I ran into a blog post by statistician John Cook, which posits that the ideal amount of concentrated mental effort one ought to do in a day is four hours.

I copied the post, for easy reference if you wish to comment.The original post is also more readable, so please visit it instead. There are links to further evidence of his claim, as well (including accounts of the work habits of many famous authors and scientists): http://www.johndcook.com/blog/2013/02/04...entration/

Quote:As I’ve blogged about before, and mentioned again in my previous post, the great mathematician and physicist Henri Poincaré put in two hours of work in the morning and two in the evening.

Apparently this is a common pattern. Cal Newport mentions this in his interview with Todd Henry.

Now we also know that if you study absolute world class, best virtuoso violin players, none of them put in more than about four or so hours of practice in a day, because that’s the cognitive limit. And this limit actually shows up in a lot of different fields where people do intense training, that you really can’t do about more than four or so hours of this type of really mental strain.

And they often break this into two sessions, of two hours and then two hours. So there’s huge limits here. I think if you’re able to do three, maybe four hours of this sort of deep work in a typical day, you’re hitting basically the mental speed limit, the amount of concentration your brain is actually able to give.

He goes on to say that you may be able to work 15 hours a day processing email and doing other less demanding work, but nobody can sustain more than about four hours of intense concentration per day.

Update: The comments add examples of authors and physicists who had a similar work schedule.

I've found the same: past 4-5 hours of concentrated effort, I get significantly less productive in my work or study (including study of Japanese). This of course doesn't mean that I can't spend 10 hours a day on Japanese, but it does mean that I can't spend more than 4-5 hours being fully focused on a mentally challenging task like learning grammar, reviewing Kanji and sentences, adding new sentences without dilly dallying about, etc. At least half of those ten hours has to be spent doing less intensive work, like reading comic books and watching media. Either that, or I have to slow down the pace of my reviews, to bring down the intensity. However, lately, I learned to avoid doing that (because it's a waste of time, obviously), and instead go full speed for less time.

This is also further evidence that the people who review RtK in 2 weeks or add 100 sentences a day are doing busy-work rather than expanding full mental effort, and will not fully internalize what they studied.

Stansfield123 Wrote:This is also further evidence

If by "evidence" you mean "someone's opinion on the subject", then yes, this is solid gold.

Anyway, for me even two hours of intensive studying is the practical limit. Not because I couldn't go on, but I get something you could call "a language fatigue" where I really need to do something other than study a language or I'll end up quitting my studies altogether, since it doesn't feel that enjoyable activity anymore. I really need variety in my free time...

Granted, this would only happen if I do it a lot, not in a span of one day.

[Zgarbas]

Kinda makes you wonder how those poor college students* manage 12-hours of classes in a row.
*we have this for medicine&science colleges, so it's not like they can sleep their way through them.

Disappointing lack of references. Violinists could limit their practice for other reasons, like avoiding RSI or just because it's how they were trained. It doesn't go to say it's optimal. Surely four or more one-hour sessions would be even more effective. It's hard to say if it hasn't been rigorously tested.

I remember 澤口先生 saying on ホンマでっかTV!? that the concentration limit is around 20-minutes in one go. I'm guessing that would be relatively easy to demonstrate compared to this idea of a daily learning limit. A flat 4-hours sounds too simplistic. Surely you'd have to consider individual factors linked to lifestyle, genetics etc. You're probably still able to learn after any hypothetical limit, but at a diminished rate.

Zgarbas Wrote:Kinda makes you wonder how those poor college students* manage 12-hours of classes in a row.
*we have this for medicine&science colleges, so it's not like they can sleep their way through them.

Not really true that people have 12 hours of classes in a row. If it is, it's idiotic. But, as far as 8 hours goes, it's by not paying attention through most of them, or by paying attention selectively.

Betelgeuzah Wrote:

Stansfield123 Wrote:This is also further evidence

If by "evidence" you mean "someone's opinion on the subject", then yes, this is solid gold.

You missed the part about all the insanely successful scientists and authors who have excelled by practicing this.

[Zgarbas]

Our science&med schools often have at least one 12 hour (8 to 20:00) day, often including practical courses. With med schools it's a bit understandable, seeing how lots of doctors also spend 12+ hours working under stressful conditions so their ability to cope with that is pretty important.
(speaking of which, learning aside, spending time in surgery also requires a lot of concentration and that often lasts more than 4 hours at a time...)

This one time my college accidentally set us up with a 12 hour day as well (we managed to reduce it to 8, but still annoying), but it's not like literature classes require your undivided attention.

edit: And then there's intensive language courses (6-8 hours/day), intensive courses of any kind, schools which usually have at least 6 hours worth of classes per day for 12 years...contests&exams which can be longer than 4 hours... and really it depends on your definition of "concentration".

@Zgarbas: Luckily, there are people like me doing internships.... Just sayin'

But seriously, any surgery requires two docs as far as I know here. One is "only" assisting, though.

