Ask a scientist what music is and they'll tell you that music is sound and that technically speaking,  sound is just waves of pressure being transmitted through air, water, or some kind of solid material. And that basically, music is just more of those same vibrations but arranged in very specific patterns. The sound of an electric drill, a barking dog, and an orchestra are all really just vibrations. But you've probably never been overcome by emotion when listening to an electric drill. So, why does music make us experience so many emotions?

To answer this question, let's first try to imagine the world without music. Canadian-born psychologist, linguist, and popular science author Steven Pinker once said that compared to vision or language, music could disappear completely and the rest of our lifestyle would remain unchanged. But music hasn't disappeared. Why not? Could there be some evolutionary advantage to having music?


Pinker says no. He calls music 'auditory cheesecake', meaning that we didn't evolve to love cheesecake specifically, but instead our ancestors learned to love anything sweet, high calorie, or high fat that they could find. So, whereas cheesecake may be nice, it was not the driving force behind our evolution. Pinker goes on to say that music is more like a side effect of language and our response to sounds like crying, laughing, shouting and growling.


Not everyone agrees with the cheesecake theory.

Music stimulates just about every region of our brain, including the neurological pathways that fuel our cravings for things like alcohol, nicotine and cocaine. Nobody has to teach a baby to move to a beat, they just do it. Nobody ever taught us that music can sound happy or sad. We just know that it does.


Some neuroscientists now think that music shares the same qualities as human movement. Remember the last time you found yourself tapping your foot or clicking your fingers to the beat of a song? That's music and movement together. One way we gained an evolutionary advantage over other species was simply by being social beings. Whether it's military marches, a lullaby, or a rock concert, nothing binds people together quite like music does.


But how do we get emotion from simple vibrations? Thalia Wheatley, a neuroscientist from Dartmouth College, carried out an experiment that suggested we sense emotion in music much the same way we sense emotion in human movement. She gave half of the participants of the experiment simple controls that could create either an animation of a bouncing ball and the other half controls that could create melodies. Using emotions as a guide, they operated the controls to match those emotions. Then they swapped over the controls.


The results were fascinating.

For each emotion they tested, the results for the melody were the same as for the bouncing ball. Happy bouncing balls shared the very same controls as happy music. The same applied to sad, angry, and peaceful. So, Wheatley's work demonstrates that emotion in music and movement seem to use the same patterns. And it's not just because of pop-cultural norms that have been reinforced in our society for centuries. Wheatley performed the same experiment in a culturally isolated village in Cambodia, and they found out that the melodies and movements were almost exactly the same as those recorded by the US college students from the first experiment.


Okay, so this might just be a tiny step on the path to figuring out why music can create so many feelings, but the experiment does show that music and movement go together on a much deeper level than moves on a dance floor. Just like we can sense someone is sad simply by watching them walk down the street, and we can always recognise a happy dance when we see one.


Music seems to move us because we move.

Our connection to music overlaps with movement because even though they run on different programs in our brains, they both use the same hardware, and it's these programs that make it so great to be human.


One thing we do know is that when we listen to a sad song a chemical reaction takes place in our brains. Research has shown that our brainwaves resonate with the beat of music, and that impacts our breathing and our heartbeat which try to match the beat of the song. This only happens to two kinds of animals on the planet, humans and songbirds. Which means, on some fundamental level, we are wired to respond to music.


It has been shown that listening to pleasant music boosts our serotonin, the brain chemical responsible for good feelings (and regular bowel movements, go figure!). Processing music is one of the few daily activities that we regularly participate in that involves both hemispheres of the brain. Each of us has a dominant hemisphere, left brain, right brain, but people who study music tend to use both hemispheres of their brain more. This generally makes them better at lateral thinking and creative problem-solving.


Listening to music also engages the hippocampus, the part of the brain which handles long-term memory storage. This is probably why listening to old songs can sometimes bring back memories that we thought we'd forgotten. Even someone with Alzheimer's and dementia can recover lost memories by listening to music.


But there are downsides too.

For instance, have you ever made a silly decision at a night club? Maybe in terms of making new friends, perhaps? Listening to sounds at volumes over 95 decibels can actually reduce our mental and physical reaction times by 20%. And club music usually plays at around 120 decibels. Loud music can actually increase the effects of alcohol. But you probably already knew that, right? What is amazing is that music works on a real, physical level. It affects our brain chemistry and body functions. But we still don't know exactly why. Music therapy is a field of study that has popped up recently to research and document these connections, but also to explore music as a possible painkiller or even as a way to cure addiction.