How harmful is music, really?

For a while, I thought music was harmful, due largely to pervasive and arbitrary earworms. More recently, I started to find that earworms are ephemeral and lawful. A contrarian belief held like the former for years gets stuck as part of my identity, but maybe I should find the truth.

You don't use science to show that you're right, you use science to become right.

— Randall Munroe

"Music is harmful" is hard to measure and verify. "Listening to music is harmful" is both easier to measure and more readily useful, for you can make a randomised controlled trial out of it.

§ Methods

Given that I deliberately listen to music only on rare occasion, it's easy, in my case, to let a column of random booleans in a spreadsheet dictate whether I listen to music each day. Sometimes I forgot to listen to music when the spreadsheet said I should, and sometimes I heard a lot of incidental music on days when the spreadsheet said I should abstain. To account for both cases, I kept a record of whether I actually did listen to music each day. Whether I actually listened to music is the explanatory variable, which ended up 50% correlated (phi coefficient) with whether the random boolean generator said I should.

The response variables are my mood — -1 to 1 — and the song stuck in my head — one of four categories:

• no song (N)
• a song played back deliberately (D)
• a song I heard recently (R)
• any other song (O)

Both response variables were queried by surprise, 0 to 23 times per day (median 6), constrained by convenience.

§ Analysis

I ran the experiment over 51 days. In all analysis here, I exclude three long intervals (11 days, 5 days, 4 days) of consecutive musical abstention due to outside constraints, leaving 31 days to examine.

Given these measurements, we can find the effects of listening to music by comparing the averages from days with music to those from days without music. It seems plausible that the effects of music lag or persist past the day of listening. Perhaps the better averages to compare would come from

• music days, plus days just after music days, versus
• all other days

What kind of harm do I expect to see from listening music?

• It could worsen my mood.
• It could make earworms play for more of the time, i.e. increase the ratio of D+R+O to N.
• It could make more of my earworms accidental, i.e. increase the ratio of R+O to N+D.
• It could make whatever particular music I listen to show up more often as accidental earworms, i.e. increase the ratio of R to O.

§ Results

What does my data say about all that?

It appears that listening to music, in the short-term:

1. makes me a tad happier
2. makes earworms play in my mind for slightly less of the time
3. makes accidental earworms (as contrasted with deliberate earworms, or mental quiet) play slightly less of the time
4. has a weak, ambiguous effect on which songs I get as accidental earworms

Result 1 makes sense, but deserved testing, just to be sure. Results 2 and 3 go against my intuition. I'm less sure what to make of result 4, especially given that it's harder to measure — judging an accidental earworm as "recent" depends on a threshold of recency, which I left ambiguous, and on my memory of what songs I've heard recently, which can mess up on occasion.

§ Applications

Listening to music is a small net positive. Perhaps I should do it more often, with caveats:

• If I listen to music too much, I may become dependent on it, as already seems to have happened to many others. I want to be able to live easily without it, in case I lose access to it, or later find again that it's harmful.
• The songs I listen to seem perhaps to dictate the songs that replay as earworms. So I should favour songs that I would tolerate more gladly as accidental earworms. To a first approximation, that means I should favour lyricless music, to keep the verbal parts of my mind free and fully-functional when I get earworms.