"Erm, what is it, that thing that you do?"
This is the question that follows the eyebrow V, that follows my response to the question, “what are you doing your PhD on?”.
Music neuroscientists. I can tell you what we do not do.
My nan is 89 years old. White hair, spectacled, unsteady on her feet these days. I went home to visit my family recently and sat down to talk to her about some of my research. I pulled out colourful fMRI images, diagrams of the brain; I pointed to the neural networks I find most exciting. Not surprisingly, this tutorial peaked my nan’s interest. My nan, you see, is a musician herself. A pianist. At a time when married women with children were expected to stay at home, my nan took herself off to the Conservatorium and pursued her love of music.
It has been some years now, however, since my nan has played the piano. Arthritis has not been kind to her clever fingers. Music is still in her, though. But not quite in the way she had considered. I should mention here that, earlier this year, my nan had a fall. She hit her head on the way down and was sent for routine neuroimaging. While the scans indicated nothing untoward, my nan had clearly spent some time pondering them. I say this because, as I showed her my colourful pictures, she asked, “in those scans that I had, could you see the music in my brain?”.
It is a beautiful thought, no? That the thing my nan found such joy in, the cadenzas and the appoggiaturas, the Tchaikovsky and the Bach, might somehow be pocketed in the crevices of that extraordinary brain jelly of hers?
Good to know. This is why:
Our brains are not for music.
Brains are a big old soup of things. In there, there are grey blobby bits and white stringy bits, fluid flowing through an aqueduct, blood running through arteries, and neurotransmitters for days. What this soup is, is a living organ. And, indeed, this living organ is our music translation device: vibrating air molecules transduced into neural signals in, our perception of music out. Music is the outcome of the brain doing its thing.
But so is every other thing we experience in every moment of our life. A sunset is not a sunset, for example, until the brain decides that it is. Put another way, brain tissue is not specialised for the perception of music. This can be appreciated when we consider that much the same neural machinery is required to experience music as would allow us to hear our name, feel warmth on our skin, or enjoy a square of chocolate. The brain is a multi-tasker. For this reason, look as hard as we might, we will never find a “musical lobe” or, indeed, a snippet of a symphony wedged within a synapse.
It is not the what that is interesting, it is the how.
We know that I can recall every word from every song of the Goo Goo Dolls’ “Dizzy Up the Girl” album because, thanks to my days as a 14-year-old, if you ask me, I can sing them for you. In this way, the what is of little consequence, simply because it can be deduced by behavioural observation. The what does not require a fancy scanner or an understanding of the brain. To get at the how, however, we need music neuroscience.
But what is the how?
So wonderfully innate is music that, if you are human, and you are born, chances are you have all the requisite machinery for a meaningful relationship with vibrating air molecules. Brilliant, no? Musical training may, of course, have an impact on how our capacity to process music develops. Small differences have been found between individuals who begin music lessons prior to 7 years old, and those who begin lessons later, for example. It is not yet clear, however, whether those small differences reflect a “neuroplastic effect of music”, or, less impressively, a trait which predisposes children to pursue or excel at music.
Regardless, musical training does an unremarkable job at accounting for individual differences in how we process and experience music. Consider that some musicians have absolute pitch, whilst others do not. Moreover, some musicians experience “chills”, whilst others do not. At best, musical training accounts for some of the why there are individual differences in how we process music. Culture and music listening habits also likely fall into this why category. And whilst the why of the how still falls in the domain of music neuroscience, in my opinion, the how is far more interesting.
By how, I am referring to the way individual brains bias incoming information. That is, there are networks in the brain which hone in on particular aspects of stimuli out there in the world. These networks weight those particular aspects with significance and, either campaign to make them centre-stage, or gate them the hell out. The result of processing information in this way, over a myriad of more-or-less communicating neural networks, is how we find ourselves instinctively responding to music. Importantly, understanding this process is not a task of “where’s Wally”, "who's Wally", or even "why is Wally there?", but a task of “how the hell did Wally get there in the first place?”.
The what is the easy part. The how is where the magic happens.
Music is everywhere.
Everywhere in the brain, that is. A decade-and-a-half of neuroimaging studies tell us that processing of music is distributed from neocortex to brainstem, from our most evolved systems to our most primitive. In this way, music has a beautiful capacity to “gather us up”. This beautiful capacity, however, makes searching for musical processing wildly impractical.
Music neuroscientists approach this problem by dissecting musical processing into smaller component functions. Music, you see, is a “multi-determined stimulus”. If we look at how the brain puts together music from the ground up, we can see it comprises building blocks which answer the questions, “what?” and “when?”. These building blocks include melody, harmony, rhythm, and tempo, among many others. Yet, the brain is not a diligent and objective stimulus processor. Cheeky monkey that it is, it draws on previous experience to make efficient (or lazy) inferences about incoming information. It “fills in the gaps”, so to speak. It also “flavours” music with its subjective interpretation. Thus, not only does musical processing comprise a pulling together of fundamental sound components, but it includes processes which project meaning onto those sounds based on prior experience and contextual cues, as well as inject emotional significance, such as sadness or pleasure.
So, music neuroscientists typically do not investigate how we process music as a whole, but how we process discrete aspects of it. This allows us to narrow down our anatomical investigations to a more manageable suspect line up. It also risks reducing music to a sum of its parts.
As most music listeners will intuitively tell us, we do not experience music as partitioned streams of melody, harmony, rhythm, and tempo. Rather, we experience music as a whole and integrated stimulus. Thus, music neuroscientists are faced with a weighty challenge: we must determine what components of musical processing might sensibly be dissected so as to allow for pragmatic investigation. But, at the same time, we must keep in mind the critical limitations of this methodology; how fundamentally dismantling musical processing may result in pieces that do not make sense anymore if we put them back together.
So, if I were to offer a piece of advice on how to be a music neuroscientist (and, believe me, I am still learning), it might be, in pursuing the how of it all, we would do well not to lose what it is we came to study. Let's not lose sight of the music.
I think my nan would whole-heartedly agree.