Some people feel music so strongly the sensations can be compared to sex. How does a good song move the body and mind in this way, asks David Robson.

Sometimes music strikes the body like a bolt of lightning. “I was in a friend’s dorm room in my third year as an undergraduate,” Psyche Loui remembers. “Rachmaninov’s Piano Concerto No. 2 came up on the radio and I was instantly captivated.” A chill down the spine, fluttering in her stomach, a racing heart – the musical movements still send the same feelings surging through her body to this day. “There are these slight melodic and harmonic twists in the second half that always get me!” she says.

The aesthetic experience can be so intense that you can’t do anything else

Loui is an accomplished pianist and violinist, but you don’t need to be an expert for a song or score to electrify the senses in this way; it can strike anyone, anytime – in a cathedral or a shopping mall, at a wedding or on the Tube. You may know these physical feelings as chills or tingles – but some people feel them so powerfully, they describe the sensations as “skin orgasms”. “The aesthetic experience can be so intense that you can’t do anything else,” says Loui.

We normally only respond like this to experiences that might ensure or endanger our survival – food, reproduction, or the terrifying plummet of a rollercoaster. How can music – hardly a life-or-death pursuit – move the mind and the body as powerfully as sex? Years after her first dalliance with Rachmaninov’s concerto, Loui became a psychologist at Wesleyan University, and recently reviewed the evidence and theories explaining the phenomenon with her student Luke Harrison.

Loui and Harrison point out that the sensations can be extraordinarily varied beyond the shivers people normally report. A 1991 study of professional musicians and non-musicians, for instance, found that around half of all the respondents experienced trembling, flushing and sweating, and sexual arousal in response to their favourite pieces, as well as that familiar feeling of a shiver down the spine. Such varied and potent experiences may explain the origins of the term “skin orgasm”, and indeed, many cultures openly recognise the similarities. North Indian and Pakistani Sufis have long discussed an erotic dimension to deep music listening. Even so, Loui and Harrison tend to prefer the term “frisson”, since it avoids embarrassing connotations for experimental subjects describing their experiences.

North Indian and Pakistani Sufis have long discussed an erotic dimension to deep music listening

As Loui has noticed herself with Rachmaninov’s concerto, people are often able to pick out specific measures that release an outpouring of those sensations. Using those reports, researchers have then been able to pinpoint the kinds of features that are more likely to trigger the different sensations during a musical frisson. Sudden changes in harmony, dynamic leaps (from soft to loud), and melodic appoggiaturas (dissonant notes that clash with the main melody, like you’ll find in Adele’s Someone Like You) seem to be particularly powerful. “Musical frisson elicit a physiological change that’s locked to a particular point in the music,” says Loui. Our YouTube playlist below offers you some of the songs that seemed to elicit the most skin orgasms in lab subjects.

By asking subjects to listen to their favourite tracks while laying in an fMRI scanner, neuroscientists have then been able to map the regions of the brain that respond to chill-inducing tracks – helping them to chart some of the mechanisms that may correspond to this peculiar phenomenon. (See BBC iWonder’s interactive graphic of the brain’s response to musical tingles.)

Sweet anticipation

One major component seems to be the way the brain monitors our expectations, says Loui. From the moment we are born (and possibly before), we begin to learn certain rules that characterise the way songs are composed. If a song follows the conventions too closely, it is bland and fails to capture our attention; if it breaks the patterns too much, it sounds like noise. But when composers straddle the boundary between the familiar and unfamiliar, playing with your expectations using unpredictable flourishes (like appoggiaturas or sweeping harmonic changes), they hit a sweet spot that pleasantly teases the brain, and this may produce a frisson.

You see a similar response when people take drugs or have sex, which may explain why we find shiver-inducing songs so addictive.

For instance, violated expectations seem to startle (albeit gently) the automatic nervous system, in its most primitive region, the brain stem - producing the racing heart, the breathlessness, the flush that can signal the onset of a frisson. What’s more, the anticipation, violation, and resolution of our expectations triggers the release of dopamine in two key regions – the caudate and the nucleus accumbens, shortly before and just after the frisson. You see a similar response when people take drugs or have sex, which may explain why we find shiver-inducing songs so addictive, says Loui. (Along similar lines, when pharmacologist Avram Goldstein at Stanford University blocked the brain’s opiate signalling - a system that controls reward and addiction - he found that it significantly reduced volunteers' ability to feel skin orgasms.)

Once you get to know a song, these feelings may become even more powerful. Even though you have lost the initial sense of surprise, you may have become conditioned to feel the frisson – just like Pavlov’s dogs salivating when the bell rang for their food.

On top of all this, a favourite piece of music will speak to our empathy as we try to imagine what the composer or singer was feeling. It will also evoke our memories as the song becomes entrenched in the central events of our lives. The result is a heady emotional cocktail whenever you listen to the piece – and it is partly why our taste is so individual, says Loui. “Our own autobiographical experiences interact with the musical devices – so that everyone finds a different piece of music rewarding.”

You could put skin orgasms in the same bracket as cocaine, or masturbation: pleasurable experiences that have come to hijack machinery for more basic human needs

These insights are particularly interesting, when you consider the evolution of music. Some experts, such as the cognitive scientist Steven Pinker, have argued that music simply piggybacks on other cognitive machinery – such as a penchant for pattern recognition – that evolved for other, more important functions. It is, he says, no more than “auditory cheesecake”. “It’s that idea that music sure is yummy, but it’s not very nutritious,” explains Loui. In this sense, you could put skin orgasms in the same bracket as cocaine highs, or masturbation to pornography: pleasurable activities that just happen to hijack the brain’s responses to more basic human needs.

Loui, however, doesn’t subscribe to Pinker’s idea. Instead, she tends to prefer the idea that music is a “transformative tool” that helped us build the human mind and further society. Think of it as a kind of sandbox, she says. After we have performed all the most important duties to survive, we use music as an arena to play safely, train our minds and expand our experiences. During that playtime, we also use it to develop our emotional awareness, and to bond with others. “You don’t play alone in sandboxes but with other people,” she says. Music may have also helped us exercise our emotional communication.

If that’s the case, musical frisson could be our reward for exercising our minds and our societies in this way. There is no hard evidence, but Loui is intrigued by recent studies showing that the denser the wiring between the auditory, social and emotional parts of the brain, the more skin orgasms you feel. That could, perhaps, be a neurological signature of music’s social importance. Others have found that making music and dancing together produces more altruistic and cohesive groups, with one study finding that chill-inducing music is particularly good at promoting altruism in the lab’s subjects. Maybe it is the rush of endorphins from a skin orgasm that helps promote the communal goodwill.

These are just evolutionary just-so stories, of course. We may never truly understand why music first emerged. But even if it is just a form of auditory cheesecake, it is a legal high we could ill afford to live without today: it defines us, our friendships and offers a soundtrack to the most important moments in our lives. The fact it tickles the same pleasure centres as cocaine helps underline all these benefits, and means we will always keep coming back for more. As Loui herself might agree: who needs sex and drugs when you’ve got Rachmaninov?

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