PSYCH 1XX3 - Audition

what does amplitude represent?

loudness

amplitude

the height of a wave, corresponding to loudness in sound waves and brightness in light waves

loudness

the relative volume of a sound, derived from the sound wave's amplitude

what does frequency represent?

pitch

wavelength

the distance it takes for a wave to complete a full cycle, corresponding to tone in sound waves and colour in light waves

tone

the pitch of a sound, derived from a sound wave's wavelength

what does purity represent?

timbre

purity

the complexity of a sound wave, corresponding to the perceptual property of timbre

timbre

the distinctive sounds that result from constructive and destructive interference of sound waves, derived from a sound wave's purity

pinna

the cone-shaped protuberances on the side of your head that collect sound waves and direct them into the ear canal

outer ear

the initial structure of the ear, containing the pinna, ear canal, and tympanic membrane

auditory/ear canal

a narrowing tube in the outer ear that connects the outside world to the middle ear via the tympanic membrane

tympanic membrane

ear drum; thin membrane at the end of the ear canal that separates outer and middle ear, also known as the eardrum

middle ear

the medial structure of the ear, after the outer ear and prior to the inner ear, containing the ossicles - vibrates ossicles & amplifies sound stimulus, causing the oval window to vibrate

ossicles

three small bones found in the middle ear that amplify sounds from the outer ear to the inner ear

inner ear

the final structure of the ear before neural conduction containing the cochlea, basilar membrane, and hair cells

cochlea

fluid filled tube, ~35mm long, coiled like a snail shell, contains the basilar membrane and hair cells

oval window

small opening in the side of the cochlea - when it vibrates, it causes the fluid inside the cochlea to become displaced

round window

accommodates for the movement of the fluid by bulging in & out accordingly

basilar membrane

a stiff structure in the cochlea, innervated with hair cells, which vibrates at different points along its length according to specific frequencies

characteristics of outer hair cells

more numerous, fewer connections to brain, amplify sound, axons are unmyelinated

characteristics of inner hair cells

less numerous, more connections to brain, send pitch information, axons are thick & myelinated, primarily responsible for transmitting signals

echolocation

process by which a receiver emits sound pulses and analyzes the returning echo to form a perceptual image of objects in the environment

co-evolution

the process by which the evolution and adaptation of traits of one species can directly affect the evolution of traits in another species

longitudinal waves

waves that vibrate parallel to the direction they are travelling; sound waves

transverse waves

waves that vibrate perpendicular to the direction they are travelling; light waves

tonotopic organization

refers to the spatial organization of sound frequency on the basilar membrane and auditory brain structures

organ of corti

inner ear structure that houses the inner and outer hair cells

inner hair cells

there are relatively few of these cells, and they innervate the basilar membrane and send precise auditory signals via the cochlear nerve

outer hair cells

there are relatively many of these cells, and they innervate the basilar membrane and send imprecise auditory signals via the cochlear nerve; they play a larger role in sound amplification

absolute (perfect) pitch

the ability to identify a pitch without reference to an external standard

interaural time difference (ITD)

an auditory cue that results from a difference in time of arrival of a sound stimulus to each ear

interaural intensity difference (IID)

an auditory cue that results from a difference in sound intensity between the two ears

head shadow (effect)

a region of reduced sound intensity caused by the head acting as an obstacle to sound waves

binaural cues

auditory cues that require the use of both ears, usually for localizing sound in space

azimuth

the horizontal angle with respect to the head - i.e. left or right, without elevation

elevation

referring to the vertical localization of a sound source, relative to the head

pinna cues

auditory cues that aid in the perception of sound elevation

superior olivary complex (SOC)

brainstem structure responsible for the initial computing of binaural cues for sound localization

medial superior olive

region in the superior olivary complex responsible for computing interaural time differences

lateral superior olive

region in the superior olivary complex responsible for computing interaural intensity differences

inferior colliculus

midbrain structure involved in integrating information about the spatial location of sound

human range of frequencies (Hz)

20-20,000 Hz

where does a lower pitch sound resonate?

the apex of the basilar membrane

where does a higher pitch sound resonate?

the base of the basilar membrane

how does the Organ of Corti produce an electrical signal?

when vibrations in the basilar membrane displace hair cells in the Organ of Corti, the hair cells convert the frequency of the sound into an electrical signal

cochlear nerve

bundle of the axons from both inner and outer hair cells

where is the primary auditory cortex (A1) located?

in the superior temporal gyrus of the temporal lobe

what happens when 2 notes are too close in pitch?

when 2 frequencies resonate closely together on the basilar membrane, the brain has a difficult time distinguishing them - perception of dissonant sounds, which is unpleasant to hear

relative pitch (RP)

allows your to tell if pitches are higher or lower relative to each other

what happens when people with AP do not train at an early age?

they risk losing the ability as they age

why cannot ITDs and IIDs help with discerning whether a sound is coming from behind or in front of you?

sound reaches both ears at the same time and with relatively the same intensity

where is the superior olivary complex located?

pons of the brainstem

Who hears high frequencies better?

People under 25

Is "Yanny" high or low frequency?

High

At what age is there a loss of sensitivity in the basilar membrane?

25

Goal ball

A sport that relies on auditory localization

Mozart effect

Listening to Mozart's music improves cognitive ability - effect lasts 15 mins for spatial reasoning

Exposure to music scales

Prevent perceptual narrowing and increase in neuroplasticity

What sounds do hearing aids increase?

All sounds, including background noise

Neuro-compensator hearing aid

Increases the volume of specific, relevant information; does this by using an algorithm to learn about how a person hears

Which animals can detect the highest frequencies?

Rodents and bats

Which animals have a larger frequency range than humans?

Whales, dogs, and dolphins

Which animal can detect a lower frequency range?

Fish

Which animals have a smaller frequency range than humans?

Birds and frogs