to what (what are they most sensitive to)? what are they good at detecting/what is their primary function?
- respond to sustained pressure at a low frequency (less than about 5Hz) and spatial deformation - detect pattern/form and texture
list the categories of discrimitive touch
- tactile - thermal -pain -itch -pleasant touch
other reasons for hearing los
- viral infections - hereditary - aging - excessive exposure to noise
when does intensity work best as a distance cue?
- when the sound source is within on meter of the head or the listener is moving
how can you tell is a fundamental frequency is present or not by looking at sine waves on a graph?
-- ask yourself-- are all of the frequencies even multiples? - need all of the frequencies to be even multiples because harmonics will positively overlap at multiples of the fundamental - the number that all of the frequencies can be divided by is the fundamental frequency ex) 1,000 Hz, 750 Hz, and 500 Hz can all be divided by 250Hz-- 250Hz is the fundamental frequency and so that is the pitch that will be heard when all three frequencies are played at once
where does most of the information coming to the inferior colliculus come from ?
-- most but not all of the information coming to the inferior colliculus comes from the opposite ear the left inferior colliculus listens mostly to the right ear (and vie versa)
how can you tell is a bottle that is dropped breaks or not. consider the principles we discussed for sound segregation
-- onset will vary for a broken bottle (but not an intact one)-- individual shards will make noise independently and have different onsets while an intact bottle will bounce together (only one onset)
how is the what system for vision different from haptic search and the what system for touch?
--Geometric properties of objects are most important for visual recognition-- easier to find a horizontal line out of vertical lines on a visual search (but harder for a haptic search) --Two-dimensional pictures of objects are recognized easily visually but poorly haptically On other hand, visual processing lousy at recognizing things like texture, solidness, etc.
what system of touch
--Material properties of objects are crucial for haptic recognition - can easily find objects based on properties like texture and hardness in a search task
three categories for hearing damage
1- obstruction of the ear canal 2- conductive hearing loss (problems with the middle ear bones) 3- Sensorineural hearing loss (damage to the hair cells)
how do we overcome the problem with cone confusion?
1- pinnae cues 2- head cues 3- upper torso cues
treatments for hearing loss
-hearing aids -cochlear implants
ILD is different from ITDs in what way?
1- ILD generally correlates with angle of sound source, but correlation is not quite as great as it is with ITDs (because head shape irregular) 2- Not much ILD with lower frequencies (because some of the energy is blocked by the head)
membranes that separate the three cochlear canals
1- Reissner's membrane 2- basilar membrane
summary of how sound enters the ear
1- an air pressure wave is funneled by the pinna through the auditory canal to the tympanic membrane which vibrates back in forth 2- the tympanic membrane vibrates the ossicles ending with the stapes which pushes and pulls on the oval window 3- the oval window moving causes pressure bulges to move down the length of the vestibular canal which displaces the middle canal the upper and down motion from the pressure moving through the middle canal forces the tectorial membrane to shear across the organ of corti 4- when the tectorial membrane moves, the stereocilia on top of the hair cells bend initiating the rapid depolarization 5- depolarization of the hair cells results in the release of neurotransmitters which are release into the synapse between the hair cells and the dendrites of the auditory nerve fibers 6- neurotransmitters initiate action potential in the auditor nerve which carries the signal to the brain
what two main structures make up the inner ear?
1- cochlea 2- semicircular canals of the vestibular system canals.
basic pathway of auditory neurons starting at the cochlea and ending in the auditory cortex
1- cochlea 2- superior olive 3- inferior colliculus 4- medial geniculate nucleus 5- auditory cortex
path of sound when sound coming from a location in space-- give all structures starting at the cochlea
1- cochlear nucleus 2- MSO 3- LSO 4- MNTB 5- higher brain centers
two categories of chords
1- consonant 2- dissonant
how do the vowels ee and oo differ in two important ways?
1- ee has a flatter spectrum where there is almost as much energy at the higher frequencies as at the lower frequencies. oo has a greater amount of lower frequencies compared to higher frequencies--- this difference in the amounts of frequencies is measured using tilt 2- peaks for ee and oo are at different locations: - for second peak for ee is at a higher frequencies than the second peak for oo
how did stanely et al see if bias could predict trustworthiness ratings based on race?
1- first had all subjects do an IAT 2- then showed subjects emotional netural black and white faces and asked them to rate the trustworthiness of the face-- this was an explicit measure 3- at the end compared the IAT to the explicit racism score (how trustworthy subjects ranked the faces)
higher order processing of sounds helps with what?
1- good continuation 2- restoration effects
what two things make up the organ of corti?
1- hair cells 2- dendrites of auditory nerve fibers (converge into the auditory nerve)
differences between hair cells and photoreceptors
1- have a lot fewer hair cells compared to photoreceptors (14,000 hair cells and about 100 million photoreceptors) 2- hair cells are faster and more sensitive compared to photoreceptors
two mechanisms that help with localization of sounds?
1- interaural time difference 2- azimuth
three subtypes of somatosensation
1- kinesthesis 2- proprioception 3- touch/tactile (includes pain, pressure, hot and cold, etc.)
two kinds of nociceptors
1- myelinated A-delta fibers 2- unmyelinated C fibers
two "codes" that help the auditory system determine the frequency of a sound
1- place code-- info is coded based on the location where there is the greatest mechanical displacement on the cochlear partition 2- temporal code-- involves timing of neural firing
what factors influence of judgements and behaviors?
1- reasonable ones: - others actually ability, honestly, reliability, etc. 2- bias/prejudice-- which is based on sheer group membership (not reasonable) - like stereotypes (this can also impact how we feel about ourselves
cues for distance of sound?
1- relative intensity of sound 2- inverse square law 3- spectral composition 4- Relative amounts of direct versus reverberant energy
3 parts of speech production
1- respiration 2- phonation 3- articulation
How is sound transmitted into the ear-- give the steps starting with the sounds entering the outer ear:
1- sound is funneled by the pinnae and auditory canal to the middle ear 2- sound passes through the tympanic membrane and causes the ossicles to move and amplify the sounds 3- stapes pushes and pulls on the oval window 4- movement of the oval window causes the fluid in the tympanic membrane to move 5- changes in pressure within the fluid causes a bulge in the vestibular canal that extends from the the base of the cochlea down to the apex (if sound is too intense it will travel through the tympanic canal and be off-loaded at the round window) 6- vestibular canal bulges from the pressure and puts pressure on the middle canal 7- pressure in the middle canal displaces the basilar membrane (which lies at the bottom of the middle canal)-- when the vestibular canal bulges pressure is is placed on the basilar membrane 8- cochlear partition is moved by the soundwaves and the organ of corti translates the sound waves into neural signals
in what ways is ILD similar to ITDs?
1- sounds are more intense at the ear that is closest to the sound source (and less intense in the ear that is further from the sound source) 2- the ILD is largest at 90 and -90 degrees and is existent at 0 degree and 180 degrees 3- between the two extremes, the ILD correlates with the angle of the sound source (BUT--- the irregular shape of the head makes it less precise than ITDs)
ways sounds can sound be separated?
1- spatial segregation 2- temporal segregation 3- spectral segregation 4- gestalt-like principles--- auditory stream segregation 5- using timbre
problems with motor theory of speech
1- speech production is as complex as speech perception (if not more-so)-- can't explain speech perception in relation to speech production 2- nonhuman animals can respond to speech signals in much the same way human listeners can- even though they don't have similarly complex motor speech apparatus 3- categorical perception also applies to things other than speech--- like musical intervals, familiar objects, faces, and facial expressions 4- when we hear speech on the radio or over the phone we can still understand what they are saying despite not seeing them
what are the two major pathways from the spinal cord to the brain?
1- spinothalamic pathway 2- dorsal column-medial lemniscal pathway (DCML pathway)
what two things are measured using spectral graphs that help to explain differences in vowel sounds?
1- tilt 2- frequency of the second peak (look at peak height)
first two auditory localization cues
1- timing (pressure waves arrive at one ear slightly before the other)---- ITD 2- intensity (sound intensity is greater in the ear that is closer to the sound source)---- ILD
two ways that pitch is experienced
1- tone height 2- tone chroma
different manners of obstructions for the articulation of consonants:
1- totally obstructed 2- partially obstructed 3- only slightly obstructed 4- first blocked and then allowed through 5- blocked at first from going though the mouth but allowed to go through the nasal passage
what are two problems with frequency tuning by ANs that complicate how we deal with higher intensity and complex sounds?
1- two-tone suppression 2- rate saturation
Three canals of the cochlea
1- tympanic canal (scala tympani) 2- vestibular canal (scala vestibuli) 3- middle canal (scala media)
How do we use multiple acoustic cues for sound perception?
1- we have a great deal of experience percieving speech sounds throughout our lives 2-
•Can subdivide action for perception into two main categories:
1- what system of touch 2- where system of touch
what 3 things are the 4 kinds of touch receptors sensitive to?
1. Type of stimulation to which the receptor responds 2. Size of the receptive field 3. Rate of adaptation (fast versus slow)
range for human hearing (HZ)
20 Hz to 20,000 Hz
frequency range of musical notes
25-4500 Hz but even higher harmonics are important for timbre (which is critical for music)
musical instruments generally produce notes that are below ______ Hz
4000
how many languages roughly worldwide?
5000
evidence that Humans are born with innate capacity to learn and appreciate music
8 month olds can learn and recognize or distinguish melodies
somatosensation
A collective term for sensory signals from the body coming from the skin, muscles, tendons, joints, and internal receptors
Implicit Association Test (IAT)
A computer-driven assessment of implicit attitudes. The test uses reaction times to measure people's automatic associations between attitude objects and evaluative words. Easier pairings (and faster responses) are taken to indicate stronger unconscious associations.
exogenous spatial attention
A form of bottom-up (stimulus-driven) spatial attention in which attention is reflexively (involuntarily) directed toward the site at which a stimulus has abruptly appeared.
endogenous spatial attention
A form of top-down (knowledge-driven) control of spatial attention in which attention is voluntarily directed toward the site where the observer anticipates a stimulus will occur.
equal loudness curves
A graph plotting sound pressure level (dB SPL) against the frequency for which a listener perceives constant loudness.
inner ear
A hollow cavity in the temporal bone of the skull, and the structures within this cavity: the cochlea and the semicircular canals of the vestibular system canals.
stapedius
A middle-ear muscle that is attached to the stapes-- tensing this muscle will decrease vibrations
ear canal
A narrow region leading from the outside of the human ear to the eardrum. function is to conduct sound vibrations form the pinnae to the tympanic membrane and prevents damage to the tympanic membrane
C fiber
A narrow-diameter, unmyelinated sensory nerve fiber that transmits pain and temperature signals.
C tactile (CT) afferent
A narrow-diameter, unmyelinated sensory nerve fiber that transmits signals from pleasant touch. respond best to slow moving, lightly applied forces may be located only in hairy skin activation promotes oxytocin and endorphin release
inverse square law
A principle stating that as distance from a source increases, intensity decreases faster such that decrease in intensity is equal to the distance squared. This general law also applies to optics and other forms of energy.
Belt area
A region of cortex, directly adjacent to A1, with inputs from A1, where neurons respond to more complex characteristics of sounds
parabelt area
A region of cortex, lateral and adjacent to the belt area, where neurons respond to more complex characteristics of sounds, as well as to input from other senses (like vision)
medial superior olive
A relay station in the brain stem where inputs from both ears contribute to detection of the interaural time difference. this detection begins within the first few months of life
tone height
A sound quality corresponding to the level of pitch. Tone height is monotonically related to frequency. higher frequencies have higher tone heights compared to lower frequencies
haptic virtual environment
A synthetic world that may be experienced haptically by operation of an electromechanical device that delivers forces to the hand of the user.
attractiveness bias
A tendency to see attractive people as more intelligent, competent, moral, and sociable than unattractive people.
motor theory of speech perception
A theory that proposes a close link between how speech is perceived and how it is produced. The idea behind this theory is that when we hear a particular speech sound, this activates the motor mechanisms that are responsible for producing that sound, and it is the activation of these motor mechanisms that enable us to perceive the sound. Motor processes used to produce speech sounds are used in reverse to understand the acoustic speech signal suggests that visually observing someone speaking can impact our auditory perception of the speech
intermediate-sized, myelinated sensory nerve fibers; transmit pain and temperature signals
A-delta fibers
difference between A-delta fibers and C fibers for nociception
A-delta fibers: - myelinated and respond primarily to strong pressure or heat - Intermediate-sized, myelinated sensory nerve fibers; transmit pain and temperature signals - responsible for a quick, sharp burst of pain like when you first touch a hot stove C fibers: - unmyelinated and respond to intense stimulation of various sorts like pressure, heat or cold, or noxious chemicals - Narrow-diameter, unmyelinated sensory nerve fibers that transmit pain and temperature signals - responsible for a throbbing sensation after the A fibers have fired
what part of the brain is activated when we hear sound of any kind?
