Midterm 1 Flashcards
What is phenomenology?
focuses on the expereince of stimulus
person expereinces stimulus than describes it
What are some cons of phenomenology?
poor control over the stimulus, cannot easily repeat observations, relies on introspective reports
What role does phenomenology have?
useful if followed up by systematic controlled expereiments to verify
What is psychophysics?
The study of the relationship between the physical stimulus
and our perception of that stimulus
Who developed the original set of psychophysical methods?
Gustav Fechner
What is the absolute threshold?
smallest amount of energy needed to
detect a stimulus
What would a graph of the idealized absolute thershold look like?
no one would notice a stimulus and then once the threshold is reached everyone would detect it
What is the method of adjustment?
psychophysics
The observer ‘adjusts’ the stimulus intensity until the stimulus is
detectable
What is a pro and a con of the method of adustment?
PRO: fast and easy for observer to perform
CON: open to bias, more variable than other methods
What is the method of limits?
uses ascending and descending series, alternates between gradually increasing or decreasing the intensity of a stimulus until a participant can just detect it
What is the simple staircase procedure (method limits)?
trials begin above/below threshold, continues to increase/decrease stimulus until observer changes answer, direction is reversed, and so on
What is an interleaved staircase procedure?
two staircases at the same time, one starts high the other starts low
What is the method of constant stimuli?
uses range of values that brakcet threshold presented in a random order
What is the point of subjective equality?
PSE (50%)
intensity at which you cannot differentiate between the stimulus
and noise, or when you cannot tell the
difference between two stimuli
What does a steep slope on a psychometric function mean?
high precision (low variability)
What is the purpose of signal detection theory?
used to
assess thresholds independently of the response criteria
What are the 4 responses in signal detection theory?
hit (correct), miss (no when stimulus), false alarm, correct rejection
In signal detection theory every trial is (equation)?
signal + noise (S+N)
What does liberal criterion look like on the distribution?
N results in high probability of false alarms, S+N result in high hits
What does conservative criterion look like on the distroibution?
N presents few false alarms, S+N results in low hits
A persons sensitivty is indicated by what on probability distribution?
the distance (d’) between the peaks of N and S+N distributions
How can we use signal detection theory experimentally?
measure the ROC curve by manipulating the reward/cost of
hits and false alarms
measure hits and false alarm rates assuming a neutral
criterion. This provides one point on the ROC curve, a
mathematical formula can be used to compute
What is another name for difference threshold?
DL (differece limen), just noticable difference (JND)
What is Weber’s Law?
JND/S = K
K is a constant
as stimulus size increases so does JND
Magnitude estimation is what type of measure?
suprathreshold (produces physiological effect)
How does magnitude estimation work?
standard stimulus is presented and observer assigns it a number, all subsequent stimuli are rated relative to the standard
Power functions are described by the relationship ?
P = KS^n
P is perceived magnitude
K is a constant
S is stimulus intensity
Choice RT?
requires sensory discrimination and frthur processes
If the number of distractors has no effect on reaction time?
the target attribute was preattentive
What are the functions of hearing?
signalling events we cannot see, communication
Is the compression or air moving in a sound wave?
the compression
The change in compression of air molecules is a _____ wave?
sine
Where the max amount of pressure in a sine wave? Least
the crest
the trough
lower frequency equals _______ pitch?
lower
Higher amplitude means what for sound wave?
louder noise
What is the equstion for decibels?
dB = 20 x log(p/po)
p is sound pressure
po is standard pressure (20)
What is the pain threshold (dB)?
140 dB
What is the decibels of normal speaking voice?
60 dB
Pure tones are?
single sinusoidal wave
What is fundamental frequency?
lowest frequency present and also referred to
as the first harmonic
What is the harmonic?
frequencies which are multiples of the fundamental
frequency
What is the Fourier spectrum?
plot showing sinewave components of a sound
What is Fourier synthesis?
adding together frequencies to create a complex tone
WHat is Fourier analysis?
the process of decomposing a complex tone into its component frequencies/harmonics
What instrument produces the sound closest to a pure tone?
flute
Using magnitude estimation they found that increasing perceived loudness by a factor of 2 increases decibels by?
