This is a bit of a non-story. The article doesn't go into what measures were taken to eliminate confounding factors, and it seems from the way it's worded that not many were taken. Maybe people who have a more sedentary lifestyle also tend to come from a lower social background, thus are more prone to physical and mental diseases. Or maybe people who sit more tend to be more obese, and it's really obesity that's associated here. It doesn't take a genius to think up more possible confounding variables. Also, a cohort of 35 people is tiny.
My favorite confound is when Pauling convinced many reasonably educated higher SES people that vitamins were a miracle cure-all. Suddenly multivitamins did correlate with higher health outcomes! (Until later studies untangled this and found little broad effect, aside from specific vitamins during pregnancy or specific deficiencies.)
Sort of a pop science self fulfilling prophecy. Or when we do things we think are smart, sometimes we pollute the evidence.
You just summed up Science-daily. Every single day there's a revolution in sciences or understanding if you believe their articles.
Much like your point about obesity, understanding the nature of the sitting seems essential before any worthy conclusions can be made.
However, this studies falls short of demonstrating that "strongly", or the claim than sitting makes some part of your brain thinner.
When looking at the data, age is the most important contributing factor, but the authors do not perform any multivariate measurement of age vs physical activities vs sitting time. Maybe it's because they don't feel the need to since, and they state it:"As with total MTL thickness, physical activity was not associated with any of the subregional thicknesses."
By redoing this study, including a many more participants, across the country, actually measuring physical health parameters instead of simply doing a survey. I also think they should have used non-parametric tests. I don't believe, and they don't show any indication otherwise, that their sampled population had a normal distribution, was in sufficient numbers, and the some of the metrics were independent from each others.
Since their data set is available and rather simple, one can readily redo the tests and find out that the strongest relation is Age vs MTL, that Age vs Physical activities also correlates strongly, as does Age vs Sitting. Contrary to what the authors reported, sitting and activities also correlates... So yeah that's a bust!
There are some obvious avenues to explore -- but it is not clear if anything is going to be available to consumers in the near future.
1. Get management in on the importance of ergonomics in modern work-life. Like needs to be a large portion of budget and discussed with the board important.
2. Culturally teach the importance of ergonomics in computing. Make it a part of prereq college basic IT courses.
3. Interface types will change this equation. VR, wireless-VR, AR, advances in motion capture, and in brain-computer interfaces will offer alternatives that will have to be adapted and evolved into (I'm rooting for a foss future myself, as it will be more agile in the evolutionary process which is ony one of many reasons foss software is superior to proprietary.)
4. Change the outlook on the desk space and it's function. I was in really good shape in the Marine Corps but I still found time to play pc games, which all know can suck hours away, so I designed a workout program for at the desk in my barracks room. I turned what was a sedentary area into an active area just by changing my approach. For example, during CS matches, the rule was every death is max set of dips (using chair arms) squats (by pushing chair back out of the way) pushups, curls, or pullups, etc. Then rotate every time. I've also used balance balls as chairs in order to force me to focus on my core and ab static strength. There are many examples and each person is different, but the desk doesn't have to be a lazy place. (If you are interested in this I would start with horse stances to work with leg strength first and get the bloodflow to the gluteus maximus which is what excessive sitting restricts.)
Ultimately, I've been saying for a while that VR with room sensing seems really promising to me because I envision a future of VR workout sessions, which could be really fun by gamification and get people in shape! It wouldn't be that hard to ship a kettlebell with a motion tracker in it.
I have a game project (planned GPLclient/CC?contentbysub model) with a long goal of getting into that territory, but had to narrow scope away from recently. I'm mostly waiting for VR on gnu/linux to get better, hoping the Vive Pro has made progress in that area.
I love that that's an article, and the ridiculous geekiness it takes to appreciate it. I think we're overdue for someone to write a brief history of chairs, like has been done for salt, longitude, and light sources.
If only someone had invented the cushion.
If it was random sample from general population then I'm betting on watching TV. Studies seem to suggest that if you are doing a lot of cognitive work it is good for your brain and memory. Apart from the somewhat new trend of standing desks, most jobs that are about thinking are done in a sitting position.
It's absolutely atrocious logic since B is in no way implied from A. For instance to show this then you would need to, at the minimum, put the people that all individually do the best at e.g. writing a shopping list, into a group, and then compare them against people that individually do worse but score well on the [again literally] 'Reading the Eyes in the Mind' test that was used to measure 'emotional intelligence'. Of course that was not done, and I don't think it's unreasonable to speculate because we know what the result would be - and that's not publishable. Yet bad science paired with an astounding headline and you are suddenly good to go.
Yeah, a bit of a rant but it's incredibly disappointing how awful the social sciences have become. And that decline pairs ironically with a massive increase in the reporting of their results, which become ever more grand and increasingly clickbaity, in the media.
