The oldest record of notated music, the Hurrian “Hymn to Nikkal,” is more than 3,000 years old. But in a sense, our relationship with music is far more ancient than that.

As Michael Spitzer, a professor of music at the University of Liverpool, told Big Think, humans have been making and learning to recognize music from the moment our species learned to walk on two legs, creating a predictable beat.

Music affects the brain in profound ways. It eases stress by lowering cortisol. It floods the brain with pleasurable neurotransmitters like dopamine. And it serves as a conduit through which we can process emotions that otherwise might not be describable in words.

MICHAEL SPITZER: 4.4 million years ago, an Australopithecine called "Ardi" stood on her legs and walked. And ever since then, the rhythm of walking has stamped human music, but much more than that, pun intended, that the first steps put us on the path to forging links between the brain and muscular exertion and sound. Hominids learned to hear footsteps as a pattern- and what patterns give you is a sense of time. You can predict what will happen next, and it's willy-nilly reflecting the experience of walking through the Earth. The condition of being human- being midway between the birds in the heavens and the whales in the ocean- we can situate ourselves. Birdsong is as jerky as the motions of the bird. Just as whales have a much more fluid rhythm of floating through their own medium. Human music reflects walking, and this also gives humans their fascination with this metaphor that music moves. And if you think about it, music does not move, but we imagine that one note moves to the other. And most of music, be it a symphony or a song, unfolds a journey. And this journey takes us from one point to another. In our minds, it's an imaginary journey, a very long, distant echo from the journey of our ancestors out of Africa. 

What makes human music so distinctive is our link between sound and motion, which is due to the connections in the human brain between the motor regions controlling our motion, and the regions controlling hearing and sound, the auditory cortex. As a rule, the deeper you dive into the human brain, the more universal one's propensity for music and for emotion goes. If you start with the brainstem, our oldest layer, brainstems flinch to reflexes in sound. So shocks and loud bangs will trigger the brainstem reflex. The next layer up, the basal ganglia, responds to pleasure. Whether a sound is pleasant or unpleasant. The amygdala is where emotions happen: Sadness, happiness, anger, fear. And the most modern layer, the neocortex, is the point where you process patterns and the complexities of music. 

In terms of our music instinct, one of our faculties, which are inborn, is what's been called 'auditory scene analysis' or the 'cocktail party effect.' If you go to a party and you are surrounded by people jabbering away in different simultaneous conversations, you have an astonishing capacity to tune into a particular thread. It's the same faculty you have when you're listening to a line in a bar fugue or in a jazz standard. We can focus our listening. Birds also have that: Infant and a father Emperor penguin surrounded by 40,000 breeding pairs can hear each other's voice in this incredible hubbub. Appreciating music purely as a form of relaxation or entertainment does a massive disservice to all the things that music helps you with. The biggest draw to mental health is loneliness. Music can bring people together. You don't have to actively make music with somebody else, just to listen to music plugs you into a social network because every note of music is social- it's formed of social conventions. Music lowers stress by reducing cortisol, it gives you pleasure, makes you happy by flooding the brain with neurotransmitters like dopamine. Music is an excellent way of tagging memories, remembering the past- expressing your deepest emotions and your identity, which can't be captured by language, because music is far too precise for words. All these things increase your mental health and ultimately music becomes a mode of mindfulness, of contemplation. It's not purely relaxing because there's too much going on when you're listening. And the word relaxation gives a sense of passivity, whereas to listen is a very active and creative activity.

- 'And today, even the youngest children learn to toodle an instrument.'

SPITZER: We also love to imitate rhythm, and that's due to the existence of mirror neurons in our brains. When the brain sees an action, you don't have to move to experience that motion in your brain because the mirror neurons are responding sympathetically. We've always had an instinctive faculty to imitate. We call it 'mimesis.' Yawns are contagious. If I see you yawning, I yawn back. But also emotions are contagious. When I hear a sad song, my body, my mirror neurons are instinctively sympathizing, are mimicking, are mirroring. The sadness of the song isn't just acoustic, it's also encoding the behavior which we associate with sadness, which is grieving. Emotion isn't just feeling. Darwin was the first to observe that emotion had an adaptive role in the field: that animals and people, they experience emotions in relation to goals which help them survive. So happiness is when you achieve a goal. Anger is when the goal is blocked. Sadness is when you lose a loved one. Fear is the most archetypal emotion. When you are exposed to a threat, you have an instinctive response to either freeze or to fight or to flee. Music is full of similar responses, as an extreme reaction to music, which has been called "the chills," or 'frisson,' or the sublime. There are moments in music which are so intense and they're often triggered by breakthrough moments of loudness or extremity. You have the same parts of the brain which responds to that as responds to fear. Which is why the chills give you goosebumps or piloerection. The hairs on your skin literally stand on end. But you enjoy this fear. 

And this is very strange, and we have a similar experience when we go on a fairground ride or when we're watching a volcanic eruption in the safety of an observation platform. It's almost as if music is violence without the danger. Nobody dies in music: it's why we think that music is able to express emotion in a very visceral way. So when you are listening to music, it's a kind of mental time travel. When you are absorbed in the work, you are traveling back through layer upon layer of your brain, almost biologically, which is why I call music a sort of umbilical cord back to Mother Nature.