I’ve always been more puzzled than offended by the sight of runners and joggers equipped with portable music players and headphones or ear buds, bouncing down the street or circling a track while drawing inspiration from a playlist of their favorite tunes. It’s not that I object to listening to music in the background when working or working out — I’m actually listening to music as I write this — it’s that, for me at least, the act of running uniquely generates its own rhythms and emotions; adding external accompaniment seems superfluous, if not downright irritating. Even with the ability to access the world’s digital music library from anywhere and at any time, I stubbornly cling to the belief that some activities are better without a soundtrack.

But I’ve also long been aware that, without any assistance from modern technology, music enters into my running mind all the time. It bubbles up mysteriously from subconscious processes that are shaped by my mood, my surroundings, my level of effort, and the normal everyday events of my life. I’ll be in the middle of a run, and all of a sudden some fragment of music, perhaps a refrain from a popular song, appears and becomes stuck in my head, repeating itself over and over as I try in vain to think about something else.

It’s not always unpleasant. Depending on the music, it can even be enjoyable.

One of my first experiences with internal Muzak was, indeed, quite pleasurable. Many years ago before even 8-track and cassette tapes started us all down the road to highly portable music storage, I acquired a vinyl album with selected works by J.S. Bach, which, if memory serves, had the cheerful title “Bach’s Greatest Hits.” One of the tracks on the album was “Jesu Joy of Man’s Desiring,” and, like everyone else who has ever heard it, I loved that music. In case you can’t immediately recall it to mind, the music sets its sacred text to a lovely accompaniment that skips along in 9/8 time. That steady stream of sublime eighth-notes turned out to be an ideal rhythm to soothe the imagination of a sixteen-year-old kid traversing the quiet country roads of Amherst and Hadley while taking approximately 165 steps per minute.

I wish all of my internal music was so classy and refined as Bach, but actually I have little say in what my brain chooses to play. The other day I was doing a long run, and for some reason, I couldn’t get Michael Jackson’s “Billy Jean” out of my head, or rather, those few bars of the chorus that kept repeating. The more I ran and the more mental fatigue I accumulated, the shorter and sillier the fragments became.

Perhaps there is a connection between extreme physical distress and maniacal brain-music.

In the movie adaptation of “Touching the Void” (Joe Simpson’s unforgettable story of an almost fatal mountaineering accident), Simpson describes how, near death after days alone on the mountain, he can’t stop his brain from torturing him with the lyrics to the Boney M song “Brown girl in the ring”:

Brown girl in the ring
Tra la la la la
There’s a brown girl in the ring
Tra la la la la la
Brown girl in the ring
Tra la la la la
She looks like a sugar in a plum plum plum

In “Once A Runner,” John L. Parker describes a similar thing happening to Quentin Cassidy, as he struggles through the final throes of his appalling workout of sixty quarters. As he descends into Hell, Cassidy gets Beethoven’s “Fur Elise” stuck in his head, and by the end, he is full of exhausted self-pity:

Für Elise cranked up again and he wished it would go away. He hardly felt anything now. He hardly cared. Für Elise degenerated into a kind of steam Calliope gone haywire. Misplaced notes made what had been haunting, ugly; what had been precise and logical, mad and horrifying.

As if to keep pace with the crumbling music, his form occasionally broke and an elbow would flap out wildly, a knee would catch its brother instead of sliding by. Poor Elise, he thought. Poor everyone.

And then there are the times, rare in my experience, when my musical memory and imagination act as wise and comforting voices, counselors with deep insights about what at the time seem to be overwhelming problems. Running close to tears after some tragic or embarrassing mistake, my brain will reach down and find songs of sympathy and consolation. You never really get close to a sad song until you need it, and when you’ve taken it with you on an hour-long run in the rain.

Once or twice while running in a troubled state, my brain has searched the music library and come up empty, but instead of giving up, has composed its own healing music, no longer content to replay songs from the public jukebox. I’ll never forget once grief-stricken run along the California coast that produced an entire song that somehow acted as a real-life patronus charm, dissolving my dark thoughts like the mid-morning sun dissolves early mist.

So when I see people running and listening to their iDevices, I’m not offended at all, I’m just curious. What music would they hear, I wonder, if they pulled out the ear buds and let their brains choose the tune?