If the differences are significant, they'll appear with as few as 35 people, carefully selected, and give you a confidence level of X that it applies to a population size of Y.
Whilst I don't know the details of this particular study, I do recall doing homework problems about correlation confidence.
In layman's terms, maybe this example will help:
Imagine a study where they found that 100% of people who were "sitting" had bent knees. Essentially no one could bring their hips and ankles closer together without bending their knees. With such a significant correlation, you could generalize from a population of 10 to one of trillions so long as the ten was randomly chosen, and there were no other correlative factors.
If you take a sample of 35 people in China you can with a reasonable confidence level say all people are Chinese, or perhaps a very small proportion aren't, depends how lucky you get. It's wrong of course, despite Chinese being the majority (17% according to Wikipedia).
It's fine as a preliminary, but it doesn't show anything useful yet other than the need to perform further study IMO.
A report on this should say something like "viability study suggests sitting and brain changes are related but doesn't provide enough confidence as yet". Which it sorta does, from this section on:
>"This study does not prove that too much sitting causes thinner brain structures, but instead that more hours spent sitting are associated with thinner regions, researchers said."
But either ScienceDaily or UCLA have not lead with that information, matching the current style.
How about using a set of long haul truckers? In a before vs after sort of why? Their hours behind the wheel is documented (or should be). I would presume they're sitting behind the wheel :)
Is this going to launch another wave of conflicting articles published every-other-week saying how to minimize it?
"Eat fish 5 times a day while standing!"
"New study: fish 10 times while doing squats!"
"Latest: the fish does nothing! You need a 'weightless desk' in low earth orbit."
Which contradicts yet another article which says that growing new brain cells can improve memory:
So which is it? I think we need scientists to take two contradicting studies and try to find out the root cause of a discrepancy, instead of making a third study. To do that, they need to record as much as they can, and a meta-study needs to look at the actual discrepancies that can account for a change.
Yes, the shorter form being ;-) :
I think we need scientists.
I thought I was having a stroke the first time it happened about six months ago. I realized it was a pinched nerve after looking into it but it took several months to figure out exactly what stretches I needed to do to relieve and prevent them.
I read up on the symptoms and since I didn't feel any "pain" it indicated it was a pinched nerve.
I started doing some stretches lying on my back and sometimes that stopped the "zinging" immediately but not every time. When it did I could feel my spine in the middle of my back "pop". And if I laid flat on my back I could feel my spine had hump in it.
I could also feel some tingling in my feet and legs before it would start zinging me out, so I got to know when they were coming.
One day when I felt the tingling I stood up and raised my arms straight up and arched my back backwards as far as I could and slowly lowered my arms by bringing them down while pulling them behind me as far as I could in a half circle motion. All kinds of "popping" noises happened and the tingling went away instantly.
Over the next few weeks I had just a few full on zingers and when I did that stretch they went away almost instantly. Since then I've made a point to do those stretches several times a day and I've not had a full blown zinger in over a month.
It was bad though. Damn near paralyzing on my left side and I could barely walk when it was happening.
This is just a preliminary study. It´s too soon to get any conclusions. But, it´s a good starting point for a hypothesis. I will like to see the results of the final study, even that is going to take a long time.
I have seen many times links between sedentary life and illness. But this one looks promising as tries to find a mechanism on why this happens at the brain level that may affect cognition.
And yes, before doing a more expensive study, they asked 35 people for a preliminary study. You don´t spend a lot of money to try to prove something without first trying to disprove it on the cheap.
Translation for developers: before spending a lot of time to test something you first do a smoke test. If it passes you invest the time to test it fully. Otherwise, you go back to writing code.
The correlation graphs are awesome!
Not sure you could get a better randomisation if you tried with just 35 points??!
"Sitting correlates to Thinning in certain brain regions"
Can't this brain region become too large? What if the area is enlarged due to inflammation/swelling and these people with "thinning" are those without that problem?
If the brain is too large it is considered a problem:
This guy apparently has the second largest brain ever measured, and he was a serial killer:
There is some optimal size for this region when it comes to certain functions, probably relative to the size of other regions. That size is probably suboptimal when it comes to other functions and there are tradeoffs going on.
The press release seems to be assuming that thinner is bad automatically.
Well, it's not unreasonable.
I don't know of any literature that says that a sedentary lifestyle is healthy for the brain, but a lot of it has found the opposite. I would like to avoid anything that reproduces the neurological effects of being sedentary.
Here are two I found:
>"More sedentary behavior was strongly predictive of more depressive symptomatology and, unexpectedly, of better cognitive performance."
>"Self-reported sedentary behavior was related to better performance on one cognitive task (trails A; p < .05)."
