Four Hours of Concentration

I'd be shocked if those 12-16 hours you apparently put in for "weeks on end" are truly your most productive. They may certainly feel "mentally strenuous," but that doesn't mean your cognitive limit isn't decreasing as the days and weeks go on.

I find that I can focus intensely for shorter bursts over a couple hours, but then I hit my limit and need to push the really hard stuff aside for a while. Sure, I can crank through a ton of tedious or menial tasks (and there are certainly plenty of them), but that's really not the same.

When I complain about being expected to sit around for 8, 9, 10 hours a day (and I do occasionally complain), it's not because I'm rationalizing lazy habits or want to get out of work. I love my work.

No -- It's because in only 3-4 of those hours I will finish 90% of what I ultimately get done in a day. The trick is in knowing how to optimize those hours of productivity, and when to go home and give your brain time to decompress.

I'm sure you're working hard on demanding things, but a world-class violinist is probably doing something much, much harder than you are. Even if you don't respect violinists, surely you have to respect that an expert mathematician trying to make a new discovery is working on problems much harder than anyone in the corporate world. So I don't think this article applies to you, or other people working long hours either, or to people who should be working long hours.

I think you define "strenuous" quite weakly. The overwhelming majority of jobs don't require very much cognitive effort, even in software. Most developers hardly ever actually do anything legitimately hard in their day-to-day work.

Proving theorems is a completely different class of work to chipping away at your failed unit tests or knocking together a CRUD app in your favourite language. Maybe a tenth of one percent of software developers routinely do work that is intellectually on a par with mathematical research; The rest are for the most part skilled tradesmen, doing work they understand relatively well.

It is universally accepted that all but the most prodigious musicians do not benefit from more than 4 or 5 hours of practice a day. They can often easily do twelve or sixteen hours a day, but the extra time is simply wasted. Once your reserves of concentration are spent, you're just going through the motions without learning anything. Most conservatories go to great lengths to persuade their students to practice less, because young musicians are often convinced that they can attain mastery through sheer force of effort.

I can sit and transcribe or arrange parts all day long. I can play from sheet music until my hands give out, all the while daydreaming about what I'm having for tea or what chores need doing. I can't usefully improvise or compose for more than about two hours at a time, or more than four hours in a day. I can feel the point at which I start playing familiar riffs rather than truly improvising; When I've run out of ideas and I'm just writing pastiche. There are composers who claim to do regular eight-hour days, but when you look deeper they invariably spend most of that day arranging or transcribing or recording into the computer, stuff that's essentially just admin.

Thanks for being "that guy." I think that your day probably has one or two peaks in it where you do your best work, and the rest is more low energy work (not bad, just not the most effective work on tough stuff.) Also, not all hard workers are created equally, so among those who do hard work, some can do more than others. I agree they become more successful but I do not agree their working habits can always be duplicated.

I certainly agree it is tempting to read about four hours of concentration and use the article to justify four hours of mediocre work.

I believe you were sitting at your desk pressing keys for sixteen hours a day. I also believe you believe you were accomplishing more than you would have at your desk for six hours a day.

It's been shown what actually happens in such a scenario is that your judgment quickly becomes impaired to the point where you are no longer capable of judging how impaired you are; it's the equivalent of being permanently drunk. To be sure, you can still press keys. If the work you're given is far enough below your peak ability, you may even eventually blunder your way into a solution. (Or you may not; last I checked, the failure rate of software projects is still several tens of percent, and stupid hours feature prominently in most of the failures.) But the calendar time to get your job done is longer, not shorter, than it would have been with an intelligent schedule. Degrading yourself like that is nothing to be proud of, and it does nothing but harm to your work as well as yourself.

How many of you are over 25 years old?

I think you may be missing most interesting point of article which is about the cognitive limits of enhancing skill through deliberate practice.

There was an academic paper a few years back "The role of deliberate practice in the acquisition of expert performance" ( a nice summary here - http://blog.vivekhaldar.com/post/3881908748/tldr-summary-the...). The paper breaks down 3 types of activity: work, play and deliberate practice. Work is exercising skills you already know; Play is creativity, fun, exploration; Deliberate practice is building a skill - where expertise is achieved through focused training in a particular skill. The article suggests there is evidence that it takes about 10yrs to acheive expert status in a skill. Malcom Gladwell introduced a similar topic through pop-sci writing "Outliers" - suggesting there was evidence that becoming an expert required 10k hrs of practice.

