A few weeks ago, I caught the bus, and before I even sat down, I started rummaging in my backpack for my earbuds. After tipping the bag’s contents out on my lap in an increasingly frantic state, I realized: I must have left them behind. I had a 50-minute bus ride ahead of me, plus a 20-minute walk home, and I couldn’t remember the last time I’d spent that long in idle silence, without the dulcet tones of a favorite podcast to entertain me. I seriously considered an Uber, just to avoid being alone with my thoughts.
I first started listening to podcasts about four years ago, and since then they’ve become an integral part of my daily routine. I listen while I’m traveling, commuting, working, cooking, cleaning, and sometimes even while I’m showering. The only times I resign myself to silence are when I’m writing and sleeping. It’s a conscious effort to make the most of every available opportunity to cram more information into my brain, and I’m grateful for it; I’ve learned so much over the years thanks to my podcast obsession. And yet something about my panic over a silent commute home concerned me. It was like I couldn’t remember how to exist in the world on my own, without a stranger chattering into my ears at all times.
Podcasts have increased in popularity at an extraordinary rate since the success of Serial in 2014. Research last year showed that more than a third of all Americans had listened to podcasts, and of those who listened on a weekly basis, 36 percent listened to them between three and ten hours per week, with a further 12 percent listening to ten hours or more. I probably listen to about five hours a day on average, which means I’m consuming a somewhat staggering 35 hours of audio content a week. Listening to podcasts is basically my part-time job. But to fit all of that in, it’s not like I’ve stopped watching TV or movies or YouTube videos. I also still read books and skim through articles online all day long, and I continue to spend more time than is probably advisable scrolling through social media.
In other words, podcasts haven’t taken the place of other media consumption habits. Instead, they fill up the space in between, when I used to listen to music, or even simply let my mind wander in silence. I’ve even got my boyfriend into the habit of listening with me, and these days our quality time usually comes with a third wheel: a podcaster in the background, joking about politics or rambling on about some obscure historical facts.
Lately, though, I think I’m starting to miss peace and quiet. I’m also starting to wonder: What is my podcast habit doing to my brain? And is it even possible to memorize 35 hours’ worth of fun facts each week?
Research has suggested, after all, that silence is beneficial to cell development in the hippocampus, the brain region central to memory, emotion, and the nervous system. While these studies don’t specifically look at the difference between white noise, music, and spoken content, saturating our minds with information in audio form could be just as problematic as spending every waking hour consuming any other kind of media.
Because even though it feels like I’m making the most of my time by cleaning the house or commuting to a soundtrack of, say, heartfelt stories about the human experience via This American Life, it’s possible that I’m doing my brain a disservice by allowing it such little free time, explains Michael Grabowski, a professor of communication at Manhattan College in New York, who specializes in neuroscience and the human brain. “Consuming information is just the beginning — our minds need time to absorb and synthesize that information, to critically examine it,” he said. “That’s something that we do in silence, by actively disengaging from digital technology and focusing on the physical world around us.”
While most of us understand that spending hours of our time watching reality TV or completing BuzzFeed quizzes is probably not doing great things for our minds, podcasts are perceived as a more intellectual form of entertainment. Kara Silverman, a 34-year-old publicist based in Brooklyn and a fellow podcast devotee, tells me she listens to podcasts whenever her brain is not otherwise engaged by work or socializing. “To me, watching TV or YouTube videos is like the media equivalent of junk food, something I do for mindless entertainment to switch my brain off,” she said. “Podcasts feel like a way to educate myself, a positive use of my time, so I don’t really think about the possibility that I’m spending too long listening.”
And there is some truth to this assumption Silverman and I share. Podcasting is typically focused on nonfiction, educational content. As I’m writing this, the No. 1 podcast on iTunes is the New York Times’ weekday show The Daily, about current affairs. The top ten include NPR’s Rough Translation, about international news, Crooked Media’s Pod Save America, about U.S. politics, and general interest documentary-style shows such as Malcolm Gladwell’s Revisionist History and Stuff You Should Know.
