"Many people also dropped out of the study. Only 96 of the 498 people recruited took part in the last round of testing. The researchers lost touch with 13 people, while 57 people died and 332 declined to take part."
Do studies like this often reach the front page of HN?
I tend to ascribe some value to "It was published in the peer-reviewed British Medical Journal."
Additional thought: Especially because it is essentially supporting the null hypothesis.
Well, one can't criticize the quality of the study without looking how well other studies did. But even if all studies involve a massive drop-out rate, the drop-out rate still seems like something to look at in evaluating the accuracy of the study.
I mean my concern, looking from the outside, isn't relative accuracy, but absolute accuracy. Not "is it as good as other studies?" but "it is good enough that I can rely on it?"
It's called longitudinal analysis or survival analysis, depending on the question being asked.
We statistician got test and models for these.
You can rely on it if the people who are conducting the experiment are competent and know what they're doing.
BTW, it would also be an issue if the subjects were compensated to the point that they differed from the actual population at large.
Fundamentally having more respect for doing things right, the right way, over the /long/ term, including the STEM fields, would be a 'good thing' for any society, but particularly western ones (where often the bad/evil antagonist is based on science or a cold lack of emotions; but the protagonist is based mostly on emotion and feeling instead of logic).
Everyone keeps replying as if my comments imply a demand that "something be done about this". That's not my point. Maybe nothing can be done about it. The situation is still significant or at least appears significant.
You absolutely can.
Scientific studies should be judged on their potential to produce interesting results. This study has too small a sample size to provide results that merit making even the weakest claims about. Even the initial sample size was, frankly, just barely large enough to maybe provide suggestions for future research.
If a meaningful drop-out rate is expected, I would argue that the researchers running these sorts of studies are mostly wasting everyone's time and money for the sake of publishing a few papers.
a rate of drop-out like that would certainly make me doubtful of the results of the study. It seems reasonably likely that people dropped-out in a fashion that would be weighted in one way or another.
Sometimes, you have to trust the quality of the journal and biostatistician if you aren't able to read everything yourself.
I'm reminded of a study using the Nintendo Wii to help keep elderly people mobile. 90+% of them stopped playing immediately, within days, of the researchers leaving.
So you're saying it's logical that a lot of people dropped out? Seems reasonable.
But that doesn't mean that you wouldn't have the problem of the high drop-out rate implying the final people remaining are biased sample. When you are filtering a large number of people down to a small number, making sure that small number is representative of the large number is a hard problem.
Maybe there's no solution or no easy solution. Doesn't change the problem.
If that's the case, then the test should say this in the instructions... (It's a classic example of setting expectations, introducing objections up front..)
> This test may not feel exciting. Some questions could seem childish. Other questions could make people feel silly for marking the incorrect answer. These extremes are required for the study.
Edit: Yes, they did. See ojbyrne's comment.
This is one of the major downsides to longitudinal studies— people are unpredictable.
.. I don't get it, why would you ask that?
(I'm tech lead for this site)
Recently she did a memory test and nearly aced it (28/30). Since then my typically... well, clueless... neighbor has taken an interest in learning how to use stuff like her TV, stereo, talking about better ways to do things around the yard, etc.
Even with my own mother, the true benefit of puzzles is not that its exercising her brain or making her smarter, but its the confidence that goes along with being successful in these things. I think that goes a long way, even though it may be just a step above sugar pills.
For me, I play Simon Tatham's Portable Puzzle Collection (mobile) every day. I have a cycle I go through. If I'm having a bad day, a good win at Galaxies gets me back into the 'you can do this' mindset.
>> Our results suggest that moderate to intense exercise may help older people delay aging of the brain, but more research from randomized clinical trials comparing exercise programs to more sedentary activity is needed to confirm these results.
Are you homo or heterozygous for E4?
the receptors responsible for escorting insulin across the blood-brain barrier can become resistant to insulin, restricting the amount of insulin allowed into the brain. While most brain cells don’t require insulin in order to absorb glucose, they do require insulin in order to process glucose. [..] Despite swimming in a sea of glucose, brain cells in people with insulin resistance literally begin starving to death. [..] Which brain cells go first? The hippocampus is the brain's memory center. Hippocampal cells require so much energy to do their important work that they often need extra boosts of glucose. While insulin is not required to let a normal amount of glucose into the hippocampus, these special glucose surges do require insulin, making the hippocampus particularly sensitive to insulin deficits. This explains why declining memory is one of the earliest signs of Alzheimer’s, despite the fact that Alzheimer’s Disease eventually destroys the whole brain.
researchers have discovered that Alzheimer’s Disease is preceded by DECADES of gradually worsening glucose hypometabolism.
