So in Lesson 5, let's come back to the relationship of vocalization to music. And let's take a look again at this slide that I showed you before and be reminded that the vocal tract has all the characteristics of a musical instrument. And the reason for showing you this again is to make the point that as such the human voice would have been the instrument and it is an instrument as we discussed before. That first produced preferred tonal relationships in song melodies and harmonies, so if you ask the question well, where is music likely to have come from? And why is it that many of the characteristics we're gonna discuss in the remaining modules of the course have the phenomenology that we know in music? The answer is almost certainly that they come from the human voice. Again, not in the current text of language that we're familiar with today. But in terms of ancient pre-linguistic vocalizations that must have been the beginnings of the melodies and harmonies that were first generated by the voice that were much later adopted by primitive instruments and much much later adopted by the music theory that we're familiar with today. So let's just go through that argument in a little bit more detail. So this is just a variation of what I told you at the beginning, but now having gone through the lessons today, we can maybe understand this or appreciate it a little bit better. Human vocalization is the major source of tonal sound signals in the environment. That's a critical foundation for thinking about music, particular tonal music, and why it has the characteristics that we're going to discuss in the upcoming modules. And, the reason for its importance is that these vocal signals, and again they don't have to. We think of language today as being a means of conveying lexical information. But of course that quite apart from its modern incarnation as the 6,000 languages that exist in the world today. Pre-linguistic vocalizations conveyed enormous amount of biologically important information. This has to do with the information about the speaker's size. A big person has a much lower, the voice has a much lower set of frequencies, generates lower harmonic series than a smaller person. The gender of the person is revealed that way, the age of the person whether it's a kid or an adult is revealed that way. The emotional state of the person is revealed. You know very well when a person is bored or sad, or happy or angry from the way tonalities are being expressed. Again, it doesn't have to be In terms of words, and of course by the timbre you can identify the individual speaker most of the time. So the point is that identifying and attending to vocal sounds would have been biologically critical for our species. Without this information, we wouldn't have done nearly as well as we did do. And by the way, this information is not limited to human beings and human perceptions of sounds. I mean it's obvious, I mean I think if my dog was a medium sized dog, I mean when he barks or growls, you can tell that he's not a chihuahua, he's a pretty big dog. That's just as important for other animals as it is for us, we use it to greater advantage perhaps and certainly in more subtle ways. But it's generally present in biologically vocalizations. So, the general point that I wanna make finally that I made in the beginning but I re-iterate here is that we should because of their biological value especially, be attracted to vocal sounds and this has been demonstrated in a lot of different ways and this is not anything special, again to vocal sounds. We're attracted to things that have biological value and biological reward for us ultimately in terms of survival and reproduction. But you don't have to think about it in such basic terms. We are attracted to any sensory signal that provides information that is useful to us. Whether that signal involves food and our great liking of foods that have caloric content like sugar. Or in any context the information that pertains to potential mates and many other contexts in which you can think about this. We're especially attracted to the sounds that are important in the same way that we are attracted to other sensory qualities that are important to us for biological survival, for nourishment, for reproduction, and so on. So this is not anything special. This is absolutely fundamental, but again, if we want to understand music, the point of all this is that we have better be able to think about it and understand it in terms of its biology as well as in terms of the esoteric things that modern music theory and our knowledge of music today is more often concerned with. So let me then sum up the main points of the module for today. First of these is that evolution of our tonal sense comes from vocalization and it's biological values. I've just explained that in vocalization what we hear doesn't accord with physics. That's really fundamental. We've gone over that a number of times. And again, there's evidence in vocalization that's the case, is what we've talked about mainly today. Rather what we here accords with accumulated auditory experience, both in the context of intensity and the loudness we hear in response to intensities and frequencies, and the pitches that we hear in response to those frequencies. And the overall [COUGH] idea is that this framework provides a beginning for understanding music and it's attraction in biological terms. Which is gonna be the essence of the remaining modules of the course. So next time we're gonna to continue this same conversation by pursuing music further and its appeal in biological terms.
