We’ve hit that time of the year when Christmas music is everywhere. Nearly two weeks before Thanksgiving, more than a dozen radio stations had already started playing a constant rotation of holiday music. Walgreens and CVS employees experience a nonstop barrage of Christmas songs on repeat. In the UK, you can’t pass an hour without being assailed by the strains of Slade’s “Merry Christmas Everybody.” If it all begins to feel a bit maddening, you’re not imagining it.

Psychologist Linda Blair says that the endless loop of Christmas music can actually take a toll on our mental health. That’s true for a lot of us, but especially for those who work in environments where blaring Christmas music is the perpetual soundtrack to their workday.

"People working in the shops at Christmas have to learn how to tune out Christmas music, because if they don't, it really does stop you from being able to focus on anything else," Blair said in an interview with Sky News. "You're simply spending all of your energy trying not to hear what you're hearing."

In fact, one quarter of retail workers in the US and UK say they feel “less festive” as a result of being forced to hear Christmas music all day long, according to a study by Spotify-owned Soundtrack Your Brand. One in six said all that Christmas music actually “dampens their emotional well-being.”

“Feeling less festive is a specific mental reaction to listening to Christmas music and rebelling against it, whereas the data showing it can have a negative effect on worker wellbeing must be treated with much more caution,” Soundtrack Your Brand founder Ola Sars told the New York Post. “In what can be a highly stressful job at this time of year, it’s important to consider whether a store’s soundtrack is actually increasing stress among its staff.”

There’s a direct and fairly predictable correlation between enjoyment of music and the frequency with which it’s heard. Music researchers have found that even if you like a song, your contentmentment with it peaks at a certain point. Too much play yields diminishing returns and a tendency to like the song less and less. The pattern fits the shape of an upside-down U.

The holiday season seems to kick off earlier each year, with Christmas music becoming pervasive in some stores even before Halloween. According to a study by the Tampa Bay Times, Best Buy outlets flipped to a nonstop Christmas shopping soundtrack on October 22. Sears/Kmart, H&M and Walmart started with the festive music in early to mid-November. Footlocker, Dunkin Donuts and Nordstrom all had the decency to wait until Thanksgiving before assailing shoppers with constant Christmas songs.

Fifty-six percent of American shoppers said they actually enjoy being trailed through store aisles by a Christmas playlist, though nearly a quarter said they don’t want to hear holiday songs before December 1. And while Christmas music can be soul-crushing for store employees who can't escape it, the sounds can be good for business: a 2003 study found that the right balance of Christmas-oriented smells and sounds makes shoppers feel good about their surroundings. Capitalism, do your thing.

Expect more Christmas music than ever this year, as more artists churn out holiday songs, which inevitably sell. And radio stations will keep the Christmas songs playing until December 26.

“It’s become like our Super Bowl,” Jim Loftus, CEO of 101.1 FM in Philadelphia told the OC Register. “Our audience almost doubles.”

“Christmas music is like the gingerbread latte,” Kenny King, program director at WASH-FM told the outlet.“It’s here for a limited time only, and it’s extremely popular.”