Obviously these are "undesirable" results, so you have to look a little bit deeper to find them.
But you're right on the last point though, about assuming thinner is bad automatically. Heavy and chronic cannabis usage has been linked to an increase in density, but a reduction in total volume, which resulted in a slight overall decrease in IQ. The takeaway from all this being: Cognitive function is affected by a variety of parameters and we got more neuroscience to do still.
I wouldn't put much stock into these type of non-quantitative explanations wherein "this makes that go up which makes this go down", etc.
Usually the researchers measure a bunch of different things, analyze the data in a bunch of different ways, and only publish whatever is "significant". This works at the single lab level and multi-lab level since the "non-significant" results are considered boring and don't get published. By "usually" I mean this is standard behavior. You can call it p-hacking, file drawer effect, and more recently "forking paths":
>"Cognitive function is affected by a variety of parameters and we got more neuroscience to do still."
Sure, that was the case before these studies were done too though.
Sedentary behavior associated with reduced medial temporal lobe thickness in middle-aged and older adults
To calculate thickness, for each gray matter voxel we computed the distance to the closest non-gray matter voxel. In 2D-space, for each voxel, we took the maximum distance value of the corresponding 3D voxels across all layers and multiplied by two. Mean thickness in each subregion was calculated by averaging thickness of all 2D voxels within each region of interest.
It does sound like quite a convoluted process but I don't see where you are getting anything like "density" from that description.
Also, reading the methods closer makes me think these are cherry picked results:
>"Once segmentation is complete, the original images are interpolated by a factor of 7, resulting in a final voxel size of 0.39 × 0.39 × 0.43 mm. Next, up to 18 connected layers of gray matter are grown out from the boundary of white matter, using a region-expansion algorithm to cover all pixels defined as gray matter."
Why 7? Why 18? These magic numbers shouldn't be there without some kind of sensitivity analysis.
Finally, you can see the dimensions of the voxels is something determined by their methods, not a property of the brains.
>"for each gray matter voxel we computed the distance to the closest non-gray matter voxel."
I do admit that whatever they did is difficult to follow without seeing images of the transform etc (and figure 1 does not help), but the idea they are somehow measuring density seems impossible to me.
I thought maybe you had some expertise regarding how they processed the data that could somehow make this (extremely strange thing) happen, but you have not demonstrated it. I guess I do not know for sure what they did without seeing the code, but if that is what they measured it is the most bizarre thing I have heard of when it comes to analyzing MRI data.
Regarding your comment about how incompetent I am, and how extremely strange this MRI analysis is:
Measuring cortical thickness by MRI is a standard technique in neuroanatomy since 15 years ago. And really, a quick search of the literature would have shown you this. But I suppose that's too much to ask.
I simply cannot imagine what you think is going on in order for them to be looking at "clumping" of gray matter as a proxy for density of the tissue via MRI and calling this "thickness".
>"Regarding your comment about how incompetent I am, and how extremely strange this MRI analysis is"
I thought perhaps you knew some technical detail about their analysis pipeline, but you still haven't mentioned anything technical... so I just don't have any idea what you are thinking.
>"Measuring cortical thickness by MRI is a standard technique in neuroanatomy since 15 years ago."
Sure, here is the first article I found regarding "cortical thickness":
"The shortest distance between the pial surface and the white/gray junction is the cortical thickness at each point."
That sounds exactly like what I would expect, nothing to do with density or clumping.
If you maintain your body in a weak state, it would seem that your body would have to maximize its output with a lesser performing system. Imagine trying to perform well when you have a heart that’s got 1/4 the performance of a well maintained one.
Imagine the downstream effects of all this!
The real question should be whether both are also strongly associated with grey hair, number of grandchildren, and taste in film.
The paper was confusing because they reported an average of 7 hours sitting each day and 1500 minutes per week of "physical activity" (3.5 hrs a day). So basically anything besides sitting and sleeping seems to be counted as physical activity.
It does sound like almost anything is counted as physical activity:
"on how many days did you do moderate activities like carrying light loads, washing windows, scrubbing floors and sweeping inside your home"
By now, all sitting studies sound like they're stating the obvious.
Depends on how much you care and how able you are to compel yourself into action.
Almost every one of us reading this is in a position to abbreviate our work with physical activity at the very least. I just wager that most of us are too addicted to comfort to actually do anything about it in the face of the evidence. For example, we already know that a sedentary lifestyle is bad yet most people don't exercise.
In statistics, sample size does not tell you if correlations are significant or not. Which is why it's amusing when someone thinks they are being a statistics pedant by pointing out a small sample size.
An idealized perfect random small sample might be just fine for statistics, but there's little reason to believe that's the sample we're getting. Small samples should be a cause for suspicion.