Watching TikTok and Instagram deactivates the cognitive control network: Study
rathbiotaclan.com
rathbiotaclan.com
Interpreting fMRI results like this article does is almost always wrong. Different activities produce different patterns of brain activity. You could put someone in an fMRI machine, have them do virtually any activity, and then write a headline saying that doing that activity turns of key brain regions that are important for something. The trick is that all brain regions are important for something. Having them be less active during a task doesn't imply that it's good or bad. It just shows you which parts of the brain are involved in that task.
This blogspam article isn't great. The study at https://www.sciencedirect.com/science/article/pii/S105381192... has more details, like the fact that those brain regions come online while viewing other less-preferred videos. The results aren't really indicative of anything by themself. It would have been more interesting if they compared to something, like watching a long involved movie or playing video games, but they didn't.
Also this post is coming from a fresh account that only spams links to this blog. Maybe the mods will want to switch the link to the actual study instead: https://www.sciencedirect.com/science/article/pii/S105381192...
It is possible that inhibiting certain brain areas for a longer period will change e.g. cognitive skills. There is enough literature on losing skills after inactivity. But this approach can't bridge the gap.
It makes more sense to observer TikTok users' behavior over time. That can give more information about the actual effects, although without nice, colorful blobs.
You can't get any of that from this study.
fMRI results are easy to manipulate into sensational news stories because deactivating a brain region sounds like a bad thing. Those brain regions are not always-on. Their activity declining during a task doesn't mean they start to atrophy or degrade.
The only thing it means is that those brain regions are not as active during that task. Tasks activate different parts of the brain depending on what they require. All of the extrapolations on top of this result are people projecting on to science they don't understand.
This could equally be reported as tiktok puts the mind at ease.
Or tiktok reduces brain activity related to anxiety.
"Related to" is a term that seems to be capable of supporting an unlimited load.
While this podcast episode is not about this particular research, it could have been.
https://www.changetechnically.fyi/2396236/episodes/17378968-...
When I realize I've spent an hour doomscrolling in an algorithmic feed, I don't feel like was 'all there' paying attention that whole period, it sort of washes over you and occasionally it rouses your attention and you pop out of unconsciousness to consume a little nugget of 'content' and then dive back in. It feels not worth it to spend so much time 'away' for a negligible amount of entertainment.
Video games or a book feels way different, like I'm also going under, but I'm going somewhere else, to a place that was crafted by another human with aim of it being worth my time.
I wonder if this mechanism is the same mechanism that impacts, say, swipe-focused dating websites, as well? And Twitter feeds with super-short messages. A lot of the most viral modern tech has been bite-sized content feeds of various types.
It really makes sense now. Emotional dysregulation comes into play and now I wonder that it's not just me who is quietly angry (at Match Group) all the time while still addicted to swipe based dating apps.
> "Matt Mayberry, who works at a California startup called Dopamine Labs, says it's common knowledge in the industry that Instagram exploits this craving by strategically withholding "likes" from certain users. If the photo-sharing app decides you need to use the service more often, it'll show only a fraction of the likes you've received on a given post at first, hoping you'll be disappointed with your haul and check back again in a minute or two."
https://news.ycombinator.com/item?id=28763413 also speaks to this.
(Dopamine Labs is now boundless.ai, only one example, the reward hacking mentioned is everywhere in socials, adult content, sports betting, for reward maxxing)
I look forward to the legally mandated discontinuation of HN. /s
Hysteria typically doesn’t lead to particularly good policy
There were investigations into it after that the conclusions was that nobody believed it or could replicate it: https://nymag.com/intelligencer/2018/01/does-instagram-withh...
Either the person was making something up, or he just didn't understand how hyperscale apps work toward eventual consistency rather than having everything propagated the instant you press the button.
Zuckerberg Knew. A Whistleblower Has the Emails to Prove It. - https://www.gadgetreview.com/zuckerberg-knew-a-whistleblower... - August 19th, 2026
> Armed with engineering documents and internal emails, the states allege Meta built specific features — infinite scroll, autoplay, beauty filters, engagement-optimized recommendation systems — to maximize time-on-platform for young users, while allegedly collecting data from children under 13 without parental consent. A federal judge already rejected Meta’s motion to dismiss, allowing the addictive-design and concealment claims to proceed.