A1- primary auditory cortex in the temporal lobe
this area of the brain became active when due to suggestion of pleasantness or unpleasantness when people had their hands in water
ACC-- anterior cingulate nucleus
middle ear
An air-filled chamber containing the middle bones, or ossicles. The middle ear conveys and amplifies vibration from the tympanic membrane to the oval window.
high-spontaneous fiber
An auditory nerve fiber that has a high rate (more than 30 spikes per second) of spontaneous firing; high-spontaneous fibers increase their firing rate in response to relatively low levels of sound.
low-spontaneous fiber
An auditory nerve fiber that has a low rate (less than 10 spikes per second) of spontaneous firing; low-spontaneous fibers require relatively intense sound before they will fire at higher rates.
mid-spontaneous fiber
An auditory nerve fiber that has a medium rate (10-30 spikes per second) of spontaneous firing. The characteristics of mid-spontaneous fibers are intermediate between low- and high-spontaneous fibers.
A-delta fiber
An intermediate-sized, myelinated sensory nerve fiber that transmits pain and temperature signals.
where does remaining pressure from intense sounds go when in the ear?
Any remaining pressure from extremely intense sounds is transmitted through the helicotrema and back to the cochlear base through the tympanic canal These "excessive" vibrations are then (we hope) absorbed by another membrane—the round window
why did people report feeling sensation in a limb that is no longer there?
Because S1 & 2 are still there and are undamaged if they become stimulated in relevant areas it can feel like sensations are coming from a missing limb Can also feel like limb sensations when adjacent areas of S1/S2 stimulated
areas of the brain associated with the cognitive aspects of pain
Brain areas related to cognitive aspects: Anterior cingulate: Associated with the perceived unpleasantness of pain sensations Prefrontal cortex: Concerned with cognition and executive control ØThoughts/evaluation of pain/situation very important—e.g., catastrophizing, knowing it'll be over soon, etc.
why is studying the perception of speech in the brain a challenge?
Brain damage follows patterns of blood vessels, not brain function, so of limited usefulness damage may cover just part of a particular brain function -- leaving some function undamaged or, damage can cover a wider range than just speech perception
when is good continuation/restoration less effective?
But if blank gap—people notice; less continuity Comprehension often better w/noise than blank
after touching a hot stove your finger throbs. This is because of ____ fibers firing
C fibers
Narrow-diameter, unmyelinated sensory nerve fibers that transmit pain and temperature signals
C fibers they are unmyelinated so this may be why the response is delayed
if we keep lowering the frequency what might we have to do so that we can hear the sound?
increase the intensity
how to interpret time signatures
Denominator is the size of the note (constitutes one beat) Quarter note= the unit of beat 4 or quarter notes in a measures (4/4) ¾ waltz music A lot of popular music is in 4/4 6/8 is a cousin to ¾
why is rhythm important in music?
Different musical styles tend to emphasize different kinds of rhythms You can hear just a few notes and know what kind of music it is
peaks or formants occur at different frequencies. Thye depend on what two things? What are they important for?
Energy peaks occur at different frequencies, depending on length of vocal tract and articulation qVery important in processing speech sounds, identifying consonants and vowels, etc.
true or false: for both vision and hearing a substantial amount of processing occurs before stimuli hit the cortex
FALSE Auditory system: Substantial processing done before A1 Visual system: Substantial processing occurs beyond V1 Differences may be due to evolutionary reasons
true or false: high frequencies are displaced more towards the tip - low frequencies are displaces more towards the base
FALSE high frequencies are displaced more towards the base - low frequencies are displaces more towards the tip (or the apex)
true or false: racism, sexism, and other prejudicial issues are no longer a problem in todays society
FALSE-- lots of evidence to suggest that while things are better, still there are major difficulties (especially with implicit bias)
•How sensitive are we to mechanical pressure? what parts of our body are most sensitive and which are the least sensitive?
Face most sensitive Trunk and upper extremities (arms and fingers) next most sensitive Lower extremities (thigh, calf, and foot) less sensitive
phase locking
Firing of a single neuron at one distinct point in the period (cycle) of a sound wave at a given frequency. (The neuron need not fire on every cycle, but each firing will occur at the same point in the cycle.)
when is good continuation and restoration more effective?
Fits w/natural situations; often don't notice gap Happens more w/familiar sounds-- when people were familiar with a melody they did a better job of filling in the sound Higher-level context important
how can gate neurons be activated to block pain transmission?
Gate neurons that block pain transmission can be activated in various ways: by extreme pressure, cold, or other noxious stimulation applied to another site distant from the source of pain
why are thermoreceptors important?
Gives information to help maintain and regulate internal temperature (needs to be in narrow range) signal changes in skin temperature respond when they make contact with an object that is warmer or cooler than the skin
Spence, Nicholls, and Driver (2001) performed a cross-modal version of the Spence, Pavani, and Driver (2000) attentional cueing experiment amd Led participants to expect a stimulus to be presented in one modality and sometimes presented it in another. when was the greatest cost? what does this imply?
Greatest cost for invalid cues occurred when tactile stimulus expected but visual or auditory stimulus presented instead Implies that sense of touch may have a very restricted attentional channel
How exactly are neurons in the LSO fine-tuned to interpret differences in sound level?
Have excitatory and inhibitory connections that are wired to compete-- when sounds are more intense at one ear they are better at exciting LSO neurons on that same side (ipsilateral) and inhibiting LSO neurons on the opposite side Excitatory LSO connections: From ipsilateral ear Inhibitory LSO connections: from contralateral ear
consonant chords
Have simple ratios of note frequencies they tend to sound more pleasant include musical intervals (distance between chord fundamental and other notes) of fourths (4:3) or fifths (3:2)
what is head related transfer function (HRTF)?
Head-related transfer function (HRTF): A function that describes how the pinnae, ear canals, head, and torso change the intensity of sounds with different frequencies HRTF also changes depending on different locations in space (azimuth and elevation) Each person has their own "custom" HRTF Based on own body—helps w/localization
measurement for frequency
Hertz 1 Hz is 1 cycle/sec 1 kHz is 1,000 Hz
what is articulation and how does it work?
Humans can change the size/shape of their vocal tract by manipulating their jaws, lips, tongue body, tongue tip, and velum (soft palate) These manipulations are articulation This changes sound frequency distribution -Acts as (differing) filters
what is used to measure implicit bias or implicit attitudes?
Implicit Association Test (IAT) it is a speeded reaction time test
spectrogram
In sound analysis, a three-dimensional display that plots time on the horizontal axis, frequency on the vertical axis, and amplitude (intensity) on a color or gray scale.
how does phonation occur?
Is the process through which vocal folds are made to vibrate when air pushes out of the lungs -- at the larynx air must pass through the two vocal folds which are made of muscle tissues that can be adjusted to vary how much air is allowed to pass through--adjustments are called phonation
how is Javanese music different from the western scale?
Javanese culture: Fewer notes within an octave; more variation in notes' "acceptable" frequencies
haptic perception
Knowledge of the world that is derived from sensory receptors in skin, muscles, tendons, and joints, usually involving active exploration involves processing inputs form multiple sensory systems receiver explores the world rather than passively experiencing it involves using the hands to grasp and manipulate objects
the ____ is where ITDs arrive and the ____ is where ILDs arrive
MSO-- medial superior olive for interaural time difference (ITD) LSO--lateral superior olive for interaural level difference (ILD)
support for the motor theory?
McGurk Effect McGurk and MacDonald (1976) showed that what someone sees can affect what they hear
characteristics of pleasant touch
Mediated by unmyelinated peripheral C fibers known as "C tactile afferents" (CT afferents)-- relatively slow CT afferents not related to pain or itch Respond best to slowly moving, lightly applied forces (e.g., petting) Pleasant aspects/feelings processed in orbitofrontal cortex, not S1 or S2
Which mechanoreceptors are fast adapting?
Meissner corpuscles and Pacinian corpuscles
adaptation and size of the receptor field for Meissner corpuscles
Meissner corpuscles—Fast adaptation, small receptive field
list the 4 kinds of mechanoreceptors for touch
Meissner corpuscles—Fast adaptation, small receptive field Merkel cell neurite complexes—Slow adaptation, small receptive field Pacinian corpuscles—Fast adaptation, large receptive field Ruffini endings—Slow adaptation, large receptive field
Which mechanoreceptors have small receptive fields
Merkel cell neurite complexes and Meissner corpuscles
adaptation and size of the receptor field for Merkel cell neurite complexes
Merkel cell neurite complexes—Slow adaptation, small receptive field
what are musical measures?
Music is organized in subunits defined by time: "measures" contain 3, 4, or 6, beats or notes which form the time signature of the music First meaningful groups= measures Indicated by time signatures (¾ or 4/4) Measures group into larger units (like the verse of the song)-- have a melody that develops through a series of measures
where do we see tonotopic organization?
Neurons that respond to different frequencies are organized anatomically in order of frequency Starts in the cochlea Maintained all the way to primary auditory cortex (A1)-- basilar membrane, cochlear nucleus, superior olive, inferior colliculus, medial geniculate nucleus
how are melodies more like a relationship between successive notes than a specific set of sounds?
Not a sequence of specific sounds but a relationship between successive notes Can change octaves/keys and still be the same melody Notes and chords within melodies vary in duration
stapes
One of the three ossicles. Connected to the incus on one end, the stapes presses against the oval window of the cochlea on the other end.
malleus
One of the three ossicles. The malleus receives vibration from the tympanic membrane and is attached to the incus.
middle canal
One of three fluid-filled passages in the cochlea. The middle canal is sandwiched between the tympanic and vestibular canals and contains the cochlear partition. Also called scala media.
tympanic canal
One of three fluid-filled passages in the cochlea. The tympanic canal extends from the round window at the base of the cochlea to the helicotrema at the apex. Also called scala tympani.
vestibular canal
One of three fluid-filled passages in the cochlea. The vestibular canal extends from the oval window at the base of the cochlea to the helicotrema at the apex. Also called scala vestibuli.
the ____ of ____ is a structure on the basilar membrane that is composed of hair cells (actual initial auditory receptors) and dendrites of auditory nerve fibers
Organ of Corti
how are the ossicles constructed in such a way to be able to amplify sound?
Ossicles have hinged joints that work like levers to amplify sounds—get progressively smaller The stapes has a smaller surface than the malleus, so sound energy is concentrated-- can concentrate energy by moving sound gradually from a larger to smaller sound area concentration of sound will increase 18 fold from when it first arrives at the tympanic membrane to when it finally reaches the oval window Need to concentrate sound energy in part because inner ear consists of fluid-filled chambers --It takes more energy to move liquid than air
Which mechanoreceptors have large receptive fields?
Pacinian corpuscles and Ruffini endings
adaptation and size of the receptor field for Pacinian corpuscles
Pacinian corpuscles—Fast adaptation, large receptive field
decay
Part of a sound during which amplitude decreases (offset) the way a sound ends
attack
Part of a sound during which amplitude increases (onset) the way a sound begins
how is tactile acuity achieved?
People can detect a bump only 1 micrometer high at 75% accuracy! Dot triggers FA I receptors, which also help detect slippage of objects while being grasped Surface with many dots a fraction of a micrometer high can be detected when moved across the skin via FA II receptors deep in skin
•What is the smallest raised element that can be felt on an otherwise smooth surface?
People can detect a bump only 1 micrometer high at 75% accuracy! this is done via FA I receptors
why is it significant that notes that are once octave apart sound more similar to each other compared to sounds that actually are closer in frequency to that initial note?
People will say that the octave sounds more similarity to the presented sound in comparison to a a sound where the frequency is only slightly altered shows that there is more to musical pitch then just frequency-- notes that are one octave apart sound more similar compared to a note that is only slightly different in frequency
proprioception
Perception mediated by kinesthetic and vestibular receptors incorporates sensory input from internal locations in the body (such as your stomach) along with kinesthesis (the system sensing the body position in space)
where is pleasant sensory information processed?
Pleasant aspects/feelings processed in orbitofrontal cortex, not S1 or S2
where system for touch
Provides information about a location in external space that is being touched or a location on the body that is being stimulated knowing where objects are located involves both a frame of reference and the egocenter
humans can hear a wide range of sound intensities. What is the ratio between the faintest and loudest sounds? and what is used to measure this?
Ratio between faintest and loudest sounds is more than 1:1,000,000 Wide range is why we measure sound levels in logarithmic decibel (dB) scale
haptic search
Recognize presence of material properties that are presented haptically to the fingers with a special device
kinesthetic
Referring to perception involving sensory mechanoreceptors in muscles, tendons, and joints.
in a haptic search what kinds of material popped out? what didn't pop out?
