Nicolas Hulscher, MPH

In 2024, “brain rot” went from an online meme to the Oxford Word of the Year.

Doomscrolling, zombie scrolling, and dopamine-driven streams of low-quality content are producing measurable cognitive impairment across an entire generation.

‘Brain rot’ is defined as “the supposed deterioration of a person’s mental or intellectual state, especially viewed as the result of overconsumption of material (now particularly online content) considered to be trivial or unchallenging.”

Our experts noticed that ‘brain rot’ gained new prominence this year as a term used to capture concerns about the impact of consuming excessive amounts of low-quality online content, especially on social media. The term increased in usage frequency by 230% between 2023 and 2024.

The first recorded use of ‘brain rot’ was found in 1854 in Henry David Thoreau’s book Walden, which reports his experiences of living a simple lifestyle in the natural world. As part of his conclusions, Thoreau criticizes society’s tendency to devalue complex ideas, or those that can be interpreted in multiple ways, in favour of simple ones, and sees this as indicative of a general decline in mental and intellectual effort: “While England endeavours to cure the potato rot, will not any endeavour to cure the brain-rot – which prevails so much more widely and fatally?”

Now, a peer-reviewed paper titled, Demystifying the New Dilemma of Brain Rot in the Digital Era: A Review, confirms that brain rot is real: the digital environment is chemically, cognitively, and psychologically degrading the developing human brain. And the damage is measurable.

According to the study, brain rot isn’t a meme. It’s a documented state of cognitive atrophy, driven by overstimulation, dopamine feedback loops, and nonstop exposure to low-quality digital content.

The authors conducted a rapid review, systematically analyzing 381 studies, filtering to 35 high-quality papers published between 2023–2024. Here’s what they found:

The Core Mechanism: Overstimulation + Dopamine Feedback Loops

The review shows that young people now average 6.5 hours per day online — primarily on algorithm-driven platforms like TikTok, Instagram Reels, YouTube Shorts, and endless-scroll feeds engineered for split-second novelty.

Most of the content involves rapid, low-information stimuli: ultrashort videos, memes, reaction clips, and trivial entertainment fragments that provide novelty without cognitive substance.

These platforms deliver rapid bursts of artificially rewarding stimuli, creating a cycle of:

• Constant cognitive overstimulation

  The brain never enters a “rest” mode or deeper thought state.

• Weakening of working memory

  Information is consumed too quickly to be consolidated.

• Fragmented attention networks

  Short-form content trains the mind to expect constant novelty.

• Difficulty processing long or complex information

  Deep reading and sustained focus become neurologically harder.

• Mental fatigue & reduced executive function

  Chronic overstimulation taxes the prefrontal cortex — the center of planning, reasoning, and self-regulation.

The study describes this as a shift from healthy, top-down cognitive control to bottom-up, dopamine-seeking impulsivity.

Doomscrolling: Chronic Exposure to Negative, Threatening, or Grotesque Content

Many people casually use the term, but the study provides a precise functional definition:

Doomscrolling = the compulsive consumption of emotionally negative or threat-based content.

Doomscrolling produces:

• Persistent anxiety and hypervigilance
  The brain remains locked in a threat-detection mode.
• Rumination loops
  Negative information gets replayed mentally.
• Physiological stress responses
  Chronic cortisol elevation impairs cognition.
• Reduced memory formation
  Stress disrupts hippocampal consolidation.
• Attentional fragmentation
  The brain becomes primed for scanning, not focusing.

According to the review, doomscrolling directly impairs working memory, emotional regulation, and sustained attention, accelerating cognitive wear-and-tear.

Zombie Scrolling: The Dissociative “Mindless Drift” That Damages Cognition

Doomscrolling is emotionally intense. Zombie scrolling is emotionally empty.

Zombie scrolling = passive, intentionless, dissociative swiping through content with no goal, awareness, or engagement.