2012 study showed that a low-carbohydrate high-fat diet improved memory in people with “Mild Cognitive Impairment” (Pre-Alzheimer’s Disease) in only six weeks.
https://coconutketones.com/ - Dr Mary Newport's work on coconut oil and low carb diet with her husband with early onset alzheimers and dementia, intended to provide an alternative ketone source of fuel for the brain instead of glucose.
Grain and sugar elimination: that’s huge, because it’s anti-inflammatory. A big driver of cognitive decline and dementia is inflammation. By going grain-free sugar-free we drop inflammation dramatically. If you were to track inflammatory measures like C-reactive protein or interleukin-6 or tumor necrosis factor (TNFα) or other measures, you would see them drop precipitously, as inflammation recedes, and risk for Alzheimer’s with it. - https://www.wheatbellyblog.com/2017/11/preventing-cognitive-...
I wonder how much this has to do with the relative uptake of carbohydrate sources and in particular refined sugars (namely fructose) in the typical diet. It seems the more that we learn, the less good refined vegetable oils and the level of fructose intake in people's diets is. I'm not convinced the amount of refined grains people eat is particularly good either.
However is seems that sugar (fructose specifically) and refined oils (linoleic acid specifically) are particularly bad in the increased quantities since the early 1900's.
I did a google search and found a bunch of resources, but I though some ppl here may have actual experiences to share.
Calories do count, but hormonal response is a primary factor.
Edit: it's worth noting that a certain amount of fat is absolutely needed and is sating in and of itself.
Personally, I don't think the amount of fat you get (in terms of calories) should be lower than the amount of protein you consume, and should come from better sources excluding refined vegetable oils (which are everywhere). My opinion on this is somewhat based on the relative amounts of fat to protein in sources where you get protein naturally. I also feel that not getting enough fat is a big factor in gallbladder dysfunction and stones.
A lot of my opinions are just from common sense, observation and a lot of reading on relatively recent diet and nutrition shifts, and feel levels/extremes can vary based on general health, metabolic syndrome indicators and outright diabetic progression.
Not only is Dual N-Back a great mental workout, but it will also put you to sleep pretty quickly if you set the parameters such that the task is sufficiently taxing. Here's one that should make you tired within 15-20 mins. if you're just starting out:
(1) Set N-Back to 3 (for every category of items that you have to remember, you are trying to remember the repeats in a string that have two items in between)
(2) Set number of item categories to 3 (e.g. Shapes, Sounds, Spatial/Placement, and Colors)
(3) Up the baseline 'randomness' factor or level of pattern obscurity.
I cannot overstate how important (2) is. So many people in the N-Back community care about maxing out (1). IMHO, the real benefits come when you get (2) maxed out while keeping an N-Back of 3. THEN, work your way to up to higher levels of N-Back.
You have a one in a billion short-term memory capacity and don't feel sleepy yet? Okay, throw in some multiple mentalism exercises while literally in the middle of doing the N-Back training. Ex.: visually 'recite' the alphabet backwards in your head with the letters being in mirror image format (so from 'behind').
You'll find it impoasible to get even remotely close to 80% accuracy if you turn the various parameters up high enough, and you'll have an easy way of falling asleep.
People you don't know will tell you things like, "Do crossword puzzles. That will keep you sharp." I'm someone you don't know, and I'm telling you, "If you've decided to do some cognitive training, you should give N-Back training a try in the manner I described."
Maybe it will help you sleep on a night where you have trouble sleeping. Maybe it helps your mental acuity. Maybe nothing. Maybe it will be a waste of 30 minutes for you.
Empiricism is a much more reliable way to know things than hearsay: this is the general reason for the push towards evidence-based medicine. There is every reason to reject unproven therapies, and what you are offering can not be distinguished from fiction. If you want to make a convincing case for this, you have no alternative but empirical evidence.
Personally, if programming, playing an instrument, drawing, learning languages, and studying mathematics, physics, and history aren't enough to keep my mind sharp, I'm probably not going to worry too much about it.
This is an example of hearsay and anecodote:
"Hey Joe, this brand of probiotic worked well for me. You should give it a try."
