By Sarah Berry
February 4, 2020
The sound of your alarm clock may determine whether you wake up in the morning feeling groggy or fresh, a small new study has found.
Standard alarm clock sounds (‘beep, beep, beep’) were associated with increased grogginess among participants while melodic sounds (The Beach Boys Good Vibrations or The Cure’s Close to Me, for example) were associated with increased alertness.
Grogginess, or its technical term, sleep inertia, is what happens as our bodies adjust from a sleep state to being fully conscious.
“In that period we have declines in our reaction times, in our thought process, in our attention and it can last up to four hours after waking,” explained lead author, RMIT doctoral researcher Stuart McFarlane.
“If you think about that in terms of the varied activities people do after waking you start to find it’s a potentially very serious area.”
One retrospective military analysis of more than 400 US Air Force accidents attributed to pilot error found that they typically occurred during the first hour after waking.
Maybe the reason you’re waking up on the wrong side of the bed has something to do with your alarm, not your sleep.
Waking from a deep sleep, after not enough sleep or, as is common for shift workers, waking in the night are all associated with increased sleep inertia. For the new study, published in the journal Plos One, McFarlane wanted to understand how the sounds many of us wake up to might also impact sleep inertia.
“A large portion of the population, particularly in the Western world do use sound to wake up so we thought it would be very interesting to see what effect sound may have on waking,” McFarlane said.
McFarlane asked 50 participants about the attributes of their preferred waking sound, including whether the pitch was high or low and whether the sound was melodic or monotonous. They were also asked about their feeling towards the waking sound, and to rate their perceived sleep inertia immediately after waking.
The participants’ feelings about the sounds they woke to, which ranged from popular music to talk-back radio, standard alarm sounds and nature sounds, made no difference, but there was a “significant relationship” between the type of sound and the perceived sleep inertia.
“People who reported less to zero sleep inertia also reported melodic waking sounds,” McFarlane revealed, adding that more monotonous and repetitive sounds, like a standard alarm tone, were significantly associated with increased sleep inertia.
“Melodies are essentially a collection of tones that rise and fall over a period of time,” McFarlane said. “What we’re hypothesising is that the rise and fall in tones and the way they are constructed as a piece or short vignette, may create or promote arousal within our brain and hence promote alertness and cognition rather than having this static approach of sound.”
He added: “The first component to an alarm is arousing someone so they wake up but that does not say how it affects them for 30 minutes or four hours afterwards in terms of cognition. And that’s what we’re looking at.”
While he said a “popular and really common” notion is that frightening someone with a loud sound will wake them up quickly, it also causes anxiety and this may lead to confusion upon waking, disrupting the brain’s ability to feel fresh and focused.
“We think that a harsh ‘beep beep beep’ might work to disrupt or confuse our brain activity when waking, while a more melodic sound like the Beach Boys ‘Good Vibrations’ or The Cure’s ‘Close to Me’ may help us transition to a waking state in a more effective way,” McFarlane said.
Better understanding the extent to which sound affects sleep inertia and how to use it to reduce the effect will be the subject of future research.