Rough among smooth, hard among soft, cool among warm, edged surfaces among smooth surfaces popped out a differently oriented line like a horizontal line among vertical lines didn't pop out-- geometric features are done better for visual searches
which mechanoreceptors are slow adapting
Ruffini endings and Merkel cell neurite complexes
adaptation and size of the receptor field for Ruffini endings
Ruffini endings--Slow adaptation, large receptive field
what areas are responsible for the sensory aspects of pain?
S1 and S2
what kinds of mechanoreceptors are analgous to the rods and cones in vision and why?
SA I and FA I fibers are like the rods and cones one is good for acuity and the other is good for low-intensity stimulation
spatial acuity threshold are therefore mediated by ____ and ____ receptors that have ____ receptive fields and ____ receptor densities. Sensitivity is mainly determined by receptive field ____
SA I; FA I; small; high size
what is Kinesthetic/proprioception? where are these receptors located and what is their function?
Sense of position and movement of your body parts receptors are located in the muscles, tendons, and joints-- they sense where are limbs are and what motions we are making muscle spindle are a sensory receptor located in a muscles that senses muscle tension receptors in the joints and tendons also respond to signals: receptors in tendons respond to muscle tension in the muscles they are attached to and the joints receptors come into play when the joint is bent at an extreme angle
thermoreceptors
Sensory nerve endings under the skin that respond to changes in temperature at or near the skin and provide input to keep the body's temperature at 98.6 degrees Fahrenheit. 2 kinds of receptors: warmth fibers and cold fibers
what is the cochlear partition and why is it important?
Separates middle & tympanic canals Cochlear partition contains Organ of Corti Organ of Corti contains actual auditory sensory neurons-- responsible for converting sound waves into neural signals
true or false: frequencies such as 1,000 Hz to which an AN fiber has almost no response at low intensity levels, evoke quite substantial responses when intensity is increased
True this is related to rate saturation
How sound gets to the brain
Sound waves enter the outer ear and travel through a narrow passageway called the ear canal, which leads to the eardrum (tympanic membrane) The eardrum vibrates from the incoming sound waves and sends these vibrations to three tiny bones in the middle ear. These bones are called the malleus, incus, and stapes. The bones in the middle ear amplify, or increase, the sound vibrations and send them to the cochlea, a snail-shaped structure filled with fluid, in the inner ear. the stapes pushes and pulls the (flexible) oval window attached to the vestibular canal at base of the cochlea. The causes vibrations in the vestibular canal An elastic partition runs from the beginning to the end of the cochlea, splitting it into an upper and lower part. This partition is called the basilar membrane because it serves as the base, or ground floor, on which key hearing structures sit. Once the vibrations cause the fluid inside the cochlea to ripple, a traveling wave forms along the basilar membrane. Hair cells—sensory cells sitting on top of the basilar membrane—ride the wave. Hair cells near the wide end of the snail-shaped cochlea detect higher-pitched sounds, such as an infant crying. Those closer to the center detect lower-pitched sounds, such as a large dog barking. As the hair cells move up and down, microscopic hair-like projections (known as stereocilia) that perch on top of the hair cells bump against an overlying structure and bend. Bending causes pore-like channels, which are at the tips of the stereocilia, to open up. When that happens, chemicals rush into the cells, creating an electrical signal. The auditory nerve carries this electrical signal to the brain, which turns it into a sound that we recognize and understand.
consonants
Speech sounds that occur when the airflow is obstructed in some way by your mouth, teeth, or lips. can be classified by place and manner of articulation and voicing
true or false: chords are named the same no matter what octave they are played in
TRUE--- chords are named the same no matter what octave they are played in-- this is because they are defined by the note frequencies combined to produce them
azimuth
The angle of a sound source on the horizon relative to a point in the center of the head between the ears the azimuth is measured in degrees with 0 degrees being straight ahead- the angle increases clockwise to the right, hits 180 degrees right behind and then decreases to the left
cochlear partition
The combined basilar membrane, tectorial membrane, and organ of Corti, which are together responsible for the transduction of sound waves into neural signals.
lack of invariance in speech sounds
The invariance problem refers to the challenge that listeners face when confronted with acoustic variability in speech sounds as they attempt to map these sounds to few phonological categories in deem, doom, and damn, the "d" is the same but the sound is slightly different due to context of the vowels-- d is the same speech sound but the context provides a lot fo variation
incus
The middle of the three ossicles, connecting the malleus and the stapes.
missing fundamental effect
The pitch listeners hear corresponds to the fundamental frequency, even if it is missing this is because harmonics create reinforced neural responses at fundamental frequency
timbre
The psychological sensation by which a listener can judge that two sounds with the same loudness and pitch are dissimilar conveyed by harmonics and other high frequencies like the "finger print" of a sound-- what makes one sound sound different from another ex) human voice, guitar string, saxophone reed, etc.
spinothalamic pathway
The route from the spinal cord to the brain that carries most of the information about skin temperature and pain. slower of the two pathways and carries most of the information from thermoreceptors and nociceptors
psychoacoustics
The study of the psychological correlates of the physical dimensions of acoustics; a branch of psychophysics.
why are tip links especially important?
These enable extremely rapid regulation of neurotransmitter release, enabling detection of extraordinarily brief time intervals between sounds. they are also relevant for detecting the direction of sound because we need good temporal acuity to be able to tell what direction sound is coming from
How do hearing aids work?
They amplify the sound-- increase sound intensity and also compress the frequency range into a smaller range of intensity to avoid sounds becoming too loud
How did Rosen et al. (2011) developed clever way to control for complexity in speech vs. nonspeech? what were the results of their study?
Took two sentences, presented them as originals, then created nonsense "hybrid" sentences by swapping their amplitude or frequency characteristics Found activity for both left and right superior temporal lobes when listeners heard the hybrid sentences (and for speech and nonspeech) but more activity on left for speech only-- when stimuli was intelligbale speech saw more activity on the left
the ratio of reverberant energy compared to direct energy ____ with distance
increases
temporal code
Tuning of different parts of the cochlea to different frequencies, in which information about the particular frequency of an incoming sound wave is coded by the timing of neural firing as it relates to the period of the sound.
what is one way of measuring two-point thresholds?
Two tactile pulses can be delivered over time, in a manner analogous to spatially separated two-point threshold stimuli people have to determine if the pulses are separate or were delivered simultaneously
auditory masking and what it is used to study?
Using a second sound, frequently noise, to make the detection of a target frequency harder multiple sounds are presented at the same time and then they measure how effective one sound (the masker) is at covering up the other sounds Experiments using masking have supported place code mechanisms of frequency discrimination
how can we tell that music is cultural ?
Western and Javanese musicians' estimates of intervals between notes correspond to the music scale from their culture Six-month-old infants can detect inappropriate notes within both scales but adults better at detecting deviations from their "own scale": - Infants can detect what don't fit in either scale and after time they specialize to their own culture and loose ability to pick up on things as they age - may have fine-tuned ability as one ages and learns their cultural scale
chords
a combination of three or more musical notes with different pitches played simultaneously A grouping of pitches played and heard simultaneously-- creates a larger musical unit can be consonant or dissonant
two-tone suppression
a decrease in the firing rate of one auditory nerve fiber due to one tone, when a second tone is presented at the same time more pronounced when the second tone is a lower frequency than the first
gate control theory
a description of the pain-transmitting system that incorporates modulating signals from the brain shows that there is feedback loops from the substantia gelatinosa (SG) of dorsal horn of spinal cord bottom up pain signals can be blocked via a circuit located in the spinal cord "the transmission of pain acts like a gate- the gat is pushed open by excitatory pain signals and closed by inhibitory inputs"
syncopation
a deviation from a regular rhythm-- like accenting a note that is expected to be unaccented or not playing a note (replacing it with a rest) when a note is expected
cochlear implant
a device for converting sounds into electrical signals and stimulating the auditory nerve through electrodes threaded into the cochlea
tectorial membrane
a gelatinous structure, attached on one end, that extends into the middle canal of the ear, floating above inner hair cells and touching outer hair cells when the tectorial membrane moves, then the hair cells move
threshold tuning curves
a graph plotting the thresholds of a neuron or fiber in response to sine waves with varying frequencies at the lowest intensity that will give rise to a response when the sound is played very faintly or at low intensity an AN fiber will increase its firing in response to only a selective range of frequencies AN are most sensitive to their characteristic frequency (and different ANs have different CFs)
directional transfer function (DTF)
a measure that describes how the pinna, ear canal, head, and torso change the intensity of sounds with different frequencies that arrive at each ear from different locations the relative intensities of different frequencies are continuously changing with elevation and the azimuth-- the sum total of these intensity shifts can be combined to determine the DTF throughout life the DTF also changes as babies grow larger heads and the pinnae increase in size throughout life
what defines a melody?
a melody is defined by the pattern of rises and declines in pitch rather than by the exact sequence of sound frequencies - melodies stay the same even if the octave is shifted-- this is because the step between each note stays the same the tempo also defines the melody-- while the relatively rate of the tempo can change (fast or slow) the duration between notes stays constant- if the duration between the sequence of notes is shifted we will hear a different melody
inferior colliculus
a midbrain nucleus in the auditory pathway
basilar membrane
a plate of fibers that forms the base of the cochlear partition and separates the middle and tympanic canals in the cochlea forms the base for the auditory receptor cells
acoustic reflex
a reflex that protects the ear from intense sounds, via contraction of the stapedius and tensor tympani muscles
cold fiber
a sensory nerve fiber that fires when skin temperature decreases (these are more numerous than warm fibers)
warmth fiber
a sensory nerve fiber that fires when skin temperature increases
define mechanoreceptor
a sensory receptor that responds to mechanical stimulation like pressure vibration or movement
melody
a sequence of notes or chords perceived as a single coherent structure Sequence of notes/chords that unfolds over time considered the heart of a piece of music (everything built around the melody)
round window
a soft area of tissue at the base of the tympanic canal that releases excess pressure remaining from extremely intense sounds
tone chroma
a sound quality shared by tones that have the same octave interval each note on the musical scale has a different chroma (A-G)
organ of corti
a structure on the basilar membrane of the cochlea that is composed of hair cells and dendrites of auditory nerve fibers extends along the basilar membrane and and made up of scaffold cells that support specialized neurons called hair cells and dendrites of auditory nerve fibers that terminate at the base of the hair cells
example of good continuation/restoration for sound in the lab
a target sound has a portion of the tone deleted and is replaced by a loud sound-- listeners will hear the sound as if it continues through the noise
tip link
a tiny filament that stretches from the tip of a stereocilium to the side of its neighbor stereocilia connected by tip links bend together as a set when deflected by the shearing motion of the tectorial membrane
what is the musical helix
a way to visualize musical pitch
neuropathic pain
abnormal processing of pain message; burning, shooting in nature - referred pain may arise from changes to the dorsal horn of the spinal cord or dysfunctional pain receptors in the skin
at about what point can we damage our hearing? At how many decibels might we experience pain?
above 110- damage around 140 is the pain threshold
if your skin temperature goes above 36 degrees Fahrenheit your ___ receptors will start to fire, and if your skin temperature goes below 30 degrees Fahrenheit then youre ___ fibers will fire
above--- warmth fibers below-- cold fibers
what do we mean when we say that Touch sensations are represented somatotopically
adjacent areas on the body are represented in adjacent areas in the cortex
how does the shape of the torso impact how we hear sound?
also the size and shape of the upper torso effect which sounds reach the ear most easily-- because of this, the intensity of each frequency varies slightly according to the direction of the sound
when airflow is obstructed at the alveolar ridge just behind the teeth what sounds are made?
alveolar speech sounds: d, t, n
Why are ossicles important?
amplification provided by the ossicles is important because the inner ear is composed of fluid-filled chambers and it takes more energy to move liquid than it does to move air-- so, the sound waves must be amplified to be able to move the liquid in the inner ear amplification is essential for our ability to hear faint sounds
amplitude reflects the ____ of a sound measured in ___ and is describe as ____
amplitude= intensity measured in dB described as loudness
amplitude or intensity is perceived as _____ while frequency is perceived as ____.
amplitude= loudness frequency= pitch
how does phase locking provide a temporal code for sound frequency?
an AN fiber is most likely to fire at one particular phase of each cycle of the sine wave for higher frequencies where ANs cannot produce action potential fast enough, multiple neurons can encode higher frequencies as a group (volley principle)
when airflow is obstructed at the lips what sounds are made?
bilabial speech sounds: b, p, m
ITDs and ILDs are analogous to what in vision?