10 dB
What is the range of frequencies humans cna hear?
20 - 20000 Hz
What is the name of graph that plots all frequencies we can hear and the intensity required to hear them?
audibility graph
Equal loudnness curves are?
show how loud a tone of a particular
frequency has to be to match a standard tone of a given
frequency and loudness.
Perceived loudness is determined by?
sound pressure and frequency
Is pitch physical or psychological?
psychological
What is the effect of removing the fundamental frequency of a sound?
get sound w/same perceived pitch but different timbre
What makes up the outer ear?
pinna and auditory canal
What is the purpose of the outer ear?
channels sound to other parts of ear, protects middle ear, intensify some sounds
What makes up the middle ear?
ear drum, ossciles, oval window, round window
What is the role of the ossciles?
enhancec sound pressure before it reaches inner ear
Why does the sound pressure need to be enhanced before entering inner ear?
cause its filled with fluid not air
What principles do the ossicles use to amplify force?
concentration of force, leverage
What is the base of the stapes associated with?
oval window
What is the cochlear partition?
structure that separates the cochlea into two fluid-filled compartments
Auditory nerve fibers are connected to wwhat in organ of corti?
hair cells
What membrane sits on top of the organ of corti?
tectorial membrane
basilar is at bottom
When do hair cells activate?
when the stereocilia are pushed toward the taller kinocilum
ion channels open
Does hair cell activation sync with the sine wave?
yes
What is phase locking?
fire action potentials at particular phases of an ongoing periodic sound waveform
What is the purpose of phase locking?
sound localization, sound detection, pitch perception, and speech understanding
What are the two ways auditory signals can be coded?
frequency coded and pitch codded
Von Bekesy’s travelling wave theory was observed through?
taking pictures of the vibration of the basilar membrane
Higher frequencies peak closer to the _____ of the basilar membrane?
base
Lower frequencies peak closer to the _____ of the basilar membrane?
apex
What do outer hair cells do?
amplify sound
What do inner hair cells do?
primary sensory reeceptor, transmit signals
What is the place theory for pitch perception?
based on the relation between
a sound’s frequency and the place along the basilar membrane
that is activated.
What is amplitude modulated noise?
noise that varies in amplitude, or loudness, in a regular or irregular pattern
What is special about amplitude modulated noise??
not associated with vibration in a particular location on the membrane
Phase locking only occurs for frequencies up to _____?
5000 Hz
pitch perception only occurs up to this
What are two things that are important to pitch perception?
timing of the auditory signal and temporal response
Tuning curves are _____ for higher frequencies?
wider
People can perceive pitch for higher frequencies if?
if many harmonics are present
What is the auditory pathway from inner ear to brain?
auditory nerve -> cochlear nucleus -> superior olivary nucleus -> inferior colliculus -> medial geniculate nucleus -> primary auditory cortex (A1)
What are three divisions of the auditory cortex?
core (A1), belt area, parabelt area
What direction does info travel in auditory cortex?
from core to belt to parabelt
gets more complex as you go
As nerve impulses travel along the auditory pathway to the
cortex temporal information becomes ?
less important
Phase locking in the CORTEX only occurs up to _____ Hz?
100-200
T/F, individual neurons in cortex seem to respond to pitch
True
Do neurons that are more anterior or posterior react more to pitch?
anterior
Where is pitch perception believed to occur? Why?
beyond cochlea
cause periodicity pitch is perceived even if two differnet tones are presented to the ears
Does the auditory cortex respond if sounds are played while subject is sleeping?
yes, ressponses were approx 10% weaker, some neurons are more active than others
What is conductive hearing loss?
sound waves are blocked from reaching inner ear
damage to ear drum, build up of ear wax, etc
What is sensorineural hearing loss?
damage to parts that send nerve signals (hair cells, auditory nerve, auditory cortex)
What is the most common type of sensorineural hearing loss?
presbycusis (age related hearing loss)
also could be caused by loud noises, drugs
Presbycusis affects males or females more severely?
maales
Cochlear implants are made up of?
