A theory of music cognition Day 4

1. A theory of music cognitionDay 4 Music Cognition MUSC 495.02, NSCI 466, NSCI 710.03 Harry Howard Barbara Jazwinski Tulane University

2. Course administration • Spend provost's money Music Cognition - Jazwinski & Howard - Tulane University

3. A theory of music cognition

4. What question should a theory of music cognition answer? • It's not a rhetorical question. Take a few minutes to discuss it with someone. • Some answers I've found, with no pretence to authority: • What happens when I hear music? • How do I hear music? • What y'all have said • how does the brain perceive and interact with music? • what is music; what is cognition? • how does the brain differentiate between music, language, and noise • course objectives • how does the brain interpret the external stimuli of music and process it into something meaningful? • how does the brain integrate all the parts of music? Music Cognition - Jazwinski & Howard - Tulane University

5. My answerdrawn from language cognition • What will the next note be? • Advantages • It joins perception and production • What is the next note that I will hear? • What is the next note that I will play? • It is easy to verify • It is easy to quantify • Disadvantages • It ignores the emotional content of the next note • What will the next note be, and will I like it? Music Cognition - Jazwinski & Howard - Tulane University

6. This is a question of predictionHere's an example • Sitting in my living room, I hear my wife call "mail’s here!" from the next room, and within a few seconds I am heading toward the front door to retrieve the day’s offerings from the mailbox. • But what just happened? • Take a few minutes to discuss what just happened with a friend. Music Cognition - Jazwinski & Howard - Tulane University

7. What just happened • A pattern of sound energy impacted my ears, which I decoded as the words "mail’s here" spoken by my wife. • I infer • that there is mail waiting for me, • that I am being given an oblique instruction to pick it up, • and that there is indeed something worth picking up. Music Cognition - Jazwinski & Howard - Tulane University

8. But none of these inferential leaps is infallible • It is possible • that the words spoken were not "mail’s here", but "Mel’s here" – an unexpected visit from our neighbor Mel; • or that, although something did indeed come through our mail slot, it was not the U.S. mail but a flyer from a local restaurant; • or that the mail has been delivered, but is nothing but junk (the most likely possibility); • or that my wife simply said "mail’s here" as an informational update, and has already gone to pick up the mail herself. • My pondering of the situation reflects all of these uncertainties, and the complex interactions between them. • If I don’t actually have a neighbor named Mel, for example, then the probability that my wife said "Mel’s here" is decreased. Music Cognition - Jazwinski & Howard - Tulane University

9. The next note • But a moment later, these dilemmas are largely resolved. • I hear a louder, clearer, more insistent "The mail is here!" from my wife, • which clarifies • both the words that were spoken • and the intent behind them – she does expect me to get the mail. • (Whether the mail contains anything worth getting remains to be discovered.) Music Cognition - Jazwinski & Howard - Tulane University

10. The moral • This everyday situation captures several important things about the probabilistic nature of thought and perception. • Perception is a multi-leveled inferential process • Probabilistic judgments are shaped by our past experience • Producers of communication are sensitive to its probabilistic and fallible nature, and may adjust their behavior accordingly Music Cognition - Jazwinski & Howard - Tulane University

11. Perception is a multi-leveled inferential process • Levels of knowledge in the story • I hear sounds, • infer words from them, • infer my wife’s intended message from the words (and from the way she said them), • and make further inferences about the state of the world. • Each of these levels of knowledge contains some uncertainty, which may endure in my mind • even heading for the door, I may be uncertain as to what my wife said. • As such, they lend themselves very naturally to a probabilistic treatment, where propositions are represented • not in true-or-false terms • but in levels of probability. Music Cognition - Jazwinski & Howard - Tulane University

12. Probabilistic judgments are shaped by our past experience • That is, by our observation of events in the world. • In judging the likelihood • that my wife wants me to get the mail, • or that the mail (not Mel) is at the door, • or that it contains something besides junk, • I am influenced by the frequency of these various events happening in the past. Music Cognition - Jazwinski & Howard - Tulane University

13. Sensitivity to probability • My wife knew that I had not fully gotten her message the first time, • and thus re-conveyed both the words and the intention in an amplified form. Music Cognition - Jazwinski & Howard - Tulane University

14. Relevance for music cognition • Let me rephrase the principles • Perception of music is an uncertain multileveled inferential process. • Knowledge of musical probabilities comes, in large part, from regularities in the musical environment. • Producers of musical communication are sensitive to, and affected by, its probabilistic nature. Music Cognition - Jazwinski & Howard - Tulane University

15. Perception of music is an uncertain multileveled inferential process • In listening to a piece of music, we hear a pattern of notes and we draw conclusions about the underlying structures that gave rise to those notes • These judgments are often somewhat uncertain; and this uncertainty applies not just at the moment that the judgment is made, but to the way it is represented in memory. • In the development section of a sonata movement, for example, we may be uncertain as to what key we are really in; • this ambiguity is an important part of musical experience. Music Cognition - Jazwinski & Howard - Tulane University

16. Perception of music is an uncertain multileveled inferential process, 2 • The probabilistic nature of music perception applies not only to these underlying structures, but also to the note pattern itself. • certain note patterns are probable, others are not • our mental representation of these probabilities accounts for important musical phenomena • surprise • tension • expectation • error detection • pitch identification Music Cognition - Jazwinski & Howard - Tulane University

17. Knowledge of musical probabilities comes from regularities in the musical environment • The probabilities we assign to note patterns and to the structures underlying them are shaped by our musical experience. • Proof of this is seen in the fact that people with different musical backgrounds have different musical expectations, perceptions, and modes of processing and understanding music. • This is not to say • that our musical knowledge is entirely the result of environmental influence, • or that it can be shaped without limit by that environment. Music Cognition - Jazwinski & Howard - Tulane University

18. Producers of musical communication are sensitive to, and affected by, its probabilistic nature • In many cases, music production is affected by perception, adjusting and evolving to facilitate the perceptual process. • This is reflected • in spontaneous individual choices • for example, with regard to performance expression; • and in the long-term evolution of musical styles and conventions. Music Cognition - Jazwinski & Howard - Tulane University

19. Source • The story about probability and its relevance for music is taken from pp. 2-3 of Temperley (2007) Music and Probability. • The library has an e-book version of it, so you can view it online. • Note that Temperley does not propose any particular theory of music cognition, except to imply that whatever it is, it is probabilistic. Music Cognition - Jazwinski & Howard - Tulane University

20. Hypothesis v. 2 • What is the next note probably going to be? • And will I like it? Music Cognition - Jazwinski & Howard - Tulane University

21. Back to our regularly scheduled program

22. Ingredients of music cognition mostly receptive, mostly from Levitin Music Cognition - Jazwinski & Howard - Tulane University

23. Next Monday Perception, §1-2 of Levitin