Zombie scrolling is associated with:

• Dissociation
  The mind drifts, reducing present-moment awareness.
• Working-memory depletion
  Mindless consumption offers no cognitive stimulation.
• Reduced attentional control
  The brain becomes conditioned to effortless, low-value input.
• Emotional numbing & detachment
  Pleasure/reward pathways become desensitized.
• Diminished cognitive engagement
  The brain stops initiating deeper thought patterns.

The review notes that zombie scrolling may be even more insidious because users don’t feel stressed, so they underestimate the damage — yet the cognitive decline accumulates quietly over time.

Preclinical Dementia Signatures Are Appearing in Younger Generations

A striking findings of the review is that digital-era cognitive decline now mirrors several early dementia–like neurobiological patterns. Across neuroimaging and behavioral studies, excessive digital exposure is linked to reduced hippocampal engagement, producing shallow, fragmented memory formation rather than durable consolidation.

At the same time, prefrontal cortex function—which governs planning, inhibition, and decision-making—shows measurable degradation under chronic multitasking and rapid-fire media input.

This constant overstimulation imposes a chronic cognitive load on the neocortex, creating patterns consistent with accelerated cognitive aging. Notably, several longitudinal findings suggest an elevated lifetime risk of cognitive decline, indicating these effects may not be transient. These changes are well-documented through fMRI and controlled studies included in the review, demonstrating that preclinical neurodegenerative signatures are already emerging in younger populations.

Brain Rot: A Real Neurocognitive Syndrome

The study shows a clear, repeatable pattern: excessive digital exposure to low-quality content degrades working memory, sustained attention, executive function, problem-solving, and emotional regulation. Constant notifications and rapid content switching impair information holding and focus, while overstimulation weakens planning, self-control, and cognitive flexibility.

Both doomscrolling’s emotional overload and zombie scrolling’s emotional emptiness destabilize the central nervous system, producing a more rigid, impulsive, and cognitively inefficient brain. Adolescents exhibit the most severe deficits, underscoring the risk of long-term impact.

The evidence confirms brain rot is a real, emerging early, accelerating quickly, and consuming a generation.

This is one of the core reasons why cognitive disability is now a public health concern in the United States. Cognitive impairment is skyrocketing with no end in sight:

New Study Finds Cognitive Impairment Is Skyrocketing Across America Nicolas Hulscher, MPH · Nov 4 Read full story

Widespread cognitive decline before adulthood may soon become the norm as AI-generated “brain rot” content begins to drastically proliferate.

Nicolas Hulscher, MPH

Epidemiologist and Foundation Administrator, McCullough Foundation

Support our mission: mcculloughfnd.org

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Peter Menzies

Better thousands of us die prematurely, apparently, than risk a grownup conversation

About the same time as William Watson’s outstanding book Globalization and the Meaning of Canadian Life was being published in the late 1990s, the newspaper I worked for was sending a journalist to Europe to research a series of articles on how health care systems work in some of those countries.

I mention Bill’s book, which was runner-up for a public policy Donner Prize, because it exquisitely details many of the things Canadians believe about themselves that simply aren’t true. Which was the same reason why the Calgary Herald sent its health reporter (yes, there used to be such a thing), Robert Walker, to Europe – to expose its readers to the fact that there are more than two health care systems: our “defining” one and America’s, both of which are extremes. To the best of my knowledge, that remains the only time a Canadian news organization has taken on that task.

In every country examined in Walker’s reports, as is the case with almost every country in the world, public and private health care and insurance systems maintained a peaceful coexistence and the public’s needs were being met. Almost 30 years later, that remains the case. Also almost 30 years later, neither Bill’s book nor the Herald’s reporting has had the slightest impact on the prevailing media narrative in Canada. It remains determined to perpetuate the fear that any move to increase the role of private health providers or even allow doctors to work in both systems (as was proposed this week by Alberta Premier Danielle Smith) is the first step on the slippery slope to “American-style” health care. This line has been successfully used for decades – often hyperbolically and occasionally hysterically – by public monopoly advocates for Canada’s increasingly expensive and difficult to access systems. We have known for 40 years that once Baby Boomers like your faithful servant turned bald and grey that the system would be unsustainable. But that single, terrifying “American-style” slur has halted reform at every turn.