To me, practice requires the absolute most concentration - unlike 'work', with 'deliberate practice', by definition, you can't supplement skill with experience for efficiency.. to learn you have to evolve skill from more experiences. And I believe thats why the linked articuled a 'cognitive limit' of 4 hours by way of a violinist practicing in spurts of 2x2hrs=4hrs per day.

The last paragraph in the article talks about "four hours of intense concentration per day", and I'm not sure I buy that abstraction because "concentrating" and "training" are 2 different things. The author (and interviewee) is inferring that concentration is the constraint, but I'd suggest its more likely learning/trainability speed constraint.

So, a different interpretation, but I may be agreeing with you own observations. I think deliberate practice shows an upper bound for cognitive limit - but in the sense of new patterns being formed in the brain. I don't think deliberate practice necessarily shows the upper bound for concentration based on the information presented.

What is a typical day for you? You are a founder so I assume your day is broken up into many different roles. This is very different from a programmer or writer who is focused on doing basically one thing for his whole work day. Do you have any health issues?

> Frequently enough I've put in sustained 12-16 hour days for weeks on end to meet a tough deadline

I think many of us have done this here. What I've noticed from doing this is I start to make lots of mistakes that I wouldn't normally. At a certain point, this turns into a vicious cycle where I think slower and make more mistakes so I need to work more to fix them.

Maybe you're superman and can really work all those extra hours at full concentration...but probably not.

Here's an easy way you can check. Use a timer and throughout the day start the timer when you are going into work that requires full concentration and then stop it when you're done or someone interrupts you or you need to go to the bathroom or you break off from your task. Meetings and emails don't count.

I think you'll be surprised at the results.

It might be correct about the 4 hours. It might also be irrelevant for most people. For most disciplines, accomplishing anything consists of some cognitively very demanding work, and a lot of 'admin'. Some violin players and mathematicians may get by on doing only the hard stuff, but most have to apply for grants, participate in conferences, transcribe/arrange, maintain equipment, etc.

For a startup founder I think this is especially true. A lot of the things you do won't be very cognitively demanding. That doesn't mean you can skip it if you want to get anywhere. It doesn't even mean those 'menial' task create less value in your context than the hardcore 100% concentration parts.

Maybe when you've settled down to a predictable working pattern and managed to configure your environment to cater to all the necessary but trivial tasks (and create enough value in your 4 hours to pay for other people taking care of the rest) you can realize this. I'm not there yet.

I have happily programmed for long stretches - refactoring, doing project work, mentoring others. Once you've been a developer a while, you can produce magic without very much mental strain.

Break away from that and do something truly difficult - specification meetings where you're designing a process for huge pieces of hardware that haven't yet been built - studying something complicated and unfamiliar to you - etc - and perhaps you'll find - like me - that you've only got a few hours available to you before your brain turns to mush.

If I were to hire someone, and he claimed he can put in 12-16 hour days for weeks on end, I'd be inclined not to hire, based on the expectation that it means that he's either bullshitting me, or does not understand his own limits.

In 17 years of managing many dozen staff, mostly developers admittedly, in a variety of different settings, I've never seen a someone that managed to be productive with mentally strenuous even a full 8 hour day at a time other than very occasionally when they're on a roll. Generally, the ones that do best are those who manage to spread out their work, take proper breaks and intersperse the rest of their mentally demanding work with "menial" tasks, and who goes home and puts their work away completely.

Maybe your're an exception, but if you are, be prepared that people will either disbelieve you or expect you to prove it. More likely, your idea of "sustained 12-16 hour days" only actually involves a few hours of what the rest of us would consider mentally strenuous work a day.

Put in 12-16 hour days for a while with repetitive, simple tasks taking most of the time when working on something that is overall exciting, sure, that works for a while (though eventually that too tends to produce burnout - I've had to order developers home after the strain starter producing negative results with fewer hours than that).

For me, what works best is that whenever I feel that my concentration is slipping, if I don't feel I have time for a proper break, I will switch to mindless tasks, such as updating my todo list (often spending time breaking bigger tasks into tasks that are realistically small enough for windows of a couple of hours), doing my e-mail, or if I'm home I'll do the housework, and I'll try to "switch off" while I do, practicing mindfulness meditation for the truly "mindless" tasks such as cleaning.

Sometimes I get lucky, and my concentration stays on top for longer in one go, and I cherish those moments, but I "pay" afterwards (e.g. crash on the sofa when I get home, or need to slow down the following day).

Upvoted.

It seemed to me that the research cited was likely a bit thin. I couldn't tune a guitar, so I have no idea about violin players. But there have been notable cases of very hard-working creative types--Flaubert and Sand come to mind, and Herbert Simon (Turing Award, Nobelist in economics) claimed that a 60-hour work week was about right for him.

