1. Music and Mind III The Hearing of Music www.mind-study.org Chopin nocturne Op. 9, no. 2 Yundi Li 4:00 ♫

2. Where we are.. I.The Appeal of Music II.The Sound of Music III.The Hearing of Music IV. The Structure of Music V.The Making of Music VI.The Power of Music 2

3. Topics for today Introduction The Ear The Brain in Music Perception 3

4. A couple of technical terms Acoustics – (last week) Psychoacoustics – (this week) 4 A scientist’s objective description of a phenomenon observed on planet Earth. Jourdain 1997: xif

5. Topics for today Introduction The Ear The Brain in Music Perception 5

6. Perception of Sound Hearing was the last sense to develop Human brains can handle patterns of sound far more complex than the brains of any other animal (Jourdain 1997:4U) Playing a waltz to a goldfish; … to a dog or cat; … “When a brain isn’t up to the job, nothing occurs…” (ibid. 5T) “… a good ear for music …” ? – Really it is a good mind for music 6 “…every molecule in a concert hall sums every vibration from every instrument into one frenzied dance. Think of what a remarkable device it would take to watch that dance and infer from it every one of the original vibrations. Yet that—and more— is precisely what an ear does.—Jourdain 1997: 7

7. The ear (I) (1) On the outside: the pinna (pl. pinnae) – Just a funnel (a pretty fancy one) – Pinnae are a late evolutionary development Pinnae enhance certain frequency ranges – High frequency components – They also resonate to amplify certain high frequencies These frequencies are also important for speech perception The real ear is inside the head (2, 3, 4, 5) (2) the ear canal, about 1 inch long, resonates to boost higher frequencies 7

8. The Ear (II) (3) the ear drum – Converts the pressure wave of air into mechanical motion (4) the middle ear: has three little bones (ossicles) – Hammer – Anvil – Stirrup (5) the inner ear 8

9. The Ear (III) (4) The middle ear (with its 3 occicles) – Concentrates the vibrations to 1/16 th as much area at the entrance to the inner ear as at the ear drum – The ossicles enhance middle frequencies—important for speech – Fish have no middle ear – Amphibians, reptiles, and birds have a middle ear with only one ossicle – The 2 additional ossicles of mammals boost the range of audible frequencies (5) the inner ear – Filled with fluid 9

10. The inner ear Converts vibrations into neurological signals – Information in a form that the brain can use The inner ear functions as the retina does for vision – The outer and middle ears are like a lens Filled with fluid Contains three narrow chambers 1 ½ inches long – They are coiled 3 ½ times for compactness – Hence the name cochlea, from the Latin word for snail The middle chamber contains the organ of Corti 10

11. The cochlea 11

12. The organ of Corti Contains groups of tiny hair cells From which tiny hairs project Each group sensitive to a particular frequency The cells are connected to neurons About 14,000 receptor cells Connected to about 32,000 nerve fibers The nerve fibers extend from the cochlea, as the auditory nerve, to the brain 12

13. Frequency and amplitude of things we commonly hear 13

14. Hearing vis-a-vis Vision The interface: converts input to neural signals – Vision: the retina – Hearing: the organ of Corti (in the cochlea) Number of neurons involved – The retina has 100 million receptor cells Optic nerve has over 1,000,000 fibers – The organ of corti has 14,000 receptor cells Auditory nerve has 32.000 fibers Localizing the stimuli – Fairly obvious for vision – There is no way for one ear to know where the vibrations are coming from 14

15. Evolution of hearing First primitive hearing developed in fish – But fish don’t have a true inner ear Amphibians have primitive inner ears – With one ossicle Reptiles are sensitive to a broader frequency range Birds, broader yet – Sensitivity up to 10,000 Hz – But birds don’t hear bird calls as well as humans The whole evolutionary development up to human hearing.. – About 500 million years – Over 100 million generations 15