> Frances Haugen’s 2021 disclosures first established that Meta reportedly knew its products could harm young users and chose not to prioritize fixes. Béjar arrives in court with the internal emails and survey data to back that narrative.
US states accuse Meta of covering up research on teen social media addiction in pivotal trial - https://www.theguardian.com/technology/2026/aug/18/meta-chil... - August 18th, 2026
> Lawyers representing 29 US states have accused Meta of covering up internal research showing Instagram was addictive for teenagers. In a packed courtroom Tuesday, on the opening day of a landmark legal challenge, they said the company knew its products harmed children but hid that information from the public.
> The attorneys general disagree, saying Meta “developed and refined a set of psychologically manipulative” features designed to maximize people’s time on its apps. Those include an infinite scrolling recommendation algorithm, constant notification alerts, thumbs-up “likes” and visual filters for altering one’s image.
> “AGs are in the perfect position to get this done,” he added. “We did it with the tobacco settlement in the 1990s. We did it with the companies behind the opioid crisis. We’ll do it again with Meta.”
Meta and YouTube designed addictive products that harmed young people, jury finds - https://www.theguardian.com/media/2026/mar/25/jury-verdict-u... - March 25th, 2026
Sharpe BT, Spooner RA. Dopamine-scrolling: a modern public health challenge requiring urgent attention. Perspect Public Health. 2025 Jul;145(4):190-191. https://doi.org/10.1177/17579139251331914 Epub 2025 Apr 12. PMID: 40219910; PMCID: PMC12322333.
> This manuscript examines the emerging phenomenon of dopamine-scrolling and its implications for public health, particularly regarding mental wellbeing and digital behaviour patterns. While extensive research exists on Internet addiction, problematic social media use, and doom-scrolling, the authors of this paper identify dopamine-scrolling as a distinct behavioural pattern that warrants specific attention from public health professionals and policymakers.
De D, El Jamal M, Aydemir E, Khera A. Social Media Algorithms and Teen Addiction: Neurophysiological Impact and Ethical Considerations. Cureus. 2025 Jan 8;17(1):e77145. https://doi.org/10.7759/cureus.77145 PMID: 39925596; PMCID: PMC11804976.
> Does it matter how many hours we spend scrolling through Instagram? This article examines the neurobiological impact of prolonged social media use, focusing on how it affects the brain's reward, attention, and emotional regulation systems. Frequent engagement with social media platforms alters dopamine pathways, a critical component in reward processing, fostering dependency analogous to substance addiction. Furthermore, changes in brain activity within the prefrontal cortex and amygdala suggest increased emotional sensitivity and compromised decision-making abilities. The role of artificial intelligence (AI) in this process is significant. AI-driven social media algorithms are designed solely to capture our attention for profit without prioritizing ethical concerns, personalizing content, and enhancing user engagement by continuously tailoring feeds to individual preferences. These adaptive algorithms are designed to maximize screen time, thereby deepening the activation of the brain's reward centers. This cycle of optimized content and heightened engagement accelerates the development of addictive behaviors. The interplay between altered brain physiology and AI-driven content optimization creates a feedback loop that promotes social media addiction among teenagers. This raises significant ethical concerns regarding privacy and the promotion of personalized content. This review article offers a comprehensive and in-depth analysis of the neurophysiological impact of social media on adolescents and the moral concerns governing them. It also provides solutions for ethical social media use and preventing addiction among teenagers.
Addictive potential of social media, explained - https://med.stanford.edu/news/insights/2021/10/addictive-pot... - October 29th, 2021
What Makes TikTok so Addictive?: An Analysis of the Mechanisms Underlying the World’s Latest Social Media Craze - https://sites.brown.edu/publichealthjournal/2021/12/13/tikto... - December 13th, 2021
(I have provided subject matter expertise on this topic to federal policymakers, with peer reviewed citations in all cases, I hope I have helped improve your priors to bring them current)
Ask anyone who ever posted on tiktok - "when i first started I got a ton of new followers and likes! "
Coincides with GenZ aging into adulthood after being educated in the debunked "3-cueing" or "whole language" reading education model. So far 40 states have pivoted away from it as states that switched first saw reading comprehension improve.
Whole lot of social experimentation without informed consent being put on people by 50+ year olds who run the world and never had to jump through the same thought policing.