[Zgarbas]

I know, I'm just thinking of the various common situations which require more than 4 hours of concentration. Quite a lot =/. Not to mention all the 9-to-5s which actually involve cognitive work&attention (accounting?)...

I think it's important to make a distinction here; these guys usually talk about a kind of very active and deliberate sort of concentration, like practicing a musical instrument for two hours while constantly paying attention to and trying to refine some detail of your technique. I'm not sure if there's some sort of universally agreed-upon definition but I doubt you can equate it with going to class, or even to reviewing kanji.

I agree though that the purported evidence isn't really that great, it's more a collection of anecdotes than anything else.

[Zgarbas]

You can mindlessly practice a song though... I sometimes practice songs I know really well just to see if I remember them, and at one point I just go on auto-mode. Of course, you can't do that with all songs but still. Your fingers just remember what you have to do =).
The fact that if you practice more than a few hours then your fingers will start hurting* and it can lead to various health problems in the long run (depending on the instrument) is a completely different thing =).

*or bleeding. Or you can't use your joints anymore. Or tour hands go numb. Or you get a blister. Or the various diseases linked to instruments ^^...

Just because you can only do 4 hours of extremely difficult work doesn't mean that only the difficult work is necessary.

Outside of his 4 ours of work, I bet Poincare spent the rest of his day thinking about math.

[Zgarbas]

@hyperborea
Yeah, in our case it was just really poor scheduling. basically we had a 12 hour day + 2 days with no classes and 2 days with only one class... Med school though... Med school is crazy. They get almost 40 hours per week...
Also, there's a difference between 2 hours in a normal class and 2 hours in a lab class.

Isn't the fact that this guy is trying to make a general theory based on a "certain kind" of playing, concentration, etc. making the result inaccurate from the get go?

Anyway, I wish I had 4 hours of concentration. Some days I really have to force myself to go through a 30 min study session and end up wasting the day trying to focus, with only 3 hours of study done.

So I suppose 8 hours of school then (on a good day) an hour of homework and finally an hour of Japanese isn't all too effective... I suppose that's assuming I concentrate during (or even do) any of those.

Yeah, I can't really see a bassist being able to play more than four hours without their hands bleeding, even though they initially go over their limit to build up calluses on their fingers.

But yeah, with instruments, a lot of the limitation is physical. Even with proper posture, you still risk things like tendinitis since your posture simply postpones it.

That's not to say I don't think there's a mental limit to concentration. When you concentrate really hard on something, you are running your brain much harder than normal. Doing that without rest would obviously strain that area of the brain after a time. It might even strain the blood vessels that are having to carry more blood than normal for long periods of time.
I guess it's like weight lifting; your intention is to push yourself to a certain point, but after that, you hold back and give room for the healing process to occur. Similarly, you could say that continuing to do things in the language after hitting your limit is good for retention, you just don't concentrate as hard on it. If you don't keep moving your muscles after a workout, they'll seize up, maybe something similar happens to the brain?
(If you couldn't tell by now, I'm just pulling things out my ass. I'm not as versed in human biology as some here.)

Maybe the average but definitely not what I would call the "human limit", there are always exceptions to the rule and a lot of other factors come into play such as upbringing.

I remember hearing the 4-hour limit thing in law school a long time ago, so this is definitely nothing new. Everyone agreed that you couldn't learn more than 4 hours of new material in a day. I think it was in one of those "How to Succeed in Law School!" type books that everybody buys, but won't admit to buying.

Of course, everyone also agreed that chewing peppermint of any kind would improve your brain activity and boost your exam scores.

Stansfield123 Wrote:This is also further evidence that the people who review RtK in 2 weeks or add 100 sentences a day are doing busy-work rather than expanding full mental effort, and will not fully internalize what they studied.

It really must annoy you a lot that some people are doing RTK faster than you.

But yeah, that 4 hours is the limit for everyone when doing normal studying (which includes things like RTK) is complete bullshit. I'm sure you get less effective as time goes on, but that every hour after the fourth one somehow get meaningless is just not true, and I'm talking from personal experience. I spend much more than 4 hours studying or actively working on assignments or projects almost every day and have been doing so for four years soon (university classes, not Japanese) with no problems, except that you often get things done at a slower pace later in the day.

Only spending 3-4 hours a day might optimize your productivity per hour ratio, but when your goal is to finish something as early as possible or when you have tight deadlines this doesn't really matter all that much.

Zgarbas Wrote:Our science&med schools often have at least one 12 hour (8 to 20:00) day, often including practical courses. With med schools it's a bit understandable, seeing how lots of doctors also spend 12+ hours working under stressful conditions so their ability to cope with that is pretty important.
(speaking of which, learning aside, spending time in surgery also requires a lot of concentration and that often lasts more than 4 hours at a time...)

