task 8 Flashcards
(36 cards)
hearing impairments
conductive hearing loss - sound waves don’t reach the inner ear
hearing aids:
analog hearing aids: they convert sound waves into electrical signals and amplify all sound equally
digital hearing aids
They convert sound waves into digital signals. They are processed by an algorithm to adjust the sound to user’s needs, and then sent to the ear. They amplify sound selectively and suppress background noise.
But they can produce feedback (=whistling noise, picked up from the hearing aids’s microphone), so they have cancellation systems to reduce it.
cochlear implants
They have a microphone (to pick up sounds), a sound processor (to amplify sound waves), and a reciver ( to send to the cochlear).
But there is a lot of interference -> speech perception is good but music and pitch perception is bad: because of spatial and temporal cues.
sensorineural hearing loos
due to exposure to loud noises
* sound waves are not processed correctly: poor pitch perception and difficulties in distinguishing music features like melody
*cochlear implants can help
Music illusions
we hear sound that seems to be continually increasing in pitch, but in fact it’s a loop
a tone starts and before it reaches its end (octave above), another tone starts with a lower frequency, creating a loop effect->
proximity and good continuation
Octave illusion
through earphone, one tone is presented to one ear, and then another tone exactly an octave higher or lower is presented to the other.
*right-handed people perceive the higher note in the right ear, even if we reverse the earphones
*due to differences in pitch processing between the right and left auditory cortices.
closure, proximity
scale illusion
each ear is presented with a different pattern, one ear hears a descending scale while the other, as ascending scale-> proximity and good continuation
tritone paradox
similar to Shepard tone but with tritones )half octave). Tritones are placed one after the other. People hear differences in pitch: either ascending or descending.
music in the brain
tonotopic organization: every part of the brain is specialized and sensitive to a specific frequency and pitch
*primary auditory cortex: specialized in rhythm : mostly right hemisphere
*secondary auditory cortex: specialized in music perception:
-mostly right hemisphere because it’s more sensitive to small changes in pitch, making it more important for music rather than speech
-music training can make the left hemisphere more and more sensitive.
-includes rhythm processing
the neuroscience of music
the auditory nerve perceives a representation of the frequency of sound- the auditory signal has a tonotopic organisation !
hemispheric asymmetry
music perception cause activation in the right temporal lobe
the more musical training someone has, the more the left hemisphere becomes involved
secondary auditory cortex
musical stimuli are processed, independent of other sounds
Rythm is processed in the primary auditory cortex
right hemisphere (predominantly)- belt and parabelt
left hemisphere- left PFC, left parietal cortex
cerebellum: because people producing rhythm are engaged in action
superior temporal gyrus
specialized in understanding speech
Planum temporal and Planum polare: are activated by music
when music and visual systems are connected
Synesthesia- condition in which stimulus in one sense triggers response in another sense
visual areas of the brain are activated when people are listening to music : music-> thoughts-> invoke images
color-music synesthesia
when pitches, notes, or chords elicit experiences of particular visual colors
there are stronger connections between the sensory area like visual and auditory areas and the frontal lobe
amusia
condition in which brain damage interferes with music perception
congenital amusia
individuals are born with an impairment in music perception: they aren’t able to discriminate between pitches and consonant/ dissonant music
music perception with cochlear implants
hearing loss usually occurs in high-frequency sounds
problems with hearing aids/cochlear implants
- slow transmission from the receiver to the cochlea
- tampering the sound at loud volumes to protect the ear-> especially bad for musicians
3.the main function of cochlear implants is speech perception-> Pitch perception is very poor
->hard to perceive musical features, like harmony
- the effects of compression: live or recorded music
- dendrite death, demyelination, soma death
gestalts principles of melody
*proximity- elements near each other are perceived as a group: similar in pitch, notes, time and space
*similarity- elements that are similar are perceived as a group: same timbre
*closure- a complete pattern of melody usually ends with a tonic note
*good continuation- smooth continuity is preferred
a note close in pitch follows a pervious note
Proximity
elements close in pitch, time or space are seen as belonging together
ex: playing the piano- right hand play the melody
left hand plays the accompaniment
- grouping by pitch
similarity
musicians are playing the same notes with the same instruments -> approximately the same timbre
+ once a melody has been established-> it’s similar even across change of instruments
closure
a melody should end on the tonic note of any of the scales (or a close enough note)
-> our expectations of what to hear can actually create the perception of the note