Psychiatrist argues Americans have lost their grit for irrational reality we are forced to live in and actually are snowflakes: https://www.theatlantic.com/podcasts/archive/2024/02/how-we-...
My question here is whether the framing of the content in question “shutting off brain regions” is an honest one compared to what I said above. fMRI is amazing to be sure, but what it tells us is limited.
So without endorsing crap content on any way, I’m very skeptical of this article’s conclusions based on the study in question.
"The researchers caution against reading the deactivation as evidence of impaired cognitive function. As they put it in the paper, “this deactivation should not be interpreted as a failure of cognitive control capacity.” Instead, the team argues the pattern likely reflects an adaptive shift toward low-effort, automatic processing during passive, low-conflict viewing."
my take: if the study authors could qualify a subject's liked videos, they could qualify a subject's liked activities, and study activation thresholds prior to and post short form content exposure. this would provide a better substrate from which to draw such conclusions.
but I don't need a study to tell me that short form content fries the brain ... it fries my brain!
I think screen activity/tiktok keeps us in some kind of purgatory where we can neither fully engage nor fully disengage.
And the regions involved in the default mode network are actually some of the metabolically most active regions in the brain, involved in memory consolidation, future simulation, theory of mind, and self-narrative; among other things.
https://www.biorxiv.org/content/10.1101/2022.08.12.503715v1
It’s task-specific.
Zoning out doesn't change the energy consumption of the brain that much.
https://www.cell.com/trends/cognitive-sciences/abstract/S136...
:)
The mother would not look away from her phone while she sort of tried to answer her.
Truely heartbreaking to watch.
> I'm fine not having the same attention span as people who had to less stuff to do hundreds of years ago.
Maybe, if we're really generous, there's a reasonable version of this argument that you've failed to adequately communicate here... But it really seems like you're trying to say that a short attention span is a good sign of progress, or something?
I know HN and SV in general has a culty addiction to contrarianism, and it rarely elicits more than an eye roll from me. Framing a short attention span as anything other than a bad thing is wild to me, and I honestly don't know how to respond to something like that (or if my sarcasm detector is off). Do we need scientific studies to show that goldfish brain == bad?
After a lifetime of having to prove that my ADHD doesn’t make me a drag on society, call me skeptical of people who insist they know what makes a brain objectively worse than another based on vibes. It’s one thing to discuss the impact of tuning an algorithm to be addictive, it’s another to make a claim that a preference for one form of media over another is a Problem.
Ironically, I’m a pretty heavy reader and find it funny that people treat reading like some paragon of mental discipline when it’s just the media that I find stimulating. I absolutely have a much shorter “attention span” than most people who primarily consume short form video.
Yes, there's always some puritan attitudes involved in how we talk about this. But I do feel that people who can't read a book because of attention issues are missing out on something.
This is a narrow minded view. Just because something works for you doesn't mean it is something we should optimize for.
All great intellects we study today were the polar opposite of this.
The quantity is endless. You can run out of channels, sweep through them a few times, give up, and get bored, while doom scrollers give you an infinite stream of faux-novelty. It's entirely possible to scroll for eternity and never run out of what at least seems, to your limbic system, like information and social stimulation.
The content is generally much lower quality than TV. Even really bad dumb TV is high art compared to a lot of what's on the doom scrollers. It's hyper-optimized for narrow addictiveness and literally nothing else.
There's a closed feedback loop optimization system in place. The site knows you're scrolling. It knows how fast, where you pause, in some cases even where your eyeballs are going. It knows what makes you interact. It knows what you watched before you stopped watching vs what you watched and kept watching. It also has tons of third party data on you and sensor data that often even includes your location. It can optimize its addiction mechanism in a personalized rapid feedback closed loop way that television could never achieve.
It's like a smart drug that tries to keep you hooked. Imagine if the heroin had a learning algorithm that adapted its chemical structure in real time to keep you from quitting and it was powered by fleet-wide learning cross all heroin molecules in the world.
And on the other side, we have glutamate, which is excitatory you can associate this with mania, insomnia, just generally higher energy. These kids were more able to stop the scrolling.
Both these neurotransmitters are going to be controlled a lot by a genetics, but also a lot by diet. GABA and glutamate enter convert into each other through glutamate decarboxylase and it needs vitamin B6, pyridoxine, to do this.