Anecdotal example: I used to work for a small company where the programmers did both algorithmic design and the implementation. Looking back on that work, I could write code to sling bits from point A to point B all day (and did the 12-16 hour weeks you mentioned for months on end). But there is no way in hell I could do algorithm design for 12+ hours a day for weeks on end. It's extremely dense work. There's no mental breaks while waiting for the linker to run, or long stretches of babysitting the program in the debugger, or breaks of mechanically typing out something you've already thought of. It's just you and a pad of paper, thinking the whole time.

The article refers to mathematical work, which is by its nature very dense, much more dense than other intellectually-demanding jobs like programming. As a programmer, you might spend half an hour now and then thinking through all the potential race conditions in a parallel algorithm. But you don't do it non-stop all day, day in and day out. Most of your time is spent on things that require far less concentration.

You have to be careful not to give too much weight to something that can have self fulfilling prophecy effects- i.e. "I'm going to have a shitty day" sets you up to have a shitty day. I'm not saying its bad to listen to your internal compass, but you have to make sure that you aren't just giving yourself excuses. In my experience, I found that sometimes I have done exactly that, like I have something difficult to do and all of a sudden "my mind is tired, now isn't a good time."

Incidentally, would the 2 hours of concentration take place at home? See: http://dilbert.com/strips/comic/1995-09-15/?CmtOrder=Rating&...

Wow, 2 hours of concentrated work in the morning sounds exceptional to me. With open plan offices -- the norm in Brazil and Japan -- it's damn near impossible to have 20 straight minutes of uninterrupted work: phones ringing, people talking to each other from afar, people interrupting you, etc.

I tend to agree, although I think you can concentrate longer for short, unsustainable durations. My standard schedule in law school was a few hours during the semester, then a few weeks of 8-10 hour days around finals.

My take away from the experience was that 8 hours of real work is really a lot of work. And distractions are absolute poison: internet, cell phone, etc. Nothing quite like locking yourself in a room with just a book and highlighter--no computer, no cell phone, no people. You add those things to the mix and it can easily take a 16 hour day to get 8 hours of real work done.

I don't know about writers and the morning, but there is plenty of evidence that the ideal block of learning or studying is pretty small. For example, you have spaced repetition ( http://www.gwern.net/Spaced%20repetition ), where a few short minutes of studying spread out over time is vastly more efficient than a few big blocks of studying with no subsequent review sessions. And I believe there's a bunch of research on lectures becoming a waste of time after around 15-20 minutes (IIRC, FAA-sponsored).

There are lots of studies that show this actually

http://www.uvm.edu/~pdodds/files/papers/others/everything/er...

Sounds quite similar to the concept of ego depletion : http://en.m.wikipedia.org/wiki/Ego_depletion

I think theoretically less-intense tasks use up your concentration more quickly if you do it intermittently with an intense task. Which I think makes the usual "work 30 minutes, Facebook 5 minutes, repeat" cycle quite devastating to productivity.

I think we overestimate how quickly we can really context switch. It's interesting to look at how people respond to stimulants. People take adderall to "help them focus" but what it really does is magnify what I think is a latent resistance to context switching.

In 'How to Create a Mind', Kurzweil states that Kasparov could simulate 100k board positions in parallel. Which was roughly same working knowledge as, say, Shakespeare with 100k word senses (http://books.google.com/books?id=FCcXiBPurdEC - search for 'board positions' and read next 3 pages).

Further, he suggests that each of the 100k may require 100 pattern recognizers in neo-cortex. That means, the brain needs to configure 10 million patterns in total - these are either newly observed, or new relations formed with existing patterns.

I'm sure its not linear, but if you divide 10M patterns by 10k hours, that means the neocortex needs to add an average of 1 pattern every 3.6s, or 4k patterns per every 4 hours (ie, limit for day). Thats about 400k neurons / day re-purposed for learning through deliberate practice to learn 40 board positions / day in chess.

__________________________

Continuing the conjecture, what we know about about spaced-repetition and mass-repetition might provide some nice bounds for upper limit on how these neurons can be exposed to learning material over 4-hr period to optimize their use as pattern recognizers.

Could make a nice illustrative simulation to speculatively address your question about limits of concentration / learning reservoir.

Your colleagues likely work 4 like you, then bill for 8. Scott Adams (maker of Dilbert) once said this is extremely common in the corporate world, and my experience largely agrees. Much of the other 4 hours may be spent in meetings, lunches, relocating, gossiping, or internet browsing. You're largely paid to be on-site and aware for 40 hours a week, not to necessarily produce anything.

