Tuesday, 25 June 2024
Earworms as an excuse to talk about mental simulations and working memory
This week I’d like to talk about an intriguing phenomenon: earworms, those bits of songs that start playing in your head for hours and sometimes even days on end. More specifically, I’d like to talk about a comment that biologist John Medina makes about earworms in an entry entitled “As the Worm Turns” in his substack “John Medina’s Brain Rules”. I call it a comment because, as Medina admits right off, no one really knows much about what causes earworms. But the two neurological considerations that he raises are still interesting. They relate to two key concepts that I of course discuss on my website: mental simulation and working memory.
As Medina relates, when experimenters used functional magnetic resonance imaging (fMRI) to scan subjects’ brains while playing certain well known tunes for them, their auditory cortexes showed up as activated in the scans. And when the researchers suddenly stopped playing the music but told the subjects to start imagining the next parts of the songs, their auditory cortexes were activated again in much the same way.
There’s nothing surprising about any of this today, when we know that the brain’s sensory and motor areas are invariably recruited in the process of mental simulation. But it would probably have seemed quite surprising to scientists in the late 20th century, when they swam in a sea of cognitivist metaphors that equated thinking and imagining with manipulating abstract symbols, and hence with activating high-level associative areas in the brain, rather than sensory or motor areas. Since then, however, scientists have realized that our thinking is “embodied”— in other words, that it is grounded far more deeply in our sensorimotor functions than was once thought.
The second point that Medina makes is that in the case of earworms, the brain network that is activated is the one associated with working memory—the buffer where a few items are normally stored for a few seconds and then vanish. Except, it seems, in the case of earworms, in which a subset of brain regions constitute the phonological loop— a circuit where earworms reverberate for an unusually long time. Why? For now, no one seems to have the least idea, except that earworms are usually simple, catchy tunes.
As for how to get rid of earworms, let’s just say that they will go away eventually, and that singing another song in your head can sometimes help, unless it turns into an earworm too!
Memory and the Brain | Comments Closed