binocular disparity
location of respiration
lungs
tonotopic organization
an arrangement in which neurons that respond to different frequencies are organized anatomically in order of frequency neurons throughout the auditory system are arranged based on the frequencies that they are most sensitive ex) neurons that are most senstive to low frequencies lie on the edge of each structure (basilar membrane, cochlear nucleus, superior olive, inferior colliculus, medial geniculate nucleus) and neurors responding to higher frequencies lie on the other edge
superior olive
an early brain stem region in the auditory pathway where inputs from both ears converge another brainstem nucleus that receives inputs from both ears good at preserving the timing of information
Hyperalgesia
an increased or heightened response to a normally painful stimulus can happen after injury -- site can become more sensitive
hair cell
any cell that has sterocilia
ossicles
any three of the tiny bones in the middle ear they include the malleus, incus and stapes
range for human hearing (dB)
around -5db to 130 dB (anything above like 115 dB is damaging to the ears) or 0-140 (what they show in the book)
how do we classify speech sounds?
articulation: - consonants - vowels
what does the isointensity function measure?
as frequency changes (x-axis) it records how much a particular AN spikes (y-axis)
why is there not much ILD for lower frequencies?
at frequencies lower than 1,000 HZ, the head blocks some of the energy from reaching the opposite ear--- ILDs are greatest for high frequency sounds but are greatly reduced for low frequency sounds this is why it is harder to localize bass sounds and why it doesn't matter where you put a subwoofer in a room
axons enter the spinal cord where?
at the dorsal horn which is towards the back of the spinal column
when looking at a threshold tuning curve how can you tell where the characteristic frequency is?
at the lowest point of the curve
explicit bias
attitudes or beliefs that one endorses at a conscious level these take time to develop and evolve slowly with experience
implicit bias
attitudes or stereotypes that affect our understanding, actions, and decisions in an unconscious manner they occur very quickly and are activated as soon as we meet someone implicit bias is harder to change because we aren't aware of them later they can impact slower forming explicit bias
A map of just barely audible tones of varying frequencies. How intense a sound has to be for you to pick it up at all
audibility threshold
efferent fibers
axons traveling away from the CNS - from the brain outward - ex) outer hair cells receive info from the brain and help us determine what to listen for - top down process
difference in attack for for "ba" vs "wa" sounds
ba: sharper attack wa: more gradual attack phase
statistical learning and the learning of words?
babies learned which speech sounds were more likely to occur together they picked up on correlations--noticed that some speech sounds were likely to follow or precede certain speech sounds therefore when they heard something out of the ordinary that didn't fit the pattern the spent more time listening to the non words
why is it hard to create well-controlled nonspeech stimuli for studying how human speech is processed in the brain?
because humans are so good at understanding even severely distorted speech
why is it that listeners will hear the same consonant sound as 'b' following 'ee' as as 'd' following 'oo' ?
because of the contrasts between the spectrum of 'ee' and 'oo' and the spectrum of the following consonant
what do we know about melody development?
begins early in life-- 8-month-olds: Learn/recognize new melodies after hearing them for only 3 minutes 7-month-olds: Learn/recognize differences between Mozart sonata movements
how is the development of speech perception different from vision?
begins very early in development babies begin experiencing speech before they are born --- newborns prefer hearing their mother's voice over other female voices also, infants prefer hearing their native language-- french babies preferred hearing French over Russian
the way a sound begins is called ___ and the way a sound ends is called ___-- these are an important quality of complex sounds
begins-- attack ends-- decay
which mechanoreceptors are used to detect the following vibrations? below 5 Hz 5-50 Hz above 50Hz
below 5 Hz---SA I fibers 5-50 Hz-- FA I fibers above 50Hz-- FA II fibers
what secondary or associative areas are activated when we hear music or speech?
belt and parabelt areas
How is tactile acuity compared to visual and auditory acuity?
best to worst: best--- auditory acuity next best-- tactile acuity worst-- visual acuity
where is the best, lowest frequency of human hearing according to the audibility threshold? what does this mean for the other frequencies outside of this range?
between 2,000 and 6,000 Hz (2-6 kilohertz) the higher and lower frequencies would require larger amplitudes in order to be hear
implications forhaptic virtual environemtns
beyond video games, could enable a surgeon or operator to maneuver a remote robot to practice surgery
how are light waves used in vision and sound waves for hearing similar?
both are sine waves analogous to light waves/vision, all sound waves can be described as combination of (individual frequency) sine waves colors are a combination of different frequncy waves while sounds also are a combination of many sine waves
when do babies start to ignore speech sounds not found in their native language? what study showed this?
by 1 year, babies begin to ignore consonant distinctions not found in their native language just as their parents do but, at 6-8 months english infants were able to pick up on differences in sounds in the hindi language-- could discrimiante all speech sounds (not just english at 6-8 months and then lose the ability to discriminate over time)
after depolarization (when K+ enters the cell) what ion is then enters the cell to result in the releases of neurotransmitters?
calcium
reliably discerning the spectral characteristics of sounds (like for vowels) is analogous to what in vision?
calibrating for spectral compositions of illumination when perceiving color both involve considering contexts
manner of articulation: first blocked, then allowed to sneak through
called "affricates" sounds: ch, j
manner of articulation: partially obstructed
called "fricatives" sounds: s, z, f, v, th, sh
manner of articulation: only slightly obstructred
called "laterals" and "glides" laterals: l, r glides: w, y
manner of articulation: blocked at first from going through the mouth but allowed to go through the nasal passage
called "nasals" sounds: n, m, ng
manner of articulation: total obstruction
called "stops" sounds: b, d, g, p, t, k
how is the Prefrontal cortes (PFC) important for pain perception?
can have thoughts about pain -- how long will is last and how long will it go on - hoping it will be over soon -- "catastophizing"
because of coarticulation listeners ____ use a single feature of sound to identify a vowel or consonant. Instead listeners must use ___ properties of a speech signal
cannot; multiple
afferent fibers
carry sensory signals from receptors to the CNS - inner hair cells
how does the way people change the shape of their vocal tract important for articulation?
changing the size and shape of the vocal tract allows sound passing through to increase of decrease in energy at different frequencies-- we call these effects resonance characteristics the spectra of speech sounds depends on how people configure their vocal tract as resonators
endogenous opiates
chemicals released in body to block release or uptake of neurotransmitters transmitting pain sensation to brain ex) soldiers injured in battle don't feel pain until later
in terms of the azimuth, the angel increases ____ and we measure the azimuth in ____
clockwise; degrees
computers are very limited in recognizing speech because of _____
coarticulation
structures in the inner ear
cochlea, vestibule, semicircular canals
where do all auditory nerve fibers first synapse on the brainstem?
cochlear nucleus (where afferent auditory nerve fibers synapse) afferent= going towards efferent= going away
After only a single synapse in the ____ ____, information from each ear travels to the _____ _____ ___ and ____ ____ ____on each side of the brain stem.
cochlear nucleus--- medial superior olive--- lateral superior olive
a complex structure in which sound waves are transduced into neural signals
cochlear partition
what e structures together are responsible for the transduction of sound waves into neural signals and what are all of these structures together called?
cochlear partition
what thermoreceptor fibers usually tell us about objects and why?
cold fibers usually tell us about objects because most objects are cooler than 30 degrees celsius ex) stone feels cool to touch
one problem with using ITDs and ILDs is?
cone confusion --- there is a region of positions in space where all sounds produce the same time and level differences-- some regions in space produce the same ITDs and ILDs-- elevation adds another dimension to sound symmetrical angels at different elevations may have the same ITDs and ILDs
low-spontaneous fibers are more analogous to the ____ of the retina
cones
How can pain be lessened?
counter-stimulation-- like rubbing an area near the source or can distract from the pain by applying extreme pressure, cold, or other noxious stimulation applied to another site distant from the source of pain-- this is achieved by inhibiting interactions in the spinal cord gate neurons endogenous opiates also can lessen pain
what determines how long it takes for a given sound to decay?
depends on how lone it takes for the vibrating object creating the sound to dissipate energy and stop moving
why are tip links important for auditory acuity-- especially since acuity of hearing is much better than visual acuity?
depolarization of hearing doesn't await a cascade of of biochemical processes such as those in photo-activation in vision. ion pores open when deflection is as little as 1 nanometer -- so this is extremely sensitive- opening of ion pores results form direct connection between stereocilia tip links
How can spectral contrasts be used to explain coarticulation?
despite the lack of acoustic invariance due to coarticulation, spectral contrasts help listeners perceive speech when we process sounds (e.g., a vowel), take into account preceding and following sounds especially the contrast between them---different sounds sound acoustically different due to the preceding vowel can perceive syllables like bah and dah due to relative changes in the spectrum (look at contrasts)
different animals can hear different ranges of sound. ex?
dogs better at hearing higher frequencies (ex: dog whistle) larger animals like elephants and whales are better at hearing lower frequencies
Decibels define the difference between the two sounds in terms of a ratio between sound pressures. How does this ratio work?
each 10:1 sound pressure ratio equals 20 dB so a 100:1 ratio is 40 dB
why does how we her speech sound impacted by what we learn as our first langugage?
each language has 20-40 phonemes and as we learn our native language we specialize to learning and getting good at discriminating those speech sounds and not so good at discerning speech sounds that are not used in our language ex) native Japanese speakers are bad at telling the difference between 'r' and 'l'
tympanic membrane
ear drum a thin sheet of skin at the end of the outer ear canal vibrates in response to sound (moves in response to pressure changes in sound waves) can heal itself if damage isn't too severe
formants of ee vs oo
ee vs oo: both have the tongue high in the mouth but the difference is how far back the tongue is-- for ee the tongue is further forward and for oo the tongue is further back just by looking at the first two formants we can tell what vowel sound is being made
how are ee and oo different?
ee: - relatively flat spectrum - more higher frequencies oo: - tilted spectrum - less energy at the higher frequencies - lower second spectral peak
why is pain complex?
effected by not only sensory stimulation from nociceptors but also is impacted by cognitive, emotional, and chemical influences
____ LSO connections come from _____ ear _____ LSO connections: from _____ ear
excitatory; ipsilateral inhibitory; contralateral
experiment where babies were shown to be good at distinguishing words?
experimenters made up a novel language and babies listened to the language for 2 mins after only two mins babies were good at picking up on non-words and listened to non words longer--- this is likely due to statistical learning
where is the tectorial membrane located?
extends in the middle canal and rests above the inner hair cells and touches the outer hair cells movement of the tectorial membrane causes teh ends of the hair cells to bend and leads to the release of neurotransmitters
pinnae
external ears (outer ear)-- varies among different species (and among individuals--- shape of pinnae makes sound appear slightly different for each individual) funnel-like -- funnels sound waves into the ear canal plays an important role in our ability to locate sound source (some animals can direct their pinnae towards sounds)
true or false: If an AN fiber with a CF of 2000Hz is firing very fast, sound must be 2000Hz
false- the brain cannot rely on a single AN fiber to determine the frequency of a tone multiple ANs with different firing rates are used to determine the tone of a sound
true or false: people always perceive speech sounds as continuously varying
false-- instead people perceive sharp categorical boundaries in speech sounds
true or false: you can't determine the pitch without the fundamental frequency
false: its not even necessary to have all of the harmonics either even if the fundamental is removed, the pitch will still correspond to the fundamental frequency
true or false: 40dB is 2x as intense as 20dB
fasle 10:1 is 20dB and 100:1 is 40dB values increase by multiples of 10
In Implicit Association Test (IAT), easier or ____ pairings are taken to indicate stronger ______ associations
faster; unconscious
what happens to the firing rate when we increase the frequency above the AN's CF?
firing rate will start to decrease a firing rate will increase until the frequency is above the AN's CF--- after the CF the firing rate starts to decrease
How to read the equal-loudness curve to figure out where what something sounds like actually reflects its physical amplitude?
follow the line and see where the number on the x-axis matched the numbers in the middle of the graph
drawbacks of the acoustic reflex?
follows the onset of large sounds by about 1/5 of a second (follows loud sound by about 200ms) so cannot protect against abrupt loud noises like the firing of a gun and instead work better for loud sounds over sustained periods
Frequency
for sound, the number of times per second that a pattern of pressure changes or repeats (like wavelength- the smaller the wavelength the more cycles so higher the frequency) perceived as pitch measured in Hertz (Hz) 1 cycle per second is 1 Hz
categorical perception
for speech as well as other complex sounds and images, the phenomenon by which the discrimination of items is no better than the ability to label items listeners report hearing differences between sounds only when those differences would resutl in different labels for the sounds-- so the ability to discrimiante sounds can be predicted by how partipants label sounds
how can we look at formants to determine what speech sound is being made? what do the first two formants correspond to?
for vowels, the first two formants relate to how high or low the tongue is and how far forward or back the tongue is. just by looking at the first two formants we can tell what vowel sound is being made
How is frequency and tone height depicted on the musical helix? what about changes in tone chroma? how are octaves depicted?
