Observational study with an MRI at the end and user-reported activity histories. The results indicate a correlation, not necessarily causation. The study authors don't pretend to imply causation and are straight with these facts.
You can't randomize humans to either do a lot of TV watching for years or stay away from TV for years. So you can you safely assume any study making these correlations is not randomized. It does not mean it should be discarded.
There are a lot of other studies looking at how cortical volume can be preserved through aging with other interventions, however. There are a lot of before/after studies showing aerobic exercise can reduce the brain volume loss associated with aging - https://pubmed.ncbi.nlm.nih.gov/41491407/
So despite this being a correlation study, the result is not surprising. Sedentary activity is correlated with slightly faster degradation of multiple brain measures.
What is interesting in this study is that sedentary work that was intellectually challenging appeared to be somewhat protective. This is also consistent with past studies with before/after measurements around interventions like really intensive skill learning or even meditation.
Just to drive that home, "Study participants also did not undergo a baseline MRI", which of course could mean that they already had some of these brain changes, which may have driven more TV watching.
>Sedentary activity is correlated with slightly faster degradation of multiple brain measures.
It seems to matter what you do while you're being sedentary, at least according to this study. From the article: "Strikingly, the sedentary element of TV watching didn’t appear to be the main driver for these changes."
Maybe the same could be said about the Marvel films. You don't have to concentrate much, but you are guessing some of what is going on.
Some programmes do require some more imagination or interaction. A murder mystery, if it's any good will get you wondering whodunnit. If you are watching a better quality gameshow, you may be at least attempting to answer the questions. Or both may be wall paper.
>Those who reported high amounts of sitting at work actually had larger frontal and occipital lobes, as well as reduced white matter hyperintensity volumes, indicating better brain health than among those who sit to watch TV. This could be due to the intellectually stimulating nature of many sit-down jobs, say the study authors.
Most curious part of in this article is the active vs passive sitting distinction. Occupational sitting (or performing intellectual activity while sitting) correlated with better brain scans and white matter.
This makes sense, if I view it as consumption vs processing thing.
TV is pure consumption, Intellectual work requires output and creation.
If this thesis holds, the rise of AI tools is a bit concerning for knowledge workers. We are shifting from active creation (writing code, writing articles, designing, etc) to passive consumption and curation (reviewing AI generated content).
Will be interested to learn more on how this study unfolds further.
I have friends who self admittedly don't "watch TV" but they watch every single hyped up Netflix series available.
Are they watching TV? By this study they probably not. Are they watching TV? I'd say most likely yes, they also use the device called TV to watch Netflix
I haven’t had home television service for nearly 20 years, but I watch my TV constantly. It’s the same thing with a different delivery mechanism.
Also, is one watching "The Real Housewives of <place name>" on Bravo or an author interview on CSPAN.
Science doesn't work by looking at things and saying what's "obvious" or "common sense", because what's supposedly obvious or common sense is often actually false.
There's more variety of content on youtube, whereas I think TV sometimes caters to lowest common denominator (although that's less the case in the era of streaming: TV is much higher quality than it was when this study started in 1987).
On youtube, you could watch lots of silly dancing videos, car crashes, etc., possibly rotting your brain. Or you could watch history lectures, book reviews, documentaries, etc.
If it notices you are interested in something, it will show you a glut of content on that particularly subject. Some of the videos are just churning out similar content. If you click on a Monty Python video, Python takes over your suggestions. Nothing against Python, I just want to watch a variety of things.
Reading and stage plays require heavier use of the brain too. In the case of reading, you both interpret the words and in many cases visualise things based on them.
Perhaps people who already have small brains watch more TV. Or perhaps exercise is important to brain size, and people who can’t exercise watch more TV. Or maybe not watching TV, and doing other things with your time, grows your brain size.
By this, I mean I never turned on the TV to see what's on the television. I used the TV as a monitor to play games or watch movies from streaming services at times.
Given that I moved to the UK after I stopped watching TV, I barely know which channels even exist on the TV.
I do watch a lot of stuff on YouTube. But it's things I chose to watch because I find them interesting, and I don't find most of the stuff on TV interesting enough.
And the interesting parts, usually, you can find them on streaming services and only watch those whenever you want to watch them. Even scrolling brain rot on Instagram seems less of a waste of time. At least the algorithm knows the type of brain rot I like.
I wonder how many people still watch TV today.
Intuitively both seem plausible. More research needed!
edit: thats great... addressed in the first paragraph.
There was some exclusion of other factors in the study per TFA.
<https://en.wikipedia.org/wiki/Communications_in_Saint_Helena...>
Total population (2021): 4,439. <https://en.wikipedia.org/wiki/Saint_Helena>
Additional areas: South Africa and Tanzania saw television introduced relatively recently, 1975 and 1994 respectively. Those would be larger populations, though confounded by other factors (poverty, racism, higher early-adult mortality due to HIV/AIDS).
<https://en.wikipedia.org/wiki/Geographical_usage_of_televisi...>
That could be interesting.
Mid 1990s is earlier than I thought. Places like Tristan da Cunha and Pitcairn Island may be even later.
throwaway27727•18h ago
dozerly•18h ago
tptacek•18h ago
dredmorbius•18h ago
The other mechanism is.
Even were the relationship not causal, it is at the very least likely exploitable.
tptacek•17h ago
dredmorbius•17h ago
Though a fair effort.
andor•6h ago
The case of watching a lot of TV is a bit different though because it's about attention. Time is limited and it makes a difference whether I do something intellectually stimulating or not. If I spend 8 hours per day creating things, writing software, learning languages, etc., that is going to develop my brain in a different way than 8 hours of watching TV does.
Now to the point about the bad look: even if the study could not prove a causal relationship, why would you even risk it? There is little to gain from watching lots of TV and you'll end up healthier and happier by prioritizing other things.
jldugger•18h ago