The Tyee responded with a “Danielle Smith’s secret plan to Destroy Public Health Care” column while the Globe and Mail’s Gary Mason, a Boomer, challenged my thesis here by suggesting it was time for open minds because “the reality is, the health care system in Canada is a mess.”

It is. And at least some of the blame – a lot, in my view – belongs at the door of Canadian news organizations that for decades have failed to fully inform readers by making them aware that there are a great many alternatives to just “ours” and “US-style.”

I was reminded of this in a recent Postmedia story concerning the perils of private health care provision. Referencing a study on MRIs, the story, right on cue, quotes the part of a study that states “It’s a quiet but rapid march toward U.S.-style health care.”

One would not want to suggest that those clinging to that parochial view should be denied a platform. But at the same time, readers have every right to demand that journalists push back and ask advocates for state monopolies simple questions such as “Why do you say that? Could it not be the first step towards UK-, German-, Dutch-, French-, Portugese- or Swedish-style health care?” and open the debate.

But, as it was 30 years ago and likely ever shall be, there is nothing to suggest that approach even crossed the reporter’s mind. Canadians deserve to be fully informed on major public policy matters and the record shows that when it comes to health care, media have largely failed to do so. Stuck in the fetid trench of an us and them narrative that compares two systems at extreme ends of the spectrum, the public is largely unaware that moderate alternatives exist, ensuring that no meaningful reforms will ever take place and tens of thousands of Canadians will continue to die on waiting lists – a story that continues to be of little interest within the mainstream. Better thousands of us die prematurely, apparently, than risk a grownup conversation that could challenge our national mythology and lead us down the path to “European-style” healthcare.

Postmedia’s Brian Lilley has written a defence of the use by journalists of anonymous sources. Lilley’s introduction describes him as coming down on both sides of the issue and that “Using anonymous sources is completely justified, if done right.” Well of course it is, but in my view it’s frequently and increasingly not being done right and its abuse is being exploited by government comms people to control the narrative.

An example of that occurred last week when the Globe and Mail, in a story concerning Prime Minister Mark Carney’s sojourn to the United Arab Emirates, declined to reveal the identity of a source offering very standard information. To wit:

“The (senior government) official, whom The Globe and Mail is not identifying because they were not authorized to speak publicly, said this visit matters because the UAE economy is very much driven by personal relationships – the kind that benefit from face-to-face meetings.”

This story had three bylines – from a senior parliamentary reporter, an institutional investing reporter and an economics reporter. It is inconceivable to me that, between them, they couldn’t find an on the record source who could explain how important it is, culturally, to have face to face meetings, particularly in that part of the world. Doing so would have added some needed thump to a “sources say” story and helped mute criticisms by others in the industry such as John Robson and Holly Doan, the latter stating in a Tweet that “Anon sources are gov’t propagandists.” Others have privately expressed their dismay.

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Meanwhile, I expect Lilley’s piece is worth a read and it’s important to hear all sides but as it is behind a paywall I haven’t got to it myself. It’s also worth pointing out that a recent Reuters Institute survey put Lilley in Canada’s top 10 social media influencers and creators.

Sadly, we have more this week on unnecessary online smartassery by journalists.

First up is Global News’s Sean O’Shea who managed to allow himself to look like a member of Carney’s comms team when he Tweeted his disapproval of some fans’ behaviour at the Grey Cup.

Then came The Hill Times’s Stu Benson, who blasted his alarm from a loudspeaker before deleting.

Honestly, folks, to paraphrase grandpa’s advice and as I have to remind myself from time to time, just because something pops into your head doesn’t mean it has to pop onto your social media feed.

Last week’s column for The Hub on how Diversity, Equity and Inclusion initiatives remain alive and enforced in the nation’s newsrooms is available here. And don’t forget to watch out for the Full Press podcast with myself, Harrison Lowman and Tara Henley on Thursday.

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(Peter Menzies is a commentator and consultant on media, Macdonald-Laurier Institute Senior Fellow, a past publisher of the Calgary Herald, a former vice chair of the CRTC and a National Newspaper Award winner.)