frequency and tone height increase with the increasing heigh of the helix chroma changes in circular laps around the helix octaves are line dup on different levels
different locations in the cochlea help with ____ but not determining the ___ of a sound
frequency; not location
frequency is related to ____ frequency. Sounds are made up of ____ frequencies high frequencies correspond to ____ pitches low frequencies correspond to ___ pitches
fundamental frequency sounds are made up of many frequencies high frequencies-- high pitch low frequencies--- low pitch
why is it significant that gender gap in math and science is not universally seen in all countries?
gap is not intrinsic and may be cultural -- in some countries girls to better than boys so, it is helpful to see if gender/science stereotypes predict the gender gap
the the idea that pain is moderated in the spinal cord
gate control theory
how might we test haptic perception
get person to try to orient bars to be parallel with blindfold on -- test where things are located in space realtive to the body
in a study, people who spent more time off a relatively quiet island experienced ___ hearing loss
greater
these cells are analogous to the rods and cones of the eye but for the ear
hair cells
why is learning words difficult?
hard to figure out where one word ends and where another begins-- may just hear a stream of sound when you listen to a foreign language it is hard to pick out individual words
why is it harder to locate sounds when using headphones?
harder to localize sound if just listening through headphones because no head or body feedback-- no HRTF (head related transfer function)
when common objects that were easily to recognize visually were converted into a raised form, it was ____ for haptic search to determine what the objects were compared to vision. This is because vision relies more heavily on ____ shape and size
harder; geometric
applying pressure helps test ____
hardness
used to describe or characterize a common form of complex sound that is typically caused by a single vibrating source
harmonic spectrum
why do listeners still hear the pitch of the fundamental even if the fundamental frequency is removed?
harmonics overlap each other-- this overlap produces the strongest amplitude in the overall combined auditory signal at time interval corresponding to the fundamental frequency ex) harmonics will line up at every 4ms which correspond to 250 Hz-- this would be the fundamental for that collection of frequencies
How good are humans at determining where objects are in space?
have good time acuity can distinguish between the difference of 10 microseconds and 1 degree difference in space
why is looking at brain damaged patients useful for learning about speech in the brain?
have shown that there is hemispheric dominance for language-- the left side of the brain is more dominant for speech
what is critical for auditory localization? why?
having two ears for most positions in space, a sound source will be closer to one ear versus another-- pressure waves don't arrive at the ears at the same time-- sound will arrive at the ear closest to the source a bit faster also, the intensity of the sound is greater in the ear that is closer to the sound source
our acuity is best for which sense?
hearing
conductive hearing loss
hearing loss caused by problems with the middle ear bones-- lose ability to convey vibrations from the tympanic membrane to the oval window can occur when the middle ear fills with mucus during ear infections (otitis media) otosclerosis (causes by abnormal growth of the middle ear bones)
sensorineural hearing loss
hearing loss due to defects in the cochlea or auditory nerve happens most often when hair cells are injured can happen when certain drugs like antibiotics and cancer drugs are ototoxic meaning they kill hair cells directly
why does age impact hearing? what frequencies are impacted first?
hearing starts dropping in the 50s due to an accumulation of exposure to noises over one's lifetime--- even every day noises can cause hearing loss overtime - people from remote areas have been shown to have better hearing due to less accumulative exposure to sound related hearing loss impacts the higher frequencies first
how does frequency of sounds release in different parts of the cochlear partition being stimulated? what does this show us about the tuning of the cochlea?
higher frequencies lead to the area close to the oval window near the base of the cochlea being stimulated more lower frequencies leads to displacement of hair cells closer to the apex different places in the cochlea are "tuned" to different frequencies-- this tuning is called the place code for sound frequency
where do we have the highest acuity (like for two-point touch thresholds)?
highest spatial acuity on the fingertips, face, and toes on fingertips can resolve a separation between two stimuli of just 1 mm the wrist however is less sensitive
place of articulation for consonants
how airflow is obstructed: can be obstructed at the lips at the alveolar ridge (just behind the teeth) or at the soft palate
what is manner of articulation for consonants?
how much the airflow is being obstructed and the pattern of blocking 5 different variations
the challenge of articulation
humans are very good at perceiving speech however when speaking we anticipate the next sound and speech sounds will blend together-- there is an overlap between speech sounds-- this is called coarticulation
head cues (turning the head) for sound localization?
if the head is turned, the ITD/ILD will no longer be consistent with the location of the ITD/ILD when the head was at its initial location the location of the sound that is consistent when the head was still and after it was turned is considered to be the location of where the sound is coming from--- if the possible location of the sound doesn't change when the head is turned then stick with that location
what were the results of the police officer dilemma study when the picture was of a black person?
if the person was black: - slower to make a decision if they were unarmed - faster to shoot if armed when unarmed, blacks were mistakenly shot 16% of the time (compared to white who were mistakenly shot 12% of the time)
why was it important to note that the main effect for trust was the same for both races?
if you just looked at the means for trustworthiness- there was a lack of differences in perceived trustworthiness of black and white faces. white faces were rated as slightly more trust worthy but this trend was weak shows that an interaction was occurring-- hoping to find an interaction between implicit racial bias and trust (not just a main effect) an interaction is when the effect of one independent variable changes as a function of levels or values on another independent variable
when data was gathered from many countries and IAT tets were taken to assess attitudes about women and men and science and math, what was the result?
implicit (but not explicit bias) was shown to predictwhat math and science performance there was a strong positive correlation where more than a third of the actual performance differences was predicted by IAT tests-- shows that implicit biases have a strong effect
what were the findings from stanley et al study on implicit bias and trustworthiness
implicit bias as seen from IAT tests predicted trustworthiness-- the extent to which an individual trusts another person is related to the magnitude of that individuals implicit race bias individuals who's IAT scores reflected a stronger pro white implicit bias were more likely to judge white faces as being more trustworthy compared to black faces (and vice versa)
in the experiment were participants had to decide who to trust by giving money to a fictitious person, what were the results?
implicit bias impacts decisions on who to trust once again there was no main effect for white vs black faces and participants race did not predict trusting behavior implicit bias once again was a strong predictor in who to trust-- individuals who's IAT reflected a stronger pro-white implicit bias were more likely to offer more money to white partners compared to black partners explicit bias did predict trusting behavior (but only half as strong as implicit)
how are gender attitudes impacting math and science?
implicit gender attitudes are shown to predict gender differences in math and science achievement a lot of data suggests that there is a gender gap in interest and participation as well as performance in math and science between men and women ex) world-wide 8th grade boys were shown to perform better in math and science compared to girls
how does touch act like blurred vision?
in a situation where people had to read brail or when an image was blurred to match the visual acuity of the eye with the more limited acuity of touch on the fingertip of skin, similar mistakes were made:-- shows there is a common decision process for both haptic and visually perceived patterns But the main difference is that our tactile field of view is very narrow because we can only explore a small range of what our fingertip is in contact with
example of how pain can be moderated by chemicals?
in highly stressful situations may not feel pain until later-- pain blocked as a survival mechanism opiates can help moderate pain
where does neural transduction of sound occur?
in the organ of corti (in the cochlea)
where are touch receptors located. when are these receptors engaged?
in the skin both in the outer layer of skin (epidermis) and the underlying layer known as the dermis they are engaged whenever something makes contact with the skin
how is the connectivity of auditory information different than vision?
in the visual system, inputs from each visual field stay separate until they have each extended a fair distance in the visual cortex in contrast, auditory information reaches both sides of the brain only after a single synapse--- some of the projections that extended form the cochlear nuclei to the superior olive cross over to the opposite side of the brain
tactile agnosia
inability to identify objects by touch Caused by lesions to the parietal lobe (i.e., not a problem w/primary sensory area)-- problems can locate objects but cannot identify objects by touch
touch/tactile sensation
includes pressure, pain, and temperature like hot vs cold arises from different kinds of sensory receptors refers to all non-proprioceptive sensory signals from the body
on an equal-loudness curve, if you lower the frequency, you will have to ____ the actual intensity for a sound to sound the same as it is perceived
increase
how does the amplitude of the sound wave impact the movement of the tympanic membrane and oval window? what about firing rate?
increasing the amplitude results in a larger movement from the tympanic membrane and oval window the larger the amplitude the greater the firing rate of neurons
How does sensory information reach the brain?
initially, axons from various tactile receptors are combined into single nerve trunks-- however there are a number of somatosensory nerve trunks that arise in the hands, feet, arms, legs, and other areas of the skin also they have to carry the information a very far distance (can travel as far as 2 meters from skin to brain)-- to travel this far distance, information but travel through the spinal cord
this structure in hearing is analogous to that of the retina as it's job is to transmit sound into neural signals
inner ear-- cochlea
inner vs outer hair cells
inner hair cells are arranged in nearly straigh rows wiith shorter stereocilia in the form and longer ones behind - have more afferent fibers-- take information to the brain outer stereocilia form in rows that form the shape of a V or a W - have more efferent fibers-- convey information from the brain
inner hair cells have more _____ fibers and inner cells have more ____ fibers meaning that inner hair cells send information to the ____ and outer hair cells send information from the ____ so they are related in ____ down processing/
inner hair cells have more afferent fibers so they send information to the brain outer hair cells have more efferent hair fibers so they send information from the brain and are related more so to top-down processing
octave
interval between two tones in which the higher tone has twice the frequency of the lower tone (the interval between two sound frequencies has a 2:1 ratio)
why does the effectiveness of relative intensity decrease quickly as distances increases?
inver-square law-- when sound sources are close to the listener, a small difference in distance can produce a relatively large intensity difference listeners are better at determining differences between sound loudness within 1 meter of the head, but underestimate the distance to sound sources that are further away (the amount of underestimation is greater for larger distances)
As distance increases, sound intensity diminishes by ___ ___ ___
inverse square law
a sound that is 1 meter away can produce a relatively large intensity difference, however, for further distances, it would be harder to tell the difference for sound sources that are 39 meters and 40 meters away. why?
inverse-square law---A principle stating that as distance from a source increases, intensity decreases faster such that decrease in intensity is equal to the distance squared. This general law also applies to optics and other forms of energy.
How do we recognize the "d" sound in deem, doom, and dam as the same when it is different every time because of coarticulation?
lack of invariance in speech sounds-- despite acoustic variability in speech sounds people are able to map these sounds to few phonological categories.
Where are the vocal cords located?
larynx
list the exploratory procedures and what they are good for
lateral motion: texture pressure: hardness static contact: temperature unsupported holding: weight enclosure: global shape, volume contour following; global shape, exact shape
at what location in the brain does information from both ears arrive to help with the detection of interaural level difference (ILD)?
lateral superior olive (LSO)
where are neurons that are sensitive to differences in sound level from both era found?
lateral superior olive (LSO)
dissonant chords
less elegant ratios of note frequencies don't sound as pleasing -- unpleasant or jarring ex) 16:15 or 45:32
why can we see lightning before we hear it?
light travels way faster than sound
neurons in the medial superior olive (MSO) are like what neurons in vision and why?
like neurons for binocular vision-- they both require input early in life to develop properly ex) the ability to use ITDs depends on having experience with separate sounds coming from different places in space
why is it significant that the motor cortex is close to S1?
located right next to the motor cortex as it can help coordinate movement in response to touch the somatosensory and motor control systems are closely connected
timbre allows us to distinguish between sounds even if ___ and ___ are the same
loudness and pitch
what does 0 dB mean?
low amplitude, but no silence you can get negative decibels as well (similar to temperature Celsius scale
low-spontaneous fibers fire in response to ____ sounds while high-spontaneous fibers fire in response to ____ sounds
low- louder (think low louder) high- softer
high vs low spontaneous fiber and how they respond to sound intensity
low-- requires relatively intense sounds to fire high--- will fire in response to low levels of sound
articulation of vowels
made with relatively open vocal tracts vary mostly in how high or low or how forward of back the tongue is placed in the oral tract along also important if the lips are rounded or not
3 ossicles
malleus, incus, stapes
how is discriminating between faces and discerning depth perception similar to how we differentiate speech sounds ?
many small differences must be used together to make discriminations with enough experience, we can use the pattern of facial features to tell one face from another also we use multiple depth cues to determine what is the most likely depth of an object-- using a lot of integrated information similarly, we don't need acoustic invariant but instead need to be good at pattern recognition so we can distinguish between speech sounds-- we need to be as good at pattern recognition for sounds as we are for visual images our brains do a good job of integrating multiple sources of information into recognizable patterns
psychoacoustics uses ____ experiments to study frequency selectivity
masking
what portion of the auditory system is responsible for calculating ITDS?
medial superior olive (MSO)
where is the first place that information from both ears converges?