After hearing that, should Joe then look for meta-analyses of the effectiveness of different probiotic brands, or does he have defeasible justification for trying it out? Maybe you'll say a search for meta-analyses is too stringent, but that you could at least look at anonymous reviews on Amazon. Fine. Then go look at collections of anonymous anecdotal reports in the N-Back community.
You keep trying to describe a form of rigid empiricism, as-if I don't actually know or care about epistemology. I did a concentration in philosophy of science in undergrad, and was an editor/reviewer for an entry on the philosophy of science in the Stanford Encyclopedia of Philosophy. I'm not unfamiliar with empiricism.
(1) Say you're doing a minute long session and trying to catch auditory letter repeats that are supposed to occur around 5-8 times. On more fully featured N-Back progams you can reduce that number, so that only 1-2 repeats (say) occur. This can make it more difficult for some people because they hear too many false positives (if that makes any sense).
(2) You can change up the default parameters so that repeats are more finely staggered. For instance, take the following two strings:
AHJADCBWPORP (repeats are A and P)
AHPACPWBORJD (repeats are A and P)
The default setting for some programs will just create the first type of string, which can make it more predictable, and thus less mentally taxing. You can tune the parameters so that you get more strings like the second.
 PDF: https://pdfs.semanticscholar.org/5237/69252dd1d49cbd473844c0...
Regarding the design, I remember when Google products gave me a similar feeling. Sadly, with "Material Design" usability has sunk to some weird place where I continually ask "where do i click? what CAN i click? stop sliding things around!" in frustration.
Apologies for going off topic (and the mini rant).
The UK has a lot of political problems. But we also have some seriously talented people doing absolutely outstanding work.
It is difficult to really test for this though, because you can't control for people's amount of mental exertion, gaming, learning and puzzle solving over their entire lives, so we substitute things like "knows more than one language fluently," something we can objectively measure and see if there's a correlation. This particular study used a group of people that took the same intelligence test when they were young.
There's been some research that shows some older people's brains have trouble metabolizing glucose and other sugars, and that diets that push ketosis in older people (higher fats, coconut oil, less cereal/crabs) can help some people:
Regardless of this dubious study, I will continue to solve crosswords. Cryptic crossword solvers were prized in Bletchley Park, since it was seen as evidence of lateral thinking.  I used to look down upon quick crosswords since they were too direct, but lately I have tried to time myself solving quick crosswords, and I find that they can be challenging as well when tried in a genuine quick mode - they involve jogging the memory at a very fast rate.
Its not outside the realm of possibility, my hypothesis is that I am very visually dependent when it comes to my sense of balance. Lots of fast-moving visual stimuli without any input to my balance organ probably tunes my brain to not use my eyes as much. There is also something called "Roll adaptation" which is rolling the head under visual stimuli that does not match. Maybe I should roll my head when gaming for even better effect...
In contast to what other news sources publish, this article links the original paper, reviews the metodology, gives some introductory explanations on the subject and provides all sorts of 'further reading' resources.
Really enjoyed it, thanks for sharing!
i did read it
Please edit such swipes or nasty tropes out of your comments here. This is in the site guidelines: https://news.ycombinator.com/newsguidelines.html. We're trying for a bit better than internet median in HN discussions.
Ultimately I'm not entirely sure what the point of science along these lines even is. The big risk is you notice a correlation to something and assume causation. You then start working to try to pursue that end in cases where the correlation is good - or avoid that end in cases where the correlation is bad. And you spend immense energy and resources doing this, only to find that in the end there was no actual causation at all and you just spent immense amounts of time, energy, and resources doing nothing.
Even worse is that sometimes you might pursue the correlation and falsely end up at the desired end thus assuming causality when none exists. Maybe the best example of this is human/animal sacrifice of ancient civilizations. Those sacrifices were not baseless from their perspective. What undoubtedly happened is that at one point a civilization has e.g. a bad harvest. They feel they must have wronged the gods, so they end up sacrificing something. And, completely by coincidence, the next harvest is bountiful. Lo and behold, you now have centuries of human and animal sacrifice in a model where you can ignore any negative outcomes by suggesting it simply means that you didn't sacrifice enough. Keep ramping up the sacrifices and indeed eventually you'll get a good harvest, but it has absolutely nothing to do with the sacrifices you've made.
Or it could just be survival bias. If your mental faculties are in decline, then you would be disinclined to continue competing in chess. I can imagine people would stop competing at that level long before they completely lost their marbles.