For many people, music feels like a part of our subconscious. It’s constantly playing in the background, whether we’re at a coffee shop, in the elevator, working from home, or even just walking down the street. Every year, Spotify tells us how many minutes we’ve spent listening to music. I spent 53,402 minutes in 2021—17 hours a week—which is far more time than I’ve spent doing most other things. In 2017, Nielsen estimated that Americans spend over 32 hours a week on average listening to music. It’s no surprise that we have such a strong memory for music and can easily recall lyrics and melodies, even if we haven’t heard them in years.
In March, a new Wordle spinoff called Heardle launched. It tests musical memory by asking people to identify a song after hearing only one second of it, and for every wrong guess, extends the track by one second. I was excited to have a place to use my musical knowledge, and I’m not the only one. Millions of players have used Heardle to identify popular and nostalgic songs from different generations, from the Fugees to Spice Girls to Adele.
The popularity of Heardle taps into an interesting part of human psychology: how deeply we store music in memory and how easily we can recall it. “There is an approach called the gating paradigm [which is] very similar to the Heardle app,” says Dr. Kelly Jakubowski, assistant professor of music psychology at Durham University in the U.K. “You present one note [and then two, and then three to] see how long it takes people to identify a piece of music, so I think that it’s quite funny that they’ve kind of tapped on that [with Heardle].”
Manyof us can hear music in our minds, which is called having musical or auditory imagery. “This can happen voluntarily or deliberately, so if I [ask you to] think of the song ‘Happy Birthday,’ you can probably hear it playing in your mind right now, but it can also happen involuntarily. That’s what we call an earworm, when we get a song that pops into mind without you actually trying to recall any music,” Jakubowski says. It’s quite common to have a song stuck in your head—“around 90% of people say they have an earworm at least once a week and around ⅓ of people say they have an earworm at least once a day,” she notes. As you might imagine, people who listen to or engage with music more frequently tend to experience more earworms. The more we listen to music, the more it spontaneously comes to mind.
Apps like Heardle are satisfying to play because “when we perceive or imagine music that’s quite meaningful to us, we get activation in what we call the reward centers of our brain,” Jakubowski says. Listening to music releases dopamine in the brain, with our dopamine levels increasing by up to 9% when listening to music we enjoy. That’s one reason why music has become so intertwined with how we express and comfort ourselves.
“Music is inherently bound up with personal identity, and so [when people can] identify pieces of music without a lot of information, it’s often music from their youth [which can trigger] what we call the reminiscence bump in autobiographical memory,” Jakubowski says. “Older adults have a really good memory for certain songs from their youth because they listened to that same record over and over … It can bring back your memories from that time period when you were having these self-defining experiences.”
Listening to nostalgic pop music on Heardle can also have an emotional impact, because music triggers emotional responses. “Even if you’re just identifying a piece of music based on the first second of it, you have this musical imagery experience [that] probably triggers the memory of that whole piece of music, and then you have the emotions coming back associated with it,” Jakubowski says. “Musical imagery can elicit the same emotional responses as actually listening to a piece of music.”
When we listen to a song, we don’t just remember the music and lyrics—we also understand the emotions that are being conveyed. “Orienting yourself towards the emotional message actually helps you remember the actual music better,” says Dr. Andrea Halpern, professor of psychology at Bucknell University in Pennsylvania.
In a 2010 study published in Music Perception, Halpern and colleagues had musicians listen to the first minute of familiar classical pieces and record their judgments of the emotions they were hearing in the music through their valence and arousal. Then, the participants did the experiment again while just imagining the first minute of these songs playing in their minds. “The overlap in their profiles was astonishing, which means that they were doing this complicated piece in real time and extracting the same emotions,” Halpern says. The musicians were able to map the emotions expressed in the music even when it was playing in their heads and imagine the music so vividly that their scores were almost identical.
This shows that we can quite accurately recreate some aspects of music in our minds. “Imagining music is actually a very similar experience to perceiving music,” Jakubowski says. “There [are] very strong parallels in terms of the brain activation you see when you imagine music versus when you perceive music.”
Our memory for music may not be perfect, but it’s still quite impressive. In a 2015 study published in Memory and Cognition, Jakubowski, Halpern, and colleagues tracked the accuracy of our involuntary musical imagery to see how close our mental representations were compared to the actual music. Participants wore wristwatch accelerometers and, every time they had a song stuck in their head, tapped along to record the beat of the song. “We found that these participants, the vast majority of which were non-musicians, had quite accurate recall of musical tempo within involuntary musical imagery,” Jakubowski says. “[59%] of the earworms were within 10% of the original recorded tempo [which suggests that] even when people who don’t have a lot of formal training in music are spontaneously thinking of music in their everyday lives … it comes to mind quite accurately, at least in terms of tempo.”
Even if you aren’t a musician, you can still have an intuitive understanding of music from how often you experience it. “We don’t necessarily read our favorite book or watch our favorite film as many times as we listen to our favorite music,” Jakubowski says. “Even non-musicians have really accurate musical memory. It’s not that they are deliberately trying to memorize the piece of music, they’re just getting exposed so much that they become musical experts in a different sort of way just because of this incidental exposure to music [that’s] really prominent in our world today.”
People often wonder why we tend to remember songs and lyrics more easily than our own memories, where we kept our keys, and what we learned in school. It seems to be because of how often we experience music, in the world or in our minds, and the joy and emotional connection it brings us. Music represents who we are and how we feel, so of course it’s what we remember.
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