medial superior olive (MSO)
Twinkle twinkle little star is an example of a
melody
tensor tympani
middle ear muscle attached to the malleus-- tensing this muscle will decrease vibrations
Mask gets ____ effective as increase bandwidth, but only to a point: Critical bandwidth
more
when speech sounds become more clearly a part of language they are processed where?
more anteriorly in the left temporal lobe
does the medial geniculate nucleus have more efferent or afferent projections and where does it project to?
more efferent fibers Relays auditory signals to the temporal cortex Receives input from the auditory cortex
how is auditory processing very different from visual processing and why might this be?
most processing for hearing occurs before A1 while for vision, more processing occurs in the primary auditory cortex and beyond this could be because hearing is an older sense (why it uses older brain structures)
FA II or Pacinian corpuscle responds best to what (what are they most sensitive to)? what are they good at detecting/what is their primary function?
most sensetive to changes in skin deformation for frequencies at about 50-700 Hz detect high frequency vibrations and fine textures
these kinds of receptors pick up on changes in muscle length
muscle spindle (a kind of mechanoreceptor for Kinesthetic/proprioception
function of muscle spindle fibers
muscle spindle fibers measures the stretching of muscles or changes in muscle length which tells us proprioception
did participants race impact perceived trustworthiness? what about explicit bias?
neither the participants race nor their explicit bias predicted trustworthiness their implicit bias was the best predictor of how they would rate trustworthiness
what makes up the vocal tract?
network consisting of the larynx, pharynx, and the oral and nasal cavities
how are the belt area and parabelt area different from A1?
neurons in A1 respond to any sound while processing gradually gets more complex as sound travels through the auditory pathway-- sound processing becomes more complex so simple sine waves will elicit less activity in these areas further, the parabelt is better at cross-modal processing- combines sensory and auditory information
is pain and itching the same?
no have some receptors that respond to pain and itch, and some receptors that just respond to pain or just respond to itch in the spinal cord, pain neurons connect to itch inhibiting neurons the result that painful stimulation inhibits itch
is music uniquely human?
no--Certain birds can experience and enjoy music Snowball dances to "another one bites the dust" Not a rigid conditioned response (slowed down or sped up the music and he matched the tempo)
white noise
noise consisting of all audible frequencies in equal amounts (analogous to white light in vision in which all wavelengths are present)
like perceived loudness, pitch is related to but ____ perfectly correlated with the frequency of a sound
not
explain how obstruction of the ear canal leads to hearing loss
obstructing the ear canal prevents sound waves from traveling down the ear canal and influencing the tympanic membrane this can happen when wearing ear plugs or if excessive ear wax builds up in the ear
this is what it is called when the interval between two sound frequencies has a 2:1 ratio
octave
How can you tell what frequency an auditory nerve is specialized for?
of it fires even when the sound is played at a very low amplitude
humans can detect changes in sound by less than ____ dB
one
the vocal tract includes the ____ tract and the ____ tract
oral; nasal
is our perception of sound intensity experienced the same as the physical amplitude of a sound wave?
our experience of loudness doesn't increase directly with changes in amplitude (Steven's Power Law)-- we experience a larger physical change in comparison to the increase in decibels Relatively small dB correspond to larger physical changes ex) if something increases to be two times the amplitude, it doesn't mean it will be twice as loud an increase by just 6dB results in a doubling of pressure
Proprioception
our sense of body position in space
How do outer hari cells impact threshold tuning curves and inner hair cells sensetivity?
outer hair cells make up the part of the cochlear partition that is stiffer -- this makes the inner hair cells more sensitive to a narrow range of frequencies and allows for inner hair cells to respond more sharply
vibrations passed through the ossicles makes the ____ ____ move
oval window
forms the border between the middle ear and inner ear
oval window the stapes is attached to the oval window
the vestibular canal extends from the ___ ___ at the base of the cochlea to the ______ at the apex
oval window to the helicomtrema
how is the visual system similar to the hearing system when we consider the photoreceptors and the different AN fibers?
pattern of firing across all 3 cones is integrated by the visual system just as the pattern of the 14,000 AN fibers is integrated to determine sound frequency
when researchers manipulated sound stimuli to vary continuously from "bah" to "dah" to "gah" when did participants perceive changes in sounds?
people do not perceive the sounds as continuously varying -Also, "inside" the categorical boundaries, we have great difficulty distinguishing sounds - didn't distinguish between two "bahs" Instead, people perceive sharp categorical boundaries between the stimuli: ex) sounds sounded like Bah until they reached a bah-dah border (which only lasted for a very short time)-- then get an abrupt shift to dah even if there was the same acoustic change between two bahs and a bah and dah- the bah-dah shift will be heard because it is changing categories while the bah bah change is not perceived
why might explicit bias not be a good predictor of trustworthiness?
people may not explicitly endorse or be aware of their bias or, they may withhold from expressing their bias due to social desirability
for any given frequency increase, listeners will perceive a greater rise in pitch for _____ frequencies than they do for ____ frequencies
perceive a greater rise in pitch for lower frequencies than higher frequencies
nociception
perception of pain
ANs often fire at one distinct point in the period (cycle) of a sound wave (at given frequency)
phase locking
The process through which vocal folds/cords vibrate when air pushes out of the lungs. when air passes through the vocal cords at the larynx
phonation
sounds of speech
phonemes Any given language only uses a given fraction of speech sounds (20-35 speech sounds)
what makes up the outer ear?
pinna and auditory canal (ear canal)
this psychological aspect of sound is related to frequency as important for music
pitch
isointensity curves plot the ____ ____ of an auditory nerve against varying frequencies at varying _____
plots the firing rate of an auditory nerve at varying frequencies at various intensities
how is the attack different for when a violin string is plucked versus bowed?
plucking has a sharp/abrupt onset and then get a sharp fall-off (short attack and longer decay phase) Using a bow has a gradually increase in amplitude and a slower decline
how sound is specifically transmitted in the inner ear
pressure waves in the vestibular canal are transmitted to the middle canal middle canal vibrations move the cochlear partition up and down this moves the tectorial membrane back and forth movement of the tectorial membrane causes the stereocilia on the ends of hair cells to bend -- this causes neurotransmitters to be released -- neural signals from the hair cells are carried to the brain by the auditory nerve
source segregation (auditory scene analysis)
processing an auditory scene consisting of multiple sound sources into separate sound images
in general, musical instruments produce notes below how many hurts? why does this matter/what are the implications?
produce noted below 4000 Hz With higher notes, listeners have great difficulty perceiving important relationships between tones-- may have a harder time perceiving octaves
ototoxic
producing adverse effects on cochlear or vestibular organs or nerves certain antibiotics and cancer drugs can directly kill hair cells-- leads to sensorineural hearing loss
what is it called when an AN 's firing rate is maxed out and why does this happen?
rate saturation this happens because the stereocilia are pivoting as much as they can -- increasing the tone therefore has no additional effect on the AN fiber's firing rate
what does an intensity function graph (what is the x and y axis) and how can you tell which ANs are low of high frequency?
rate-intensity function graphs the intensity of the sound (dB) on the x-axis and the firing rate on the y-axis you can tell which ANs are low because they won't begin to fire as strongly until the intensity increases compared to high intensity ANs that will begin responding more even at smaller intestines
size of the receptor field
receptors are activated wehn stimulation is applied to a certain region of the body-- some receptive fields are larger than others and some are very small the size of the receptive field is the extent to which a given receptor will elicit a response
type of stimulation
receptors respond to different stimulus events like pressure, vibration, or temperature changes
what is the secondary pain effect?
reflects the influence of cognition on pain the emotional response associated with long term suffering that occurs when painful events are imagined or remembered -- imagining the pain is associated with the prefrontal cortex
simplest cue for determining the distance of sound?
relative intensity of sound
relative intensity is analogous to what in vision?
relative size--- we generally know how large certain objects are for relative intensity in hearing-- we generally know how loud certain sounds are
why is it important to note that amplitude is measured in dB and how does this relate to our hearing?
relatively small decibel changes can result in large physical changes for example, an increase by just 6dB results in a doubling of pressure
formants
resonance of the vocal tract; a frequency area of acoustic energy in vowels and other resonant sounds formants are specified by their center frequency and are denoted by integers a=that increase with relative frequency
Initiates speech--Diaphragm pushes air out of lungs, through trachea, up to larynx
respiration
SA II or Ruffini endings responds best to what (what are they most sensitive to)? what are they good at detecting/what is their primary function?
respond to sustained downward pressure (low sensitivity to vibrations across frequencies) and lateral skin stretch detect finger position
in a cueing task, people responded faster for____ cues compared to ___ cues - these results consistent with analogous experiments conducted in purely visual domain. why does this matter?
responded faster to valid cues vs invalid cues So...can indeed "deploy" spatial attention w/in tactile sense
Tinnitis
ringing in the ears caused by damage to hair cells
hw many speech sounds?
roughly 850
for phase locking, the neurons doesn't have to fire on every cycle but each firing will occur at the ___ point in the cycle
same
phantom limb
sensation perceived from a physically amputated limb of the body
what two things do outer hair cells help with? what would happen if we didn't have outer hair cells?
sensitivity and frequency selectivity without outer hair cells a higher intensity tone would be required to excite an AN fiber and the fiber would be less selective in frequencies to which is would fire
sensitivity vs acuity
sensitivity= what is the lowest level of stimulation we can perceive acuity= how high definition (how well can we tell the difference between two stimuli) - what's the smallest difference we can detect between two stimuli (when can we tell they are different and not the same)
what is the most common form of hearing loss?
sensorineural hearing loss--- but specifically caused by aging
nociceptors respond to what? why is this important?
sensory receptors that respond to painful input such as extreme heat or pressure they are important because they help us sense danger/when potential damage may be done-- if we didn't have the perception of pain we couldn't tell when something was wrong
Ultimately, pain experience determined both by ____ nature of painful stimulation AND ___/___ emotional response to it
sensory; emotional; cognitive
in S1, projections form area 3 to area 2, largely concern what?
shape and size
why is the egocenter for touch different?
shifts between relevant locations can even shift beyond the body when we use tools like driving a car -- feeling the road
what do equal-loudness curves show us?
show us where frequency and sound levels will be experienced for what they physically are ex) something at 0.1 hertz will be experienced as 10dB even if it is really 40dB
what is the police officer dilemma study? what was measured?
shows participants pictures of white or black people either holding a gun or phone and the participant has to decide to shoot or not the study recorded accuracy and response time
when looking at an audibility threshold what does it show us about what frequencies we are more sensitive to?
shows that we are much more sensitive to high frequencies compared to low frequencies meaning that in order to pick up low frequencies we have to increase the intensity (dB)
inner hair cells a lined in ____ file and provide most of their info to the ___ via ___ ___ fibers
single file; brain; auditory nerve (AN)
stereocilia
small hairlike projections on the tops of inner and outer hair cells when flexed they initiate the release of neurotransmitters
what does the rat pup experiment show us about the importance of social touch? how were pups with greater maternal care different?
social touch is critical for development maternal licking and grooming behavior is inherited by the caregiver whether or no the pup was genetically related or not shows epigenetic effects §Pups that were licked and groomed tend to be more bold, confident than those that weren't
from the thalamus, where does sensory information travel first?
somatosensory area 1 (S1)--- the primary reciving area for touch in the cortex
evidence that both visual and auditory information becomes combined when we perceive speech
some speech areas become active when lip reading previously deaf individuals exhibit increased activity in the visual cortex when perceiving speech (they had gotten good at reading lips when deaf)
what is a pure tone?
sound containing just one frequency these are sine waves pure tones are not common in the real world-- sounds are generally a combination of many frequencies
how is the way sound travels different from light?
sound needs a medium to travel through to reach us while light doesn't
sound waves travel at different speeds based on the medium they pass through. Do sound waves travel faster through water or air?
sound travels faster through water: air: 340 meters/second water: 1500 meters/second
what happens as sound spreads out from an area
sound waves will decrease in amplitude over greater distances (why you can't hear things at far distances)
spatial segregation of sound
sounds that arise from the same space are treated as emanating from the same source also, sounds that are perceived to move are more easily recognized as separate from background noise
spectral segregation of sound
sounds with the same pitch or similar pitches are more likely to be treated as coming from the same source
How does the auditory system sort out sounds in a busy environment with many sounds?
source segregation aka auditory scene analysis
Certain sounds (making words) are more likely to occur together and babies are sensitive to those probabilities- this is called _____ learning
statistical
the stiffer region of the cochlea is impacted by ____ frequencies while the more flexible region is impacted by ____ frequencies
stiffer-- higher flexible-- lower
what effects the pitch of sounds in terms of the vocal cords?
