How did music happen? Part 2: “Spartans, Chimps & Neurons”
This is a part of a series of articles. Click here to go back to Part 1: “Digging”
The neural symphony
It’s pretty obvious we can all perceive music as such and thus have something in our bodies which has the specific function of extracting and interpreting information in a musical form. To explore this notion further, we should first look at what happens in the grey blob that lives inside our head, called brain, when we listen to music.
Music is certainly and definitely a combination of vibrations in different frequencies. But these vibrations, however perfectly ordered they may be in a mathematical sense, have no musical value by themselves. There is no music in the equations. We need some kind of mechanism to animate them. We need our ears to convert sound vibrations to neural signals. Pressure waves fire different electrical charges inside our brain depending on pitch. Then the electrical charges go to the auditory cortex. The part of the inner ear that actually converts sound vibrations to neural charges is called the cochlea. This amazing little gadget is strangely laid out in pitch order, much like a piano keyboard – its “hair cells” are wired up to the auditory cortex in such a way that lower notes stimulate cells on the left and higher ones – cells on the right.
Until recently scientists thought there was a music center inside the brain and kept trying to locate it. We now know that very different areas of the brain are responsible for extracting the signal from sound and turn it into music. If you look at a brain scan of a person who’s playing or listening to music you’ll see a bunch of coordinated and non-coordinated firing in different parts of the brain – a neural symphony where each instrument plays its own important part.
Pitch is processed in one set of neural regions, tempo in another set, loudness in another and other groups of neurons are responsible for timbre. The whole picture comes together later – in this case a few thousands of a second – so rapidly, you never know that the elements were ever separate.
It seems we’re just wired up for music. Even people who are not that good with music have some musical memory. Even if we don’t have a good sense of pitch or rhythm, music still “moves” us which can be seen in the immediate response of our motor functions when we hear a tune we like – the urge to dance.
Music is symmetrical. Tempo and rhythm are the obvious proof for this. Symmetry is very unusual when it comes to naturally occurring phenomena and it’s weird to see, or in our case – hear, it while you’re strolling through a forest, for example. Rocks and plants, and clouds, and rivers are almost never symmetrical. Animals, on the other hand, are. If something is symmetrical it’s most likely alive and things that are alive are definitely things you need to watch out for. In nature, symmetrical stuff will usually be a) something you want to eat; b) something that wants to eat you; c) something you want to have sex with. This would mean that animals, including humans, are likely to have somewhere in their genes a strong instinct to pay serious attention to symmetry. If this is true, our predisposition to music has just become more logical in an evolutionary sense.
Chimps and Spartans
A good next step to figuring out how human music is would be to explore how other contemporary species, which we can at least observe, that are close to us from an evolutionary viewpoint, use sounds for communication. The logical candidate for such an observation, of course, is our closest genetic relative – the chimpanzee. Thorough research has been made on chimp behaviour and some of the findings are very closely related to what we might be looking for.
Chimps use sound as an instrument of identification. They’re extremely territorial and are more fight over land than over females. Other animals often physically mark their territory – chimps don’t. They drum on tree trunks, stones or the ground, they make sounds with their mouths which are specific for each group living together. In other words, vocalization is crucial for chimps. What’s remarkable is their ability to memorize and produce very complex patterns of sounds in order to uniquely identify themselves and distinguish themselves from other groups of chimps. The more complex the sounds the better. They serve as a symbol of group identity and each chimp is expected to learn and be able to repeat them. An equivalent to this in human culture would be national anthems.
Okay, how exactly would a “song” sang by a group prevent another group from invading its territory? The answer is teamwork. It’s a question of impression and logical assumptions. The more complex the combination of sounds, the harder for members to memorize it and learn to produce it in a synchronized manner. The better the synchronization, the better the group works together, obviously. The better a group works together, the more you should be afraid to mess with its food, females and territory.
Apart from being an identifier of team efficiency and power, complex chimp “anthems” make it harder for members of rivaling groups to infiltrate a group by imitating its signature sounds. This can explain an evolutionary need for variation. Some chimp groups have even been known to make changes to their “songs”, or add new elements to it, if there’s a rivaling group nearby whose sound patterns noticeably resemble their own.
Vocalization was also very important for communication within the group, demonstrating the higher ability of an individual to memorize and produce the particular sound pattern. This shows other males, for example, that he’s smart and able, and not to be taken lightly, and is a sign for females that he would be a good choice for a mating partner. Variations in pitch came along later as additional means to impress females and competitors, or so we believe.
So why did I mention Spartans? In the movie ‘300’ we see a very good example of this. Watch this scene:
When king Leonidas is asked by Daxos, leader of the Arcadians, why he didn’t bring more soldiers to fight the armies of Xerxes, he first asks a few of the Arcadians what their profession is and gets answers like ‘potter’ or ‘blacksmith’. Leonidas then asks his own men: ‘Spartans! What is your profession?’. In response he gets three perfectly timed and fairly intimidating shouts demonstrating the fierceness and iron discipline of the Spartan warriors. Leonidas turns to Daxos and says: ‘See, old friend? I brought more soldiers than you did.’
This may not seem such a big deal but let’s look at the details. First, the Spartan soldiers need to have done this exact same thing a thousand times in order to be able to perfectly do it every time. They need to recognize the signal in the form of an exact question, which means they’re fully concentrated and are constantly paying attention to their surroundings. Then, they need to have a perfect sense of timing to know when exactly to start the first shout after the question was asked. Finally, the number of shouts is three, which is the minimum number of consecutive sounds needed to identify a repeating pattern, measured by the duration of the gaps between them. What the Spartans are basically saying is ‘Don’t mess with us’.
Stay tuned for Part 3: “The Mafa and the Octave”
…meanwhile make sure to check out our other awesomely great articles or head over to Drooble for more Music!