Inner Workings

Simple, monotonous beats aren’t really entertaining (try dancing to a metronome and see where that gets you). They have low levels of syncopation and certainly don’t make you want to dance. In contrast, chaotic and unpredictable music, like free jazz, has very high levels of syncopation and rarely, if ever, entices people to dance. Of course, some people will disagree with this, but then no matter how unpleasant/bizarre/unfathomable something is, you’ll find a human somewhere who likes it. They’re good like that, people are.

The middle ground (funk music like James Brown is the most referenced by the researchers, and is also what Professor Kringelbach danced to for our considerable enjoyment) hits the sweet spot between predictable and chaotic, for which the brain has a strong preference. Most modern pop falls somewhere within this range. This is likely why you can hate a modern pop song with a passion, openly declaring you detest every single thing about it, and still find you’re tapping your foot along with it when you hear it played in a shop.

The point is, for some reason, tunes that have a specific balance between predictability and chaos induce pleasure in our brains, making us happy to the point where we’re compelled to physically respond. Clearly the underlying processes by which our brains determine what makes us happy are not exactly straightforward. It’s not a simple yes/no matter of something making us happy, or not; often it’s a specific amount of something that makes us happy, and any more or less has the opposite effect. Think of it like salt; too little salt in your food, and it doesn’t taste nice. Too much salt in your food, and it doesn’t taste nice. The right amount of salt in your food, it tastes good, and the poor waiter can finally move on to the next table.

Here’s another weird finding; it might not even be our brain that determines our happiness, but our gut. While a number of clichés and sayings acknowledge links between our brains and digestive system (‘the way to a man’s heart is through his stomach’ or ‘I can’t think on an empty stomach’, and so forth) it might still be surprising to know there’s a lot of scientific evidence to suggest the workings of our gut could have a direct and profound impact on our mental state.

It’s important to remember that our stomach and intestines aren’t just simple wobbly tubes that the useful bits of food pass through; they’re incredibly sophisticated in their own right. As well as possessing a dedicated and intricate nervous system of its own (the enteric system, which can in some cases operate independently, hence it’s often labelled ‘the second brain’), our gut is also home to tens of trillions of bacteria, of thousands of different strains and types. All of these have potential roles to play in our digestion process, by determining the substances that enter our bloodstream and travel to every part of our body, potentially influencing the activity of every organ and tissue. Overall, it’s clear these bacteria have direct impacts on our internal state.

Remember, the brain, despite its sophistication and baffling complexity, is still an organ. It’s not just affected by the things we sense from the world outside our heads, it’s also beholden to what’s going on inside the body. Hormones, blood supply, oxygen levels, the countless other facets of human physiology: these all impact on the workings of the brain. Given that the gut (and the bacteria it’s home to) has a crucial role regarding what goes into the body, it’s perhaps to be expected that it would have significant, albeit indirect, influence over how the brain functions.

This is an extract from Dean Burnett's Happy Brain published by WW Norton & Company