16. Means of Localizing sound Turning the head – For example, till both ears hear the sound at the same time More often, “calculation” by the brain, based on.. – Different time of arrival at left and right ears – Differing intensity of sound received by left and right ear – Differences in how sound is reflected in the pinnae We can also estimate the distance of a sound’s origin – Higher frequencies are more easily lost as distance increases – Our brains learn over time to estimate on basis of experience Humans can detect difference in horizontal position of about 1 degree for sounds of around 1000 Hz 16

17. How Good is Hi Fi? A stereo in your living room vs. being in a concert hall In a concert hall, vibrations from all over the orchestra plus reverberations from all over the walls and ceiling In your living room, two speakers present vibrations – From two microphones in a concert hall – All the vibrations come from the two speakers – They then re-reverberate around the walls and ceiling of the room The result is muddled You don’t get much improvement from using multiple mikes at different locations in the concert hall Live in a concert hall you have only two “mikes” — ears – Both receiving vibrations from all over the concert hall 17

18. How Good is Hi Fi? A stereo in your living room vs. being in a concert hall 18 “If music’s spaciousness is important to you, there’s no alternative to a good concert hall.” —Robert Jourdain (1997:24)

19. Topics for today Introduction The Ear The Brain in Music Perception 19

20. Processing of sound by the brain Basic brain anatomy Basic brain anatomy The ear converts vibrations to neural signals – Only the first step From the auditory nerve to the brain stem From brain stem to cortex 20

21. Processing of sound by the brain stem Nuclei — – Each with hundreds of millions of neurons – Intricately connected to one another and to the cortex Auditory nuclei – Cochlear nuclei – Olivary bodies – Inferior colliculi – Superior colliculi Auditory analysis for points along range of frequencies – Relative loudness at each ear – Time of arrival at each ear – Changes in frequency – Changes in volume – Relationships to visual input – Etc. 21

22. From brain stem to cortex By the time the neural signals reach the cortex, an enormous amount of processing has already been done The process of hearing music as music is largely cortical – Analysis of Tone Melody Harmony Rhythm Etc. Relies on information about basic structures – Scales – Rhythmic pattern – Etc. 22

23. Scales and categorial perception Scale: a division of the continuum from octave to octave into a discrete number of steps In most Western music, 12 steps Prerequisite for a scale: categorial perception Each step along the scale is a category We can distinguish differences within a category – To some extent – If we pay attention – But normally we don’t But a tone right on the borderline tends to sound “awful” 23

24. The mind at work Categorial perception is also important for language – And for thinking in general – It is at the heart of nearly all mental activity When we think we are operating directly with the world – We are really operating with our mental constructs – Several steps removed from the actual world So also with music – What we hear as a tune with harmony and rhythm is largely a system built within our minds – Heavily dependent on our prior experience with that kind of music – Only indirectly related to the external events leading to the auditory input 24

25. Advantages of the Pythagorean scale (12 tone) 12 notes is – not too many for efficient brain processing Compare Indian scales, with many more tones – not too few for rich and interesting possibilities Compare pentatonic scale Provides for harmony that is natural – 5ths, 4ths, 3rds, etc. that are present in harmonics So harmony developed in Europe but not in India – Compare Roman vs. Arabic numerals 25

26. Melodies and the mind Melodies affect us because our minds make sense of them How? (1) short-term memory allows a sequence of notes to be present together (2) they include relationship to harmony makes them easy to grasp (3) they include a certain amount of rhythm makes them easy to grasp different notes have different durations different notes have different accentuation 26

27. Melody vis-à-vis rhythm and harmony Notes that fall on important rhythmic junctures – Are usually the most important notes in a melody Often introduce change of direction Often go with harmonic changes 27

28. Melody and theme Melodies—typically last for about 30 seconds or more – As in songs Themes—smaller fragments strung together – Maybe repeated, modified, intertwined Forming a “melodic landscape” – Lasting for up to a few minutes More difficult to grasp than a simple melody – Common in classical music, sometimes in jazz – Example: Beethoven’s Eighth Symphony, 1 st movement ♫ ♫ 28

29. Melody and theme (cont’d) Wagner mocked Rossini, for writing: “…the naked, ear-delighting, absolutely melodic melody” According to Jourdain (1997:83), “Musicologists point out that most composers become less ‘melodic’ and more ‘thematic’ as they grow older and take on more ambitious projects.” 29