microphone, sound processor, transmitter, receiver, electrode
Where are the transmitter and receiver mounted in cochlear implant?
mastoid bone
Where is the electrode stimulating in coclhear imp;ant?
cochlea to stimulate auditory nerve fibers
What is azimuth?
horizontal plane meaasured in degrees, from left to right
What is sound localization?
ability to determine the direction and distance of a sound source
What is interaural level difference?
the difference in loudness between the left and right ears
head causes acousitc shadow
What is the interaural level difference useful for?
useful for high frequency (>1000 Hz), located to one side of the head
Is interaural level difference a binaural or monaural cue?
binaural cue
How does acoustic shadow relate to the sound frequency?
acoustic shadow does not happen if object is smaller than the frequency (no disruption)
What is interaural time difference?
when sound reaches one ear before the other
Interaural time difference can trigger azimuth only if?
the sound is not directly in front of behind
strongest when directly beeside
What is the impact of frequnecy in interaural time difference?
higher frequnecies is less obvious where it is coming from
What is the cone of confusion?
cone-shaped area where the location of a sound source is uncertain
Is interaural time difference a monoraul or binaural cue?
binaural
What is the pinnae monaural cue?
distinctive shape of pinna cuases sound waves to be changed from depending on where they came from
Where is pinnae cue most useful?
along the vertical midline
What are spectral cues used to judge?
the elevation of sound
Spectral cues are created by?
the head and the pinnae
Are ILD and ITD effective for elevation?
no
What is HRTF?
head-related transfer function
describes how the human head and ear canals alter sound
Did experiement wher HRTF and ILD where varied and ITD was the same, what did participant suse?
used ITD, especially when low frequency
If people wear a mold that smooths their pinna what happens?
they will eventually adapt and improve
Does visual imput effect sound localization?
yes it has a large effect
What provides distance input for sound?
loudness/sound pressure, frequnecy, reverberation, movement paralax
How does frequency impact distance input>
high frequency noises tend to be closer
How does reverberation/reflection impact our distance input?
sounds that are further
away tend to have more indirect components
What are the 2 mechanisms proposed for the physiology of auditory localization?
narrowly tuned ITD neurons
broadly tuned ITD neurons
What is narrowly tuned ITD neurons?
specificity coding, found in inferior colliculus and superior olivary nucleus
What is Jeffres model for narrowly tuned ITD neurons?
Coincidence detectors fire only when signals arrive from both
ears simultaneously
What is broadly tuned ITD neurons?
distributed coding system
Location of sound is indicated by the ratio of
responding for two types of neurons
Is the What stream in auditory cortex ventral or dorsal?
ventral
Is the Where stream in auditory cortex ventral or dorsal?
dorsal
Where the the what stream start/end?
starts in the anterior portion of the
core and belt and extends to the prefrontal cortex
Where does the where stream start/end?
starts in the posterior core and belt and extends to the parietal and prefrontal cortices
What is direct sound?
sound that reaches the listener’s ears straight
from the source
What is indirect sound?
sound that is reflected off of environmental
surfaces and then to the listener
When a listener is outside most sound is?
direct
What is the precedence effect?
when two similar sounds arrive at the ears very close together in time, the listener perceives a single sound localized primarily based on the direction of the first arriving sound
What is echo threshold?
the delay between when a sound is perceived as one fused sound and when it is perceived as two separate sounds
The echo threshold varies depending on?
the elevation of the stimuli
What is intimacy time?
time between when sound leaves its source
and when the first reflection arrives
What is the best time for intimacy time?
around 20 ms
What is bass ratio?
ratio of low to middle frequencies reflected from
surfaces
What is the best bass ratio?
high bass ratio
What is the spaciousness factor?
fraction of all the sound received by
listener that is indirect
What is the best spaciousness factor?
High spaciousness factors are best
What is auditory scene analysis?
process by which sound sources in the
auditory scene are separated into individual perceptions
What are the auditory grouping principles?
location, similarity of pitch and timbre, temporal proximity (sequencing), onset and offset, good continuation - auditory continuity, experience
What is auditory stream segregation?
the process of perceiving multiple sounds as separate sources
What is Deutsch scale illusion?
two series of unconnected notes appear to combine into a single recognisable melody, when played simultaneously into the left and right ears of a listener
What is melody?
the experience of a sequence of pitches as
belonging together
Melodies can be divided into?
phrases
The average interval within a phrase i?
