Your music preferences are built from the songs you listened to when you were young, the unique vibrations of your skull and even how your brain waves groove along. All this helps determine when and whether you prefer to bop your head to the latest pop tune, stick to old classics or seek out something stimulatingly different.
Researchers have tried to figure out why we like what we like by breaking down music into its parts, too, and there does to be a sort of universal preference for consonant chords over dissonant ones. But new research shows that as we age, the sometimes wince-inducing quality of dissonance may fade.
When played in context—say, in the roughness of a rock song—dissonance and consonance work together to give the song emotion. Still, people apparently dislike dissonance on its own. Philip Ball for Nature News writes:
Those preferences seem to stem from the so-called harmonicity of consonant intervals. Notes contain many overtones — frequencies that are whole-number multiples of the basic frequency in the note. For consonant intervals the overtones of the two notes tend to coincide as whole-number multiples, whereas for dissonant intervals this is no longer the case: they look more like the irregular overtones for sounds that are ‘inharmonic’, such as metal being struck.
A group of researchers led by Oliver Bones, of the Chinese University of Hong Kong, and Christopher Plack, of the University of Manchester in England, decided to further investigate consonance, dissonance and how our perceptions of them change with age. They asked 28 people under 40 years old and 16 over 40 to rank pairs of notes on their pleasantness or unpleasantness, reports Bethany Brookshire for Science News. The research team also recording their neural activity while the participants heard the notes.
They found that the younger people had distinct differences in the timing of their neuronal firing in response to dissonant and consonant chords. This difference grew less pronounced in older people. The researchers published their work in the Journal of Neuroscience. Brookshire writes how this aging process might affect how we hear music:
Even though these dissonant tones might seem unpleasant for young folks, Bones notes we probably can’t really enjoy music without them. He explains that we know a chord is dissonant only because it sounds different in comparison to a consonant chord. And that if you don’t have a perfect fifth to compare to a minor second, neither chord would sound as interesting — or, possibly, as musical. “If you didn’t have a sense of consonance you wouldn’t enjoy the dissonance,” he says. “It’s not that one is better.”
The results show that age-related hearing loss goes deeper than the loss of the hair cells in the inner ear. “As we age and temporal coding in the brain declines, this might be the cause of older listeners being less sensitive to the difference between consonant and dissonant chords,” says Nina Kraus, an auditory neuroscientist at Northwestern University in Evanston, Ill. She says a deterioration in the ability to distinguish these chords “might lead also to older listeners tending to engage less with music.”
So even if the older listeners found the dissonant chords less jarring, they may not be able to appreciate the chords effect in music. Instead of a piece that soars between sublime, dread and all the emotions in between, the music may be less moving.
Fortunately, the favorites from younger years will likely keep inspiring, as much due to memories as the notes themselves.