Today, we’ll be continuing our discussion of Daniel J. Levitin’s “This Is Your Brain On Music” once again. I’d say at this point, we’re about halfway through the book. So if you’ve been with us so far, great job! Halfway points are the only times when I’ll listen to Bon Jovi anymore (“Livin’ On A Prayer”), and even then, it’s mostly just in my head.
Last time, we went through Chapter 5, and discussed how the brain categorizes music. We talked about how musical memories differ from others, how a song can trigger memories from our pasts, and how expectations and emotions fit in.
Today, we’ll take a closer look at how music triggers emotions, and what it has to do with the cerebellum (popularly called the “reptilian brain”).
Last time, we mentioned that the cerebellum and the amygdala both play a large role in memory retrieval and emotional response. We also touched a bit on our expectations when we listen to music, and how that plays into our emotions. I’m only reiterating this so that we’re all on the same page. In this chapter, Levitin digs a little deeper.
“Metrical extraction, knowing what the pulse is and when we expect it to occur, is a crucial part of musical emotion. Music communicates to us emotionally through systemic violations of expectations” (p. 172).
We know this intuitively. Without variations, or violations of expectations, we judge a song as too robotic, or emotionally flat.
The Reptilian Brain
So where does the cerebellum come in? Well, when we listen to music, the cerebellum is what tracks the beat for us, and sets up our expectations. Levitin states that, “the cerebellum contains massive connections to emotional centers of the brain — the amygdala, which is involved in remembering emotional events, and the frontal lobe, the part of the brain involved in planning and impulse control” (p.175).
The cerebellum is also closely related to motivation. “Emotions for our ancient hominid ancestors were a neurochemical state that served to motivate us to act, generally for survival purposes” (p. 183). When we feel fear, the survival mechanism kicks in, and we know it’s time to run, or fight.
Due to the pressing need of surviving in a dangerous world, our perceptual systems are equipped to detect changes in our environment that could be threatening. When we determine a sound to be nonthreatening, it quickly recedes into the background, like the sound of a fan, or the hum of a refrigerator. Likewise, when we listen to music, the beat has a tendency to recede into the background when we hear melodic variations.
But none of this still explains why we sometimes experience intense joy and pleasure from listening to music. There’s still one more region of the brain involved for this crucial role.
The Reward System
The reward system of our brain is connected with the release of dopamine, and why it can be so hard to stop playing those stupid games on our phones, or scroll endlessly through status updates and tweets. The brain region associated with this is called the ventrial striatum. But, more specifically, it includes the nucleus accumbens.
“The nucleus accumbens is the center of the brain’s reward system, playing an important role in pleasure and addiction” (p. 189). This is the final piece of the puzzle.
“The rewarding and reinforcing aspects of music seem, then, to be mediated by increasing dopamine levels in the nucleus accumbens, and by the cerebellum’s contribution to regulating emotion through its connections to the frontal lobe and the limbic system” (p.191).
From this chapter, we can begin to see how it all fits together. In a way, hearing musical variations gives us a similar response to when we hear a joke.
Take the oldest joke in the world: peek-a-boo, the first one we all learn. Mom covers her face, the baby cries. The baby’s fear system is activated, and it’s doing the only thing it can do to survive. When Mom reveals she’s still there, the baby lets out a startled shriek that becomes laughter. The perceived threat was not actually a threat.
And so we experience intense joy when we sense a change that could signal a threat, but leaves us safe in the end. Levitin makes a note of this, too. He says that the brain “takes delight when a skillful musician violates the expectations in an interesting way”. He also notes that the “cerebellum finds pleasure in adjusting itself to stay synchronized”. Something to keep in mind the next time you’re listening to your favorite song.
Next time, we’ll look at what exactly makes a musician, as Levitin takes us through Chapter 7: Expertise Dissected.