BTW its Social Media as per studies
https://pmc.ncbi.nlm.nih.gov/articles/PMC12329480/
Whole bunch of research,
https://pmc.ncbi.nlm.nih.gov/search/?term=Social+Media
But, my point is its normal Every generation behave differently. We shouldn't judge it even via these studies.
edit: Oh someone changed the title of the post now too.
I found it surprising how little depth the video had
I would like to take this opportunity to state one of my core beliefs: we are all easily programmed meat machines. Accepting this fact is uncomfortable, but important.
We’re living down to it.
Thank you for introducing me to this turn of phrase. I get the feeling that it will become more and more useful in the coming years.
Propaganda artists know this all too well.
(Caveat: I have no expertise with neuroscience or using fMRI machines. I'm mostly basing my comment off pre-replication crisis fMRI experiments that failed to produce useful data upon scrutiny.)
"High-frequency SFV [short form video] use was consistently associated with attentional disruption, reduced executive functioning, and emotional dysregulation."
"Neuroimaging results revealed reduced activation in the Dorsolateral Prefrontal Cortex (DLPFC) and Anterior Cingulate Cortex (ACC) regions ... when participants viewed personalised TikTok videos."
https://www.medrxiv.org/content/10.1101/2025.08.27.25334540v...
"(The ACC) is involved in ... higher-level functions, such as attention allocation, reward anticipation, decision-making, impulse control .. and emotion."
https://en.wikipedia.org/wiki/Anterior_cingulate_cortex
"The DLPFC is ... the highest cortical area that is involved in motor planning, organization and regulation."
https://en.wikipedia.org/wiki/Dorsolateral_prefrontal_cortex
by permitting unlimited short form content and not disallowing child access we are allowing corporations to destroy kids brains. therefore I posit the latest generation has been rendered retarded, which will pose a dire threat to continued stability unless addressed.
The Youtube app now has a "shorts feed limit" under "time management" that will limit your access to the auto-scroll shorts feed to a certain amount per day. Worth checking out!
So i pretty much see, search bar and that text sidebar on my main screen for youtube. Its absurd seeing the standard youtube ui, after using it like this for a couple years now. This also just really really tightens who i follow. If i find myself clicking through to their profile and seeing what they posted and deciding not to watch, i consider that a waste of my time and after a handful of times i might just unfollow entirely.
I have deleted my Tiktok account 5 times. No longer a user.
Write this headline about Mastodon and no one would read it.
I don’t know it seems that regardless of the technology the brain needs dozing off from reality.
Also, books, TV, board games, newspapers didn’t disappear. So it’s compounded in some ways
Reading is obviously healthier than scrolling tiktok.
Why reading mein kampf is healthier than looking at random funny videos?
Both are addictive. The one is more dangerous than the other, demonstrably. Don’t get me started on religious books.
Everyone had freedom to pick their poison so to speak. Now? All tech and screen based.
Hyper-social normalization always falls apart. It's unnatural; modern human biology evolved for thousands solving problems mostly in isolation. Tech fueled distribution of material goods humans need to survive is great as it removed risk to biology. But social normalization sucks.
Whether the socialized motive is appease gods by living up to scripture, keep a job/build career make money, or validate it just normalizes people and if we all know the same shit, why discuss anything with them? We already know the same shit.
To me this is one of the final forms of our current laissez-faire capitalism - we are literally taking away our own agency in the name of "freedom" (of capitalists to maximize returns).
Less brain, no thinking. Me thinks
all more reasons to heavily discourage the usage of short form content , we might require regulations against what is essentially an invisible drug that rapidly replicate and distribute itself among the masses.
Just video?
Does just audio count?
Does a gif count?
What if I make a website that uploads videos at 1/10th the speed, and the user plays it back 10x faster so it becomes short form?
What if i make a video aggregator website that pulls from multiple different sources so the user gets around the time limit per day per user?
What if users just make multiple accounts?
I don't think we are legally equipped to deal with this at all.
if you make a website that provides short form content you are subject. why would an aggregator be excluded?
go ahead and let users make multiple accounts. the current, invalid, answer here is biometric provisioning (done not to protect anything but government and corporate interests). personally I don't care if an adult wants to fry their brain, provided that they have been adequately educated as to the extent of what they are doing to themselves. it's why I included the parental proviso, because protection from brain frying is most important during childhood.