This one time my college accidentally set us up with a 12 hour day as well (we managed to reduce it to 8, but still annoying), but it's not like literature classes require your undivided attention.

edit: And then there's intensive language courses (6-8 hours/day), intensive courses of any kind, schools which usually have at least 6 hours worth of classes per day for 12 years...contests&exams which can be longer than 4 hours... and really it depends on your definition of "concentration".

The fact that the ARE things says nothing about them being effective. Should I look up life expectancy figures to illustrate how effective Romanian medical schools and doctors are?

Zgarbas Wrote:I know, I'm just thinking of the various common situations which require more than 4 hours of concentration. Quite a lot =/. Not to mention all the 9-to-5s which actually involve cognitive work&attention (accounting?)...

The article clearly addressed the difference between doing a regular job and intense concentration. Ironically (re you being a grammar nazi), I'm beginning to wonder about your English comprehension skills.

AlgoRhythmic Wrote:It really must annoy you a lot that some people are doing RTK faster than you.

Right, because expressing my opinion that they're wrong must mean I'm annoyed. There's no way I'm just trying to help newcomers understand the difference between learning RtK and speeding through it in two weeks with nothing to show for it.

Stansfield123 Wrote:

Betelgeuzah Wrote:

Stansfield123 Wrote:This is also further evidence

If by "evidence" you mean "someone's opinion on the subject", then yes, this is solid gold.

You missed the part about all the insanely successful scientists and authors who have excelled by practicing this.

I don't think I did.

You have nothing concrete here. Simply because successful people do this doesn't prove anything.

Stansfield123 Wrote:

AlgoRhythmic Wrote:It really must annoy you a lot that some people are doing RTK faster than you.

Right, because expressing my opinion that they're wrong must mean I'm annoyed. There's no way I'm just trying to help newcomers understand the difference between learning RtK and speeding through it in two weeks with nothing to show for it.

What, your opinion that they are wrong? You are basically saying that they didn't learn anything (which is something you really know nothing about), and that's not really an opinion. If I claim that you don't know a single word of Japanese, is that also my opinion? Recommending newcomers to spend 6 weeks and putting down the efforts of people doing it faster are two completely different things, and you should stick to doing the first. And granted that you have a lot of time on your hands it is very possible to do it faster than six weeks while still keeping a good success rate on your reviews, if you claim the opposite you are wrong.

The central issue here is the words "intense concentration", which may mean different things to different people.

I can spend four hours with my children and feel exhausted, but an observing behavioral psychologist may arrive at a surprisingly low figure of tallied minutes-spent actively interacting. Similarly, I can spend an hour in a lecture, but the take-home-message component might be something like five minutes of material (or even less if the audio quality is poor or if you are simply bored to sobs by the material or delivery :-) ). To put it another way, the city speed limit might be 60km/hr, but an actual trip across town might yield an average speed of 30km/hr, occasionally gusting to the posted limit (or above if you're naughty, inattentive or if your speedo calibration is off).

A lot of what we think of as "work" and "study" is really a waxing and waning of focus and attention (and there are also studies which demonstrate just how much a trivial interruption - phone calls, "checking the spam traps", "just looking something up" can derail focus and consume cognitive time and effort above and beyond that spent on the distraction as the mind re-connects with the main task). You may do a 12-hour or 16-hour day as a doctor, but depending on the circumstances you will almost certainly have a fair bit of routine, almost-no-brainer stuff interspersed with moments of intense focus (disclosure: I might have done six years of med school and twenty years of subsequent practice and I might know whereof I speak, here ...)

This is also why folks with some kind of disability may struggle more with a given task-load, as they may be having to work harder to surmount their own incidental obstacles (further disclosure: I am hearing impaired, which tends to turn normal conversation in my first language into more of a cognitive workout than full fluency should be, and I have to pace my day accordingly. This has not always been the case.)

So I think that the cited time boundary is in respect of a state of maximally active mental effort and efficiency, and I don't think we spend quite as much of our day in that sweet spot as we might think.

ETA: I suspect that this also informs the cliche "work smarter, not harder". That said, I think there are individuals of exceptional native and acquired stamina in all areas of endeavor, and cognition is probably no different. I also think some people access "the zone" more readily and more consistently than do others (and I'm not one of them or I'd have finished the damn book <g>). I would suggest however that most of us kid ourselves at times in respect of just how hard we are pushing the cognitive engine (or are really getting tired out by the other distractions which life piles on as life goes on), and that there is often a pretty big gap between time apparently spent on a task and the actual cumulative engagement with it. Not recognizing this very human reality is one of the barriers to managing your time in a realistic way for YOU.

There might be some limit related to sleep like if you need 1 hour of sleep to consolidate the learning from 4 hours of practice.

I was just thinking that, Corry. Much like sleep itself, which moves through stages and which is most restorative when certain criteria are met?

It may be that some learners more naturally move themselves through the most effective pattern for their learning style than do others. They may have a natural or hard-won sense of optimal pacing.