WACO, Texas — It’s a common belief that some nice, soothing music at bedtime will help put anyone get to sleep. Although lullabies may be an age-old sleep remedy, a new study finds listening to music before bed can actually be harmful to your sleep quality. Researchers from Baylor University say those dreaded “earworms” don’t just annoy people throughout their days, they can also stick in your mind while you sleep.
Earworms, or involuntary musical imagery, are songs or tunes which keep replaying over and over in a person’s mind. While these annoying melodies usually happen during the day, the Baylor team discovered they keep triggering the brain while someone is unconscious.
“Our brains continue to process music even when none is playing, including apparently while we are asleep,” says associate professor of psychology and neuroscience Michael Scullin in a university release. “Everyone knows that music listening feels good. Adolescents and young adults routinely listen to music near bedtime. But sometimes you can have too much of a good thing. The more you listen to music, the more likely you are to catch an earworm that won’t go away at bedtime. When that happens, chances are your sleep is going to suffer.”
The study finds people who experience earworms at night more than once a week are six times more likely to have poor sleep quality. Interestingly, researchers say instrumental music appears to cause more earworms which disrupt sleep than lyrical music.
Earworms can keep someone up all night
Study authors used both a sleep survey and a lab experiment to explore music’s link to bad sleep. The team had 209 people complete several surveys gauging their sleep quality, music listening habits, and how often they experience earworms at bedtime. Researchers also asked how often these volunteers wake up at night and in the morning with a song already playing in their heads.
Next, the Baylor team studied 50 participants at Scullin’s Sleep Neuroscience and Cognition Laboratory. There, study authors tried to trigger an earworm to see how they directly affect sleep quality. Scientists used polysomnography, the gold standard in measuring sleep, to record each person’s brain waves, heart rate, and breathing while asleep.
“Before bedtime, we played three popular and catchy songs — Taylor Swift’s ‘Shake It Off,’ Carly Rae Jepsen’s ‘Call Me Maybe’ and Journey’s ‘Don’t Stop Believin’,” Scullin details. “We randomly assigned participants to listen to the original versions of those songs or the de-lyricized instrumental versions of the songs. Participants responded whether and when they experienced an earworm. Then we analyzed whether that impacted their nighttime sleep physiology. People who caught an earworm had greater difficulty falling asleep, more nighttime awakenings, and spent more time in light stages of sleep.”
By monitoring electrical activity in the brain, researchers also analyzed markers of sleep-dependent memory consolidation in the group. Memory consolidation is the process by which the brain reactivates temporary memories during sleep and turns them into long-term memories.
“We thought that people would have earworms at bedtime when they were trying to fall asleep, but we certainly didn’t know that people would report regularly waking up from sleep with an earworm. But we saw that in both the survey and experimental study,” Scullin reports.
How does music actually affect the brain?
Study results reveal that sleep earworms cause more slow oscillations during sleep, a sign of memory reactivation. Researchers add these changes more frequently occur in the primary auditory cortex of the brain. Scientists believe this region also has a link to processing earworms when people are awake.
“Almost everyone thought music improves their sleep, but we found those who listened to more music slept worse,” Scullin says. “What was really surprising was that instrumental music led to worse sleep quality — instrumental music leads to about twice as many earworms.”
Additionally, the surveys reveal people you listen to music more often typically experience more persistent earworms and greater declines in sleep quality. The new findings definitely don’t line up with the old theory that music can have a hypnotic effect on people at bedtime.
In fact, health experts commonly suggest listening to music before bed, but the Baylor team says these recommendations are generally based on results from self-reported studies. Study authors argue their findings objectively measure activity in the brain as it processes music for several hours. With that in mind, Scullin recommends that people who enjoy some tunes before sleep take breaks if an earworm begins to bother them. Overall, timing is key and listeners should try to avoid too much music right before going to bed.
“If you commonly pair listening to music while being in bed, then you’ll have that association where being in that context might trigger an earworm even when you’re not listening to music, such as when you’re trying to fall asleep,” the sleep researcher concludes.
The study appears in the journal Psychological Science.