stiffness and mass of vocal cords impacts the pitch as vocal cords become stiffer vibrate faster as tension increases creating sounds with higher pitch
mechanisms of gate control theory
substantia gelatinosa is a jelly-like region of interconnecting neurons in the dorsal horn of the spinal cord that -- nociceptors arrive at the dorsal horn of the spinal cord in the outermost layers called the substantia gelatinosa--- neurons there receive info from the brain substantia gelatinosa is the "way station for pain signals" inhibitory neurons receive information from the large diameter A-beta fibers coming from the skin information from pain centers in the brain determine can be sent to the SG and the SG receives excitatory and inhibotry signals from nociceptors
where do inputs form both ears converge?
superior olive
when there is a hesitation (just a little in front of behind where the central pattern would be) this is called _____
syncopation
the ___ membrane is what bends the hair cells
tectorial
the shearing motion of the ____ membrane causes the _____ of both inner and outer hair cells to ____ back and forth causing the release of ____
tectorial; stereocilia; bend; neurotransmitters
why is the study on trust and racial implicit bias important?
tells us about trust and decision making and that our implicit biases can have a strong impact on our attitudes and perceptions of others as well as our behavior. the decision that we may think are concsiouly made might actually be implicitly determined and it is important to be aware or implicit biases and how they can have real life consequences when it comes to decision we make and costs that may come to certain people in society
the existence of phase locking means that the firing pattern of an AN fiber carries a ___ code for the sound frequency
temporal fo example, is the AN fiber carries and action potential of 100x a second then downstream neurons listen to the AN fiber can infer that the sound wave includes a frequency component of 100 HZ
FA I or Meissner corpuscle responds best to what (what are they most sensitive to)? what are they good at detecting/what is their primary function?
temporal changes in skin deformation (about 5 to 50Hz) and skin slip detect low frequency vibrations and are responsible for a stable grasp
why is it that detecting frequencies above 5000Hz is not too good?
temporal coding doesn't contribute to the perception of pitch -- pitch perception becomes way worse because only place coding can be used
muscles in the middle ear
tensor tympani and stapedius
in S1, projections form area 3 to area 1 largely concern what?
texture
how does the range of hearing differ for young verses older people?
the 20-20000 Hz range is for the younger populations-- by the time most people reach college they may have lost their ability to hear frequencies above 15000Hz ability to hear higher frequencies decreases throughout life-- the highest audible frequency become lower and lower overtime
articulation
the act of manner of producing a speech sound using the vocal tract
vocal tract
the airway above the larynx used for the production of speech includes the oral tract and the nasal tract
why might you feel like your amputated arm is there if touched on a certain spot on your face? phantom limb
the area being touched on the face or the remaining limb is represented in the somatosensory cortex as residing between the hand and the arm (which had been amputated)-- when the arm is removed, the neurons that once responded to the arm move to areas that respond to touch in the face or in the remaining limb but because parts of the brain "listening" to the hand and the arm are not fully aware of the switch/altered connections- by stimulating the area on the face, people may feel as though their limb is still there
other than the cochlea, what else is tuned?
the auditory nerve-- different nerve fibers respond to different sound frequencies
what is the point of having different AN fibers with different spontaneous firing rates?
the auditory system can determine the frequency of incoming sound waves by integrating information across many AN fibers and using the "pattern" of firing to determine the sound frequency
at what frequencies are the ILD and ITD the most different? why does this matter?
the biggest difference is for frequencies above 1,000 HZ at which point the head creates a shadow there isn't much ILD for lower frequencies SO, ITDs are better and more reliable but ILDs can help determine the angle a sound is coming from with the help of ITDs
how does reliably discerning the spectral characteristics of sound depend on context?
the brain may interpret spectral tilt as being a result of something in the environment (like hard or soft surfaces) and so the second peak frequency would then be used to interpret the sound. But if there always seems to be energy around the second peak, then listeners will only use tilt
egocenter
the center of a reference frame used to represent locations relative to the body
good continuation for sound and restoration
the continuous auditory stream is heard to continue behind the masking sound restoration is when the auditory system restores the portion of the continuous stream that was blocked out by the interrupting sound
frame of refernece
the coordinate system used to define locations in space
the point at which the mask doesn't become more effective is called
the critical bandwidth- Critical bandwidth describes frequency range within a particular frequency detection "channel"
Interaural level difference (ILD)
the difference in level (intensity) between a sound arriving at one ear versus the other
interaural time difference (ITD)
the difference in time between a sound arriving at one ear versus the other measured in microseconds
how does the level of bending of the stereocilia impact firing rate?
the farther teh stereocilia are bended, the faster the AN fibers linked to the hair cells fire
if it takes a higher-intensity tone to excite an auditory nerve fiber (AN) then what does this tell us?
the fiber is less selective to that particular frequency
what does it mean when we say that the existence of phase locking means that the firing pattern of an AN fiber carries a temporal code?
the firing pattern of the neuron itself (over time) varies regularly, conveying info about sound frequency fo example, is the AN fiber carries and action potential of 100x a second then downstream neurons listen to the AN fiber can infer that the sound wave includes a frequency component of 100 HZ
primary auditory cortex (A1)
the first area within the temporal lobes of the brain responsible for processing acoustic information neurons from A1 project to the surrounding Belt area
cochlear nucleus
the first brain stem nucleus at which afferent auditory nerve fibers synapse
oval window
the flexible opening to the cochlea through which the stapes transmits vibration to the fluid inside
when tilt was kept the same for both sentences in a study looking at vowel sound interpretation, what did listeners use to identify the vowel sound? what if the second peak stayed - what did listeners rely on then?
the frequency of second peak only when second peak was present, they relied on tilt
characteristic frequency (CF)
the frequency to which a particular auditory nerve fiber is most sensitive
volley principle
the idea that multiple neurons can provide a temporal code for frequency if each neuron fires at a distinct point in the period of a sound wave but does not fire on every period
fundamental frequency
the lowest frequency component of a complex periodic sound
what is the fundamental frequency?
the lowest frequency component of a complex periodic sound
audibility threshold
the lowest sound pressure level that can be reliably detected at a given frequency
amplitude or intensity of sound waves
the magnitude of displacement (increase or decrease) of sound pressure wave (size up and down from peak to trough of a sound wave) Amplitude is perceived as loudness measured in Decibel (Db) Goes up Logarithmically
two-point touch threshold
the minimum distance at which two stimuli are just perceptible as separate
medial geniculate nucleus
the part of the thalamus that relays auditory signals to the temporal cortex and receives input from the auditory cortex the last stop in the auditory pathway before the cerebral cortex Relays auditory signals to the temporal cortex Receives input from the auditory cortex has more efferent than afferent fibers meaning more projections are coming form the cortex to the MGN than going to the cortex from the MGN
what is rhythm? why is it important for music?
the pattern of beats and intervals between them people are predisposed to grouping sounds into rhythmic patterns sounds that are louder and higher in pitch are perceived to be leading their groups timing relationships between one sound and another helps determine the accent
how are formants important for distinguishing speech sounds?
the peaks of the speech spectrum are called formants and these represent where energy is concentrated at different frequencies depending on the length of the vocal tract (for smaller vocal tracts like in children, formants are at higher frequencies than in adults with longer vocal tracts)-- listeners use the realtionships between formant peaks to perceive speech sounds-- can use the energy in the region of the lowest three formants to distinguish almost all speech sounds
tempo
the perceived speed of the presentation of sounds
gestalt principles for sound segregation (auditory stream segragation)
the perceptual organization of complex acoustic signal into separate auditory events for which each stream is heard as a separate event sounds that are similar to each other tend to be grouped together into streams (gestalt principle of similarity)
coarticulation
the phenomenon in speech whereby attributes of successive speech units overlap in articulatory or acoustic patterns
how can context change the spectral shape and thus the timbre or two sounds?
the physical environment can change the timbre higher frequencies are reinforced by harder surfaces (tile floor and concrete walls) and dampened by softer surfaces (like carpet)
rate saturation
the point at which a nerve fiber is firing as rapidly as possible and further stimulation is incapable of increasing the firing rate
what determines the width of the critical bandwidth?
the point at which further widening has no effect on detecting the tone defines the critical bandwidth
somatosensory area 1 (S1)
the primary receiving area for touch in the cortex located in the parietal lobe broken up into three different areas analgous to V1 (vision) and A1 (hearing)
temporal integration
the process by which a sound at a constant level is perceived as being louder when it is of greater duration the term also applies to perceived brightness in terms of light
define phonation
the process through which vocal folds are made to vibrate when air pushes out of the lungs
temporal segregation
the process whereby sounds that are linked in time are grouped together, whereas sounds that are not correlated with one another are not grouped together sounds that start (attack) and end (decay) at the same time are likely to be grouped together as coming from the same source
what is timbre?
the quality of sound or feel of the sound instruments that play the same note have a different quality of sound-- a guitar playing a C doesn't sound like a trumpet playing a C-- they have different feels of timbre allows us to distinguish between sounds even if pitch and loudness stay the same
critical bandwidth
the range of frequencies conveyed within a channel in the auditory system
relative intensity
the ratio of the intensity of a given sound wave to the intensity at the threshold of hearing we know that sounds become less intense at greater distances (requires making assumptions about the sound source)
dorsal column-medial lemniscal pathway (DCML pathway)
the route from the spinal cord to the brain that carries signals from the skin, muscle, tendons, and joints helps with movement
somatosensory area 2 (S2)
the secondary receiving area for touch in the cortex (seems to be more important for the teeth, gum, and jaws and intrabdominal organs)
what is spectral shape and why is it important?
the shape of the spectrum that helps us distinguish between different sounds even if the fundamental frequency and harmonics are the same, the shape of the spectra varies
how does bending of the tip link of stereocilia lead to depolarization and the release of neurotransmitters?
the shearing motion of the tectorial membrane against stereocilia leads to tip links pulling on taller stereocilium in a way that opens an ion pore kind of like opening a gate-- this action causes ions to rapidly flow into the hair cells which leads to depolarization. depolarization leads to calcium entering the cell and initiation of the release of neurotransmitters form the base of the hair cell which will stimulate the dendrites of the auditory nerve
spectral composition of sounds
the sound qualities of air dampen high frequencies more than low frequencies so when sound frequencies are far away high frequencies decrease in energy more as the sound travels from the source to the ear (muffled effect)
harmonic spectrum
the spectrum of a complex sound in which energy is at integer multiples of the fundamental frequency
harmonic spectrum
the spectrum of a complex sound in which energy is at integer multiples of the fundamental frequency: typically caused by a single vibrating source like a guitar string, saxophone reed or human voice an important component of the harmonic spectrum ist eh fundamental frequency
cochlea
the spiral cavity of the inner ear containing the organ of Corti, which produces nerve impulses in response to sound vibrations.
kinesthesis
the system for sensing the position and movement of individual body parts in space
why does discrimination ability decrease at higher pitches?
the temporal code for frequencies starts breaking down at above 1000 HZ and is relatively nonfunctional above 5000 Hz (auditory system suffers because it has to depend on place coding alone)
why is the temporal code more accurate for lower frequencies and when doe sit become inconsistent? why?
the temporal coding is more accurate for lower frequencies and becomes inconsistent at frequencies that are higher than 1000 HZ (is virtually absent above 4000 or 5000 HZ) the inconsistency is due to the refractory period of the AN fiber-- for higher frequencies, AN fibers can't produce action potentials quickly enough to fire on every cycle of the sound
how does the pinnae torso help with sound localization?
the unique shape of pinnae funnels some sound frequencies better than others. Listeners learn how they hear sound from, different places in the environment the pinnae will reduce and boost certain frequencies at it is not symmetrical front to back-- this helps listners determine where a sound is coming from
why is voicing important for articulation of consonants?
the vocal cords may be vibrating a lot or not vibrating (vibrating very very little) vibrating= voiced consonants (can be felt if you put a finger on the throat) not vibrating= voiceless consonants
because the higher the frequency, the harder it is for temporal coding, what helps with this issue?
the volley principle--- multiple neurons can provide a temporal code for even high frequencies if each neuron fires at a distinct point in a period of a sound wave--- one might fire at the beginning and one at the end of the phase, etc.
how are the touch receptors analogous to rods and cones
there are 4 primary types of touch receptors and they are specialized to respond to different variations in 1. Type of stimulation to which the receptor responds 2. Size of the receptive field 3. Rate of adaptation (fast versus slow)
what is the rate of adaption. what is slow vs fast adaption and why does it make a difference?