Likewise, it also appears to be true that this type of media is indeed engaging our brains. Last year, in a rather meta episode of the Freakonomics podcast, Jack Gallant, a computational and cognitive neuroscientist from UC Berkeley, explains a study he was involved in, where subjects were put in an MRI and played episodes of The Moth Radio Hour, while scientists observed the effects on the brain. They found that when listening to audio content, the brain is working much harder than scientists had previously assumed. It isn’t clear, as Gallant explained during that episode, whether that increased activity is necessarily good for your brain. But what does seem clear is that the reason why podcasts excite our brains is likely the same reason why they became popular in the first place: They’re stories.
“One of the problems you have in MRI experiments is oftentimes they are very boring,” Gallant said on Freakonomics. “If you put somebody in an MRI scanner, which is a very uncomfortable place to be, and then you flash a word at them every five seconds for an hour, they get bored out of their skull.” The Moth’s stories, in contrast, are much more engaging. “You get lost in the stories,” he said. And when you listen to a podcast, it’s not just the part of your brain that processes sound and language that’s engaged. If you’re listening to a story that involves, for example, a pack of four barking dogs, one of which smells really bad, the part of your brain that is linked to your sense of smell, as well as the part that is associated with numbers and math, will be highly engaged. Listening to podcasts, in other words, is not a passive activity.
“They make your brain hum,” Gallant told Freakonomics. “Whether that humming is mysterious and delightful kind of depends on whether you wanted your brain to hum or not. If you were planning to sleep, that might not be so good.” Our brains need to work extremely hard to take just an audio input and turn that into a whole sensory experience. It’s why podcasts can be so absorbing.
It’s also why they can be exhausting: They keep my brain in a state of heightened concentration. Before I discovered podcasts, I spent most of my alone time listening to music, which would lead my mind to happily wander. With podcasts, on the other hand, I feel like I’m in a constant state of concentration. While there is no specific research into the neurological distinctions between listening to music and listening to stories, from my experience, the latter is much more likely to be all-consuming. When I’m listening to a podcast, I’m focused only on what I’m listening to, rather than using it as a jumping-off point to daydream or ponder new ideas.
Beyond that, Gallant’s research also suggests that my good intentions with my excessive podcast habit may be backfiring; the entire activity becomes less informative if I never give myself any time to let that information sink in. “We need to be able to let the mind wander without consuming content in order to be able to absorb the data, turn it into information, then knowledge, and finally wisdom,” Grabowski explained. “Each stage of that process requires time for evaluation.”
So perhaps my podcast obsession isn’t making me as wise as I feel like it has every time I finish an episode. But the benefits still likely outweigh the potential negatives, said Dr. Steve Schlozman, a practicing psychiatrist and an assistant professor of psychiatry at Harvard Medical School. “Some people do do better with constant background stimuli, while for other people it can be a cognitive hindrance,” Schlozman tells me. “But there’s a very important social benefit, too: When it comes to hugely popular podcasts such as Serial or S-Town, the ‘watercooler effect’ comes into play.” We’re listening to so many of these things at least in part because everyone else we know is listening to so many of these things. And it’s possible that even though I’m not taking the quiet time to process the information alone, by discussing it with other people, or even reading articles and tweets about it, my brain is finding a way to do so, anyway.
And yet Schlozman did encourage me to find a little more balance in my day-to-day life. “The idea of ‘mindfulness’ has become hugely popular, and there is validity to it,” he said. “We can see physiological benefits such as decreased depression and anxiety and increasing immune response, but it can be oversimplified.” We all require time to get our thoughts together, explains Schlozman, but it doesn’t necessarily need to be an hour of intense meditation every day. It’s enough to simply sit quietly for ten minutes enjoying a cup of coffee. Preferably without the audio accompaniment of Michael Barbaro.