Zuckerberg says the science isn’t settled. But the harms of short-form video on the brain are starting to showCaty Enders
Recent social media lawsuits have addressed concerns about mental health. But what about its cognitive effects?
A few years ago, when I’d just started graduate work, I was waiting with a grandmother finishing a questionnaire I’d handed her about her 19-year-old granddaughter who was in the testing room next door. They were participating in a study that used brain imaging to look at adolescent development. The older woman had a soft southern accent and a warm laugh.
“What’s funny?” I asked.
“Cellphone use,” she said, gesturing at a question about how much time her granddaughter spent on her device. “When is she not on it? And my younger granddaughter, she just turned 18 – I mean, I think she’d die if you took the phone away from her.”
I told her that’s what I studied – “well,” I said. “Mostly social media.”
“Social media!” She shook her head. “Sometimes I think that’s the worst thing that ever happened to us.”
In the years since, that sense of broad, far-reaching harm has worked its way from our collective consciousness into thousands of high-profile lawsuits currently making their way through US courts. This week, yet another begins in New Mexico, focused on user data and the Cambridge Analytica scandal. In October, teenagers in Los Angeles will argue that Meta, YouTube and Snap caused serious mental health issues.
The most high-profile suits have focused on adolescent mental health, child sexual exploitation and, to a lesser extent, data privacy.
But in the years I’ve been researching how digital media is changing us, I’ve been increasingly concerned with how little we know about its cognitive effects, particularly those of short-form video, the format that now dominates every social media platform.
The vague sense that we are being cognitively hollowed out, dulled and diminished by our latest technology is captured in the term “brain rot”, recognized by the makers of the Oxford English Dictionary as the 2024 word of the year. And the more researchers look at it, the more it seems to describe distinct cognitive changes that are now being borne out by science.
The literature is still limited, but the most recent meta-analysis, published in Psychological Bulletin, examined the roughly 70 quantitative studies focused on the mental health and cognitive effects of short-form video. The majority of this research comes from China, where platforms are heavily regulated. Still the authors found an association with negative cognitive changes – stronger, in fact, than the association with poorer mental health.
The strongest relationships were with attention and impulse control. But relatively few studies looked at anything else, such as memory, decision-making, language or reasoning. In that analysis, the available research on memory amounted to a single study.
Whether individuals described their use as compulsive – or something they couldn’t control – predicted the worst cognitive outcomes.
Mark Zuckerberg and other social media executives have repeatedly argued that current science doesn’t back up public concern. And it’s true that active social media use – connecting with friends and family, sharing updates, writing and creating content – can be psychologically and cognitively beneficial.
The trouble is, tech companies have increasingly ignored the preferences of their users and promoted passive engagement, pushing the zombie-making infinite scroll and time-dissolving short-video feed – a digital format that seems almost universally damaging.
In my own research, I’ve found surprising relationships between memory and both cellphone use and short-form video. These early findings call for replication, but they held even after accounting for depression and anxiety.
The more time young adults spent on their phones, the worse they performed on a test of working memory, the system that holds information in mind while you’re using it. What you rely on to follow an argument or carry out a plan.
And in study participants who described their short-form video use as out of control, episodic memory was measurably weaker. This form of memory might be thought of as the internal record of your own life – the ability to travel back and revisit various moments. It is how we develop our sense of self in relationship to the world over time.
I’ve been dogged by the idea that, due to my own digital media habits, I might be moving through my days with a befogged sense of what I just did. What I should do next.
Even more alarming is the possibility that we are becoming less and less self-aware and creative in our own internal lives. Memory and imagination run on the same circuitry. In a 2007 study, patients with damage to the hippocampus, the brain’s memory hub, struggled to construct imagined scenes. Remembering the past and picturing a reality you haven’t lived appear to be the same act, run in opposite directions. If we are degrading the one, we might be degrading the other, damaging our ability to envision and enact a new future.
Perhaps these cognitive relationships feed on themselves as a sort of cyclone, driving diminished capacity that in turn results in more helpless digital media consumption. Perhaps collective cognitive changes could have large sociological or political implications.
The head of Instagram, Adam Mosseri, said in a state trial in California last February that he doesn’t think Meta products are “clinically addictive”. And on semantics, he’s right. The only behavioral addiction the Diagnostic and Statistical Manual of Mental Disorders currently recognizes is gambling.
But clinical addiction doesn’t have to be the mechanism behind what we observe as problematic use. With all my concerns about the cognitive effects of short-form video, I’ve still been unable to quit Meta platforms. After many rounds of locking myself out, I always come back for the flickers of old Facebook, where I might stay connected to people and communities I care about. Where I can see a friend launch a brilliant new mosaics venture, or my mother organize events for her town’s bike community, thousands of miles away.
A peace negotiator and member of a working group I convened at the Santa Fe Institute described social media platforms as holding our most important relationships hostage. To access them, we wade daily through brain-rotting media we would otherwise choose to avoid.
The price we pay for connection is our own minds.
In its most recent legal settlement, Meta agreed to pay $17bn and make design modifications to better protect 13- to 17-year-olds: a two-hour daily cap across Facebook and Instagram; a lockout between midnight and 6am, with notifications silenced from 10pm; hidden “like” counts; a ban on cosmetic-surgery filters; and the option to return to an un-optimized-for-your-attention news feed.
The settlement doesn’t include rationales or any admissions of culpability. But implicit in the changes is the idea that short-form video, lack of choice, and passive, mindless consumption are the main culprits. Direct messages with personal contacts and long-form content are excluded – the things users both want and that we know are relatively safe.
Though the settlement is only geared towards protecting a subset of adolescents, what research we have suggests social media’s cognitive risks affect teenagers and adults equally. We all have grounds for wanting greater control over our digital environment.
It may be just a matter of time before cognitive research can do for social media what decades of epidemiology did for lead in the 1960s, 70s and 80s: allow concerned citizens to push for corporate changes that make the world safer for everyone.
Science and litigation will continue to lag behind the relentless pace of big tech. Knowing this, perhaps the safest way to approach the digital world, where we now spend most of our time, is to listen to our own minds and bodies. The science is telling us that teens – and their grandmothers – knew intuitively that something was wrong, even if research will take years to prove exactly what it was.
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Caty Enders is a journalist and researcher exploring our relationship to technology. She writes the newsletter Standing in the Current
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