One of Adams' books has a story about someone who took 2 simultaneous jobs at one company. He would show up early on one floor, then take an early lunch and head upstairs to his other job, where they thought he was just arriving late. The employer did eventually catch on, but until then he was paid 16 hours of work for 8 hours of his time.

Coffee.

I've read a couple of Tony Schwartz's books which go into this topic more and helped me to rethink my working habits.

Littlewood was a talented mathematician; pg is an employer of computer programmers. Unless you are doing original research, which, AFAIK, most YC companies aren't, I see no reason why you should limit yourself to 4 hours a day. (Apart from having a life, but that's a separate debate.)

I imagine that any feasible scientific experiment would measure only a crude approximation to reality. How can you randomize someone to a job and a way of working? Most people are not capable of concentrating for four hours a day, or have jobs that don't permit it.

At best you might recruit some undergraduates -- nearly all psychology subjects are college students -- and have them do some artificial task one way or another for a couple weeks. I find anecdotes from successful musicians, scientists, and authors more persuasive than data from an contrived scientific study.

Gladwell is a poor example.

No. But it does mean you can do two tasks in a day if one of them doesn't require a lot of concentration or mental effort, e.g. four hours programming and four hours gardening.

Most of that work isn't that cognitively demanding though. If you're reading research papers or textbooks most of the time the really hard parts have been done for you. You just need to follow along.

Also, with most work there's lots of things that need to do that require relatively little concentration once you've made the cognitive shift.

I think the four hour limit applies to design/creative work or work that requires immense attention to detail.

I'd say most people have little in a day that actively drains this reserve in more than a trickle.

> When I'm really refreshed and interested and doing well and eating right I can pull all nighters and maintain work quality. I can't maintain this for extended stretches at all though.

I pull all-nighters regularly to work on personal projects, and managed to push out 4-6 hours of concentration during them after a full day work, but the key to that for me (with the caveat that I'm close to 38, and probably could push through more when I was in school, but on the other hand I know how to pace myself far better):

- I nap 1-2hour in the evening, after dinner, and then take a 1-2 hour relaxation period where I'll vegetate totally in front of the TV or listening to music punctuated by low-concentration tasks such as making a list of what I hope to achieve (with estimates and times at the night where I hope to get to them, which makes for a hilarious lesson in how bad we are at reliably estimating stuff...)

- I pump myself full of caffeine (usually about 200mg, my caffeine sensitivity is really low) and b-vitamins, and "dripfeed" myself sugar.

- I'll use modafinil to retain alertness when I go off for work the next day.

- I'll go to the gym but focus on cardio, stretches and time in the steam room and make sure I have time to take "the slow train" which gives me a 30 minute nap during my commute.

- I'll make sure to take a proper relaxing lunch break. Sometimes I'll go find a park bench and sit and nap or meditate for half an hour.

- I'll make sure to schedule my daytime work to the times that works best for me, and try hard to get some extra high concentration work out of the way on the "before" days, and do more "menial" tasks on the "after" days to ensure the overall effect on my daytime job is minimal (overall I think I actually end up with a net benefit, as the personal projects I work on generally are learning experiences that are often synergistic to what I do during the day).

- I crash totally the next evening - usually going to bed at 8pm and sleeping until 6am the following day. Everything in my scheduling is geared towards keeping me productive the following day too, but with the expectation that the evening will be totally lost.

- If I at any time see my productivity start slipping at night, I go to bed. If I see my productivity start slipping in my day job, I take a week or two break from this schedule and get to bed extra early, because I know if I don't I'll tend to get into a rut where things take longer and tire me out more, prompting me to get stupid ideas about working even longer. And I never, ever do more than one or two of these a week...

In the end, I'm not gaining any hours per se, but the hours I get are hours where I'm more productive (the alternative for me was taking e.g. 8pm to 11pm on evenings where I'd still be tired and generally wouldn't concentrate well at all). The structure of a nap, slowly easing into it, and then focusing totally while the house is entirely quiet works very well for me. Probably isn't healthy in the long term, though. But I need me time desperately to stay sane (got a 3 year old that otherwise occupies all my time at home when he is awake).

It's a massive hassle just to get that extra block of concentrated time (now, if I could afford to slack off the entire following day at work, it'd be a lot easier :) ), but it feels worth it at the moment. When my son gets older and demands less of my time so I get more time to myself earlier in the evening, I very much doubt I'll keep this up (though I've grown attached to taking 1-3 hour naps in the evening and working a bit into the nap instead, so that I'll probably keep up to some extent)