30. Melody and the brain Brain must track the melody’s contour – While tracking the harmony Recognition of tones takes place mainly in right temporal lobe So also for melodies – Evidence from playing melodies to each ear separately and testing how well they are perceived or remembered – Left ear is clearly superior Left ear channels sound to RH, right ear to LH – Additional evidence from EEG and brain scans – Additional evidence from results of surgery Melody perception is undermined by excision of right temporal lobe 30

31. Context and the role of mind On another note: the role of context – Example: consider two successive A’s – Example: Beethoven’s Third Symphony, 1 st movement ♫ (ca. 3:00) ♫ Works because of short term memory One reason we like music: – An exercise for the mind 31

32. Harmony and the brain Recognition of chords: – Also mainly in right temporal lobe LH and RH in tone perception – Tones that are rich in overtones are processed mainly in RH – Pure frequency tones are processed equally on both sides E.g., flute produces few overtones Relationship to language – Consonants are perceived mainly in LH – Vowels are perceived mainly in RH – Vowels are distinguished from one another by their overtone structures 32

33. Harmony and the brain: Development By 3 to 5 years of age, children are fairly good with – melodic contours – Simple meter But no good at recognizing harmonic consonance and dissonance By 5 years, a sense of harmonic relations – Younger children (and some older ones) often shift keys while singing a song By 7 to 8 years of age – Able to distinguish relative consonance and dissonance – Can distingish major and minor keys By 10 years of age can follow two parallel voices Full harmonic comprehension not until 12 or later – In many people, never 33

34. Role of Left Hemisphere Operates in harmonic analysis along with RH – but not as much as RH Prominent in analyzing rhythmic patterns – Incl rhythmic patterns in melodies General principle: For almost everything of any complexity, multiple parts of the cortex work together Professional musician and music theorists make more use of LH in analyzing melody and harmony 34

35. Harmony and the Brain “…the coincidence of harmony perception and melody perception in the right brain suggests that harmonic structure is the key to great melody,” —Jourdain (1997: 87) Harmony in the development of Western music – From melodic contour to harmonic melody to pure harmony – About seven centuries of development 35

36. Historical Development of Harmony (I) Harmony developed late in the development of Western music Over a period of about seven centuries Beginning with chants of medieval Christian monks – No rhythm apart from that provided by the words Next stage: polyphonic chanting Shift of emphasis on sequential relations among tones – To harmonic relationships of simultaneous tones By 16 th century, a lot of harmonic experimentation – The Baroque period, beginning about 1600 – Harmony along with contrasts in tempo, volume, different instruments or groups of instruments 36

37. Historical Development of Harmony (II) Each next generation of composers experimented further with harmonic structures – Including from Bach to Handel & Haydn, to Mozart to Beethoven to Schubert, to Chopin, to Wagner … Each new development was taxing to the brains of audiences until they learned to cope and then appreciate With just 12 notes to the scale, there is a limit to this process— can’t go on forever “The listener increasingly was asked to perceive the most subtle hints of harmonic action and to remember hierarchies of key changes over periods of many minutes.” (Jourdain 1997:98) 37

38. Historical Development of Harmony (III) Each next generation of composers experimented further with harmonic structures, until.. Schoenberg: Serialism – No tonal centers, no anchor points for hierarchies of intervals – Discourages repetition of any kind Short-term memory can’t handle it – Laboratory studies consistently show that even professional musicians do poorly on tests of any kind that employ serial music “What a composer’s intellect can imagine is not necessarily something that a listener’s auditory system can perceive.” (Jourdain 1997:100) More from Jourdain 1997:100 38

39. Chord sequences Some chord transitions flow smoothly—consonance – Mainly to neighbors in the circle of fifths – Others grate on the mind—dissonance “There’s abundant laboratory evidence that we perceive near-key progressions more quickly and accurately than others. Harmony is easy to follow (and often banal) when chords move merely from one adjacent key to the next” (Jourdain 1997: 107) 39

40. 40 T h a t ‘ s i t f o r t o d a y !