there are fast adapting receptors and slow adapting receptors that respond differently based on how a stimulus is applied fast adaption: these receptors will respond with short bursts of APs- first when the stimulus is applied and then when the stimulus is removed again - they won't respond if something is "steady state"- if you are in contact with an object for a long time slow adapting receptors remain active throughout the time in which the stimulus is in contact with the receptive field-- so if you are holding an object for a long period of time
these kind of receptors located in the epidermal and dermal layers of skin inform us about changes in skin temperature
thermoreceptors
function of the middle ear muscles-- the tensor tympani and stapedius
these muscles tense when sounds are too loud--- acoustic reflex they restrict movement of the ossicles and muffle pressure changes that may be large enough to damage the inner ear
why is it that, a 200Hz tone presented at 70dB sounds about as loud as a 900Hz tone presented at 60dB?
they both fall on the same equal-loudness curve even if tones of different frequencies have different physical intensities they can sound equally loud to each other if they fall on the same curve
why do children have higher pitch voices? how do the pitches of adult male voices differ from children and adult females?
they have smaller vocal folds (cords) compared to adults during puberty, testosterone increases the mass of the vocal folds leading to lower-pitch voices
why are low-spontaneous fibers more like cones? tradeoffs?
they require more energy to start responding (respond to more intense sounds) but retain their frequency selectivity over a wider range of intensities cones also require more energy to work and they are more sensitive to changes in light
when you are walking away from a football game, the announcer seems to become muffled as you move further away. why is this?
this has to do with the spectral composition of sounds--- higher frequency sounds decrease in energy more with distance compared to lower frequencies-- leads to a muffled effect the further you are from a sound the more muffled it sounds this is why thunder at a further distance sounds more like a boom than a crack
this is the reason that the loudness of sounds depends on duration. Within limits, longer sounds are heard as longer
this is because the summation of energy over a brief but noticeable time determines our perception of loudness--a process called temporal integration
where else do we see contrasts being important for perception other than just for speech?
this is similar to how we perceive melodies or brightness in vision-- perception in this case is defined by changes between adjacent notes and not by exact notes in particular- contrasts also play a large role in how we perceive color, size, as well as line orientation
the ____ of vocal cords leads to a higher pitch sound
tightening
to interpret vowels, listeners use both spectral ___ and the frequencies of spectral ___ to identify vowels
tilt; peaks
the perceptual quality that differs between instruments and vowel sounds in language is an example of
timbre
despite have the same loudness and pitch, we still are able to detect the psychological difference in sensation/quality caused by different complex sounds. This is called _____ and it is caused by harmonics and other ____ frequencies that are above the _____ frequency and that are also produced by many single vibrating sources
timbre caused by harmonics and other higher frequencies that are above the fundamental frequency
how can we distinguish between two sounds using timbre
timbre is effected by the sounds context: - two sounds may share the same fundamental, however the spectra of the two sounds overlap may be different-- some harmonic frequencies may be emphasized more than others sounds are different because they have different spectral shapes
respiration for the production of speech?
to initiate speech sounds, air must be pushed out of the lungs through the trachea and up to the larynx this is achieved when the diaphragm flexes to draw air into the lungs and elastic recoil forces air back up towards the larynx
how does masking along with the critical bandwidth work to impact the detection of different fequencies?
to measure the width of the critical bandwidth, subjects listen for a tone in the center of a band of noise of constant intensity (white noise)-- it is harder to detect the noise as the band noise widens up to a point-- eventually, further widening had no effect on detecting the tone (this point determines the critical badnwidth)
when would we expect the ITD to be low?
when a sound is coming from straight behind or straight in front (ITD in this case would be 0 microseconds for right in front 0 microseconds right behind- the azimuth would be 0 degrees and 180 degrees)
how is timbre used to group sounds?
tones that deviate from the rising and falling frequencies are heard to pop out of a sequence individual tones pop out if they don't match the rising and falling pattern of other tones sounds that share the same timbre are grouped together grouping with timbre is robust because sounds with similar timbres usually are coming from the same sound source---helps disambiguate otherwise confusing combinations (cf. "good continuation"-- can tell difference between a saxophone and a voice at the same frequency
true or false: the process of perceiving sound is biased towards hearing rhythm
true
true or false: we don't usually experience the actually physical intensity of a sound the same as it is psychologically experienced
true
true or false: implicit bias impacts actual trusting behavior
true-- IAT predicted behavior in a "trust game"
true or false: people are really good at learning new sounds and recognizing them?
true-- people are good at recognizing completely new sounds even if they only heard the sound a few times listeners only needed a few repetitions to perform above chance at recognizing and segregating a novel sound from background noise even
true of false: equal-amplitude sounds can be perceived as louder or softer than each other based on the frequencies of the sound wave
true-- there is an inequality between sound pressure and loudness (perceived amplitude) ex) a 200Hz tone presented at 70dB sounds about as loud as a 900Hz tone presented at 60dB because they both fall on the same equal-loudness curve
Axons of various tactile receptors combine into single nerve ____. axons enter the ___ horn of the spinal cord
trunks; dorsal
why was trust used to measure implicit race attitudes in the study by Stanley et al?
trust is strongly related to how positively or negatively we judge others and is influenced by many perceived qualities like ability, honesty, reliability, etc. also, trust can strongly influence decision making and behaviors ex) in job hirings/promotions, friendships, justice system, etc.
Place Code (for sound frequency)
tuning of different parts of the cochlea to different frequencies in which information about the frequency of a given sound coming in is coded by the place along the cochlear partition that has the greatest mechanical displacement the basilar membrane is thickest at the base and becomes thinner as it widens out towards the apex- higher frequencies impact the narrower and thicker regions towards the base and lower frequencies impact the thinner, wider regions towards the apex
when a second tone of a slightly different frequency is added and the rate of for the firing of the first tone actually decreases
two-tone suppression
what serves as the border between the outer and middle ear
tympanic membrane
order of connections for the middle ear bones
tympanic membrane--malleus--incus--stapes--oval window (of the cochlea)
How do humans recognize sounds despite coarticulation?
use categorical perception •major factor in our ability to recognize "same" sound given coarticulation
How is frequency encoded in the cochlea?
uses temporal codes or place codes this is possible due to the physical properties of the basilar membrane which changes in thickness along the length of the cochlea - high frequencies are displaced more towards the base - low frequencies are displaces more towards the tip (or the apex)
what is perception for action
using somatosensation to help us grasp/manipulate objects, maintain balance, etc.
when airflow is obstructed at the soft palate what sounds are made?
velar speech sounds: g, k, ng
How do vibrations cause sound?
vibrations cause molecules in the object's surrounding medium to vibrate as well, causes pressure changes (waves) in the medium
what is voicing?
vocal fold vibration during production of sounds
location of articulation
vocal tract
voicing: vibrating
voiced consonants (can be felt if you put a finger on the throat) sounds; b, m, z, l, r
voicing: not vibrating
voiceless consonants: p, s, ch
even if one neuron cannot fire in response to every cycle of a higher-frequency, multiple AN fibers together can provide a temporal code for frequency if multiple neurons each fire at different periods in the sine wave.
volley principle
what did stanley et al test for using Implicit Association Test (IAT)?
wanted to see if implicit racial bias predicted trustworthiness ratings: first had subjects take an IAT test-- had subjects associate good and bad qualities with members of various groups (white or black)
why is implicit bias harder to change?
we aren't conscious of our implicit bias
co-occurrence in speech
we learn what features in speech tend to co-occur in our native language -- this is why it is often difficult to percieve and produce new pseech sounds from a second language dollwoing experince with a first language infants also use co-occurrence to learn words
why is rhythm in a large part psychological? examples?
we might hear rhythms when they don't actually exist In voices- people have own characteristics rhythms in the way that they talk Rhythms are intrinsic Heart Rhythms: bad sign if you have a very regular heart rate Complex system-- want it to be able to correct itself Too regular than too rigid May imagine rhythm to be there even if it isn't there: Daily life examples like in the car, train, etc.
how does direct and reverberant energy act as a distance cue?
when a sound source is clear, this means that the energy that is reaching the ear is rather direct--- reverberant energy is (which is bounced off of surfaces in the environment) increases with distance
when looking at a spectrum of sound coming from the vocal folds we can see a _____ spectrum. After passing through the ___ tract, which has a resonance based on the vocal tract ___, we see peaks or ____ and troughs of energy at different ____ in sounds that come out of the mouth
when looking at a spectrum of sound coming from the vocal folds we can see a harmonic spectrum. After passing through the vocal tract, which has a resonance based on the vocal tract shape, we see peaks or formants and troughs of energy at different frequencies in sounds that come out of the mouth
how does good continuation/restoration appear in the brain?
when looking at the brain: Further experiments show that many "restored" sounds are reflected in brain activity as if present-- it is as if the sound is really there (even though it is missing)
when was the greatest cost for an invalid cue and why did this matter? what does it show?
when observers expected a tactile cue but recieved an auditory or visual stimulus instead there was the largest spatial cueing effect this implies that the sense of touch may have a restricted attentional channel that is harder to reshifted away from to focus on a different kind of stimulation or vision and hearing are connected in someway because our attention is directed out into space while for touch our attention is directed towards our own body shows that it is hard to reshift attention when cued to focus on something tactile
the placebo effect and pain
when people think they are taking an analgesic drug they experience less pain (but actually are not)-- placebos actually inhibit nociceptive processing in the spinal cord
when is ITD the largest?
when sound comes directly from the left of directly from the right left: -90 degrees; -640 microseconds right: 90 degrees, 640 microseconds
when does frequency selectivity work the best?
when sounds are faint (worsens with louder sounds)
when it came to making errors in the police dilemma game, how did mistakes differ for race when the target armed but not shot?
when target was armed but not shot: Whites were not shot 12% of the time blacks were not shot 7% of the time shows that blacks were shot more often
when it came to making errors in the police dilemma game, how did mistakes differ for race when the target was unarmed but shot anway?
when target was unarmed but shot anyway: white: shot 12 % of the time black: shot 16% of the time blacks were shot when unarmed at a greater rate
How did McGruk and McDonald show that what someone sees can impact what they hear?
when the sound "bah" was played and participants were shown a person making the sound "gah" on a screen they perceived the sound "dah" which is an intermediate between bah and gah
when would it be beneficial to a have a slow adaption rate?
when you are in contact with an object for a long period of time-- like if you were holding an object
what is the trade-off for high-spontaneous fibers?
while they respond to low levels of sound, they can easily become saturated so frequency selectivity is poor when intensity level is high
stereotypes
widely held beliefs that people have certain characteristics because of their membership in a particular group ex) race, gender, political affiliation, attractiveness
as you increase the bandwidth in a masking experiment what must happen to detect the target sound?
would have to increase the intensity to hear the sound as the bandwidth increases (at least until a certain point- critical bandwidth)
how to interpret the equal-loudness curve (look at graph)
x-axis is frequency y-axis is the sound level (dB)-- the actual physical sound level (amplitude) numbers in the middle are what the sound will be experienced as perceptually
are humans good at determining small changes in frequency?
yes-- can distinguish between 999 and 1000Hz (can determine a difference of only 1/10 of a percent)
how is locating a sound different from how we locate objects using vision?
you could tell where the owl was based on what side of the fovea the retinal image falls on but for hearing, sound is entering both of the ears regardless of where the owl is -- we don't have the same topographical mapping on the retina that we do for hearing-- sounds at different locations don't land on different locations on the cochlea
how is the somatotopic mapping analogous to sight?
§Analogous to retinotopic mapping found in vision §Adjacent areas on skin (mostly) connect to adjacent areas in brain
sensitivity to vibration?
§Most acute around 200-300 Hz we are not equally sensitive to all frequencies
what is the limit to how fast individual ANs fire, and hence to reliability of temporal coding (TC)?
§TC OK up to around 1000 Hz §Above 1000 Hz, gets inconsistent §Above 4-5 kHz, doesn't work at all. BUT: the volley principle can help for high frequencies
Reissner's membrane
§Thin sheath of tissue separating the vestibular and middle canals
acuity for touch, vision, and audition using the two-point threshold study that administered two pulses?
§Touch: Sensitive to time differences of only 5 ms §Vision: Sensitive to time differences of 25 ms Audition: Sensitive to time differences of 0.01 ms
•How good is our sensitivity to deflection? (e.g., raised dots)
§Very acute—c. 1 micrometer (millionth of a meter)
how is amplitude encoded in the cochlea?
•Amplitude/intensity: relatively simple Louder sounds displace cochlear partition more, creating stronger movement of tectorial membrane This causes faster hair cell firing rates (analogous to brightness coding in vision)
as sounds become more complex where are they processed?
•As sounds become more complex, processed by more anterior and ventral regions of superior temporal cortex-- further away from A1
what subunits is music organized into?
•Music is organized into subunits defined by time: - signatures (e.g., 3/4, 4/4) - measures - and then larger units (e.g., verse, chorus) Organized by "beat"/rhythm
rate inensity function
•Plots firing rate of an AN to a sound of constant frequency at increasing intensities