2.0 semitones
The average interval between the end of one phrase and the beginning of another is?
2.9 semitones
________ notes tend to occur at the end of phrases?
longer
What helps indicate which notes belong to a single stream?
smaller intervals between notes, tonality, expectation
What is the ventriloquist effect?
an observer perceives the sound as coming from the visual location rather than the source for the sound
(visual capture effect)
Does visual deprivation cause improvement in auditory perception?
yes
What is temporal structure ?
the time dimension of music, which consists of a regular beat, organization of the beat into measures (meter), and the
time pattern created by the notes (rhythm)
What is timbre?
quality of sound that distinguish musical instruments from each other
Does music have an adaptive function?
YES its role in social bonding and group cohesion.
What are some common aspects of music across cultures?
elicits emotions, performed in social contexts, tones separated by octaves are perceived as similar, sequences of notes close in pitch are perceived as part of a
group
Musical training has been linked to?
better performance in math, better emotional sensitivity, improved language skills, greater sensitivity to timing
What is MEAM?
music envoked autobiographical memory
music triggers a memory for something you experienced
What non medical thing has been used as a therapeutic tool for people with alzheimers?
music
How does music impact people w/alzheimers?
improves their memory
What are some areas of the brain activated by music?
motor/sensory/auditory/ prefrontal cortex
hippocampus, cerebellum, amygdala, nucleus accumbens
A connection was demonstrated between the beat of music and what brain structure?
basal ganglia
How do brain waves relate to beat of music?
they ossiclate in time with the beat
What is meter?
the organization of beats into bars/measures
What is the inter onset interval?
the time between the onset of each note.
What is it called when notes occur on the off beat?
syncopation (common in jazz and pop)
How does a persons language influence their perception of grouping?
the stress patterns influence it
The most stbale note in any key is called?
the tonic
What is the cognitivist approach to emotion in music?
listeners can perceive the emotional
meaning of a piece of music, but that they don’t actually feel
the emotions.
What is the emotivist approach to emotion in music?
a listener’s emotional response to music
involves actually feeling the emotions.
What emotions were major keys associated with?
happy and peaceful
What emotions were minor keys associated with?
scary and sad
What emotions was slow tempo associated with?
sad and peaceful
What emotion was fast tempo associated with?
happy
What part of the emotional experience of music is the nculeus accumbens associated with?
pleasurable experiences
“chills”
What is congential amusia?
don’t
recognize tones as tones.
cannot recognize music but can with language
How do we produce vowels?
vibration of the vocal cords and changes in the shape of the vocal tract by moving the articulators
What are formants?
frequency peaks in the human vocal tract that are responsible for the quality of speech sounds
What make up the articulators?
tongue, lips, jaw, soft palette, teeth
How are consonants produced?
constriction of the vocal tract
Which formant has the lowest frequency?
first one
What are phonemes?
smallest unit of speech that changes meaning of
a word
How many phonemes does english have?
47
What is the varaibility problem?
there is no simple correspondence
between the acoustic signal and individual phonemes
Variability in speech comes from?
a phonemes context and variability from different speakers
What is the Mcgurk effect?
if visual stimulus and auditory stimulus are different observer will hear mid point
ga ga and ba ba makes da da
How is vision and speech linked phsyiologically?
same brain areas activate for lip reading and speech perception
FFA is activated when hearing familiar voices
What is the phonemic restoration effect?
auditory illusion where people perceive missing phonemes in a word
happens when cough/tone replaces a phoneme in a word
What is the segmentation problem?
there are no physical breaks in the continuous acoustic signal
(how to tell changes)
What is word segmentation affected by?
affected by context, meaning, and our
knowledge of word structure.
What is transitional probabilites?
measure of how likely a symbol will appear, given a preceding or succeeding symbol
What type of processing is important for our ability to understand speech?
top down processing
