Toning up your thinking muscles

In our recent Productive Living newsletter, David Allen talks about “Toning up your thinking muscles.”  Here’s a letter from Frederick Ross, a graduate fellow at The Rockefeller University who shared his perspective on the brain as a muscle.

I’m something between a theoretical physicist, mathematician, and theoretical biologist by profession, so I’ve had to be on very intimate terms with my thinking apparatus for many years.

The conscious, symbol manipulating part of our brain is very much like  a muscle.  It burns massive amounts of energy to use, it’s kind of puny for its purpose (just like human musculature — in comparison, someone once got a chimpanzee to lift a barbell, and kept adding weight…until the chimp got bored at tossed it across the room with no effort when there was 600lbs on it).  It works with constant focus, and it can’t be worked that long.  My experience, and that of many other mathematicians aside from the occasional freak is that four to
five hours a day, five to six days a week, is the sustainable schedule for really heavy mental work.  Not writing, or answering email, but trying to build new mathematics or similar tasks.

But GTD isn’t muscle toning, it’s an exoskeleton.  Like mathematics, the idea is to shove the difficult, energy intensive task of reasoning into an external thing that can be handled without fully powering up the Rube Goldberg contraption of our symbolic manipulation system.  The difference is that I can still go through GTD motions very handily when my brain is already burned out from heavy mathematics.

But there are other parts of our brain which are as important for what I do, but aren’t as much recognized.  They’re kind of amorphous, but the two I rely on most heavily are these:

A part that churns at problems continuously, with no effort and only a sense of background noise when it’s going full tilt.  It goes while I’m sleeping, while I’m eating, while I’m doing heavy thinking on other things.  I put the really sticky things in there and wait for the right connection to make them work to pop out.

A sense of taste, not physically, but in the sense of “good taste” socially.  In this case, it’s “good taste” mathematically or scientifically.  My pleasure/pain response has been reprogrammed over the years to make me notice things that have the characteristics of a fertile area to explore, and make me instantly averse to those which are going to be inherently intractable.  Any practical reasons for studying anything I do are later rationalizations of judgements based purely on taste.

And there are many more funny capacities.  If I tell you a set of logical propositions, you won’t be able to reason about them except by dint of extreme effort.  If I cast them as social relationships, you can effortlessly solve problems that would seem impossible on the face of it.

And only the symbolic reasoning machinery, that unreliable, unstable contraption retrofitted onto our brain at some point in our evolutionary past, yet which essentially let us conquer the world, acts like a muscle.

For another interesting read on the science of GTD, read the study on How GTD Works.

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  1. I enjoyed this insight in particular because it helps me understand my own experience. As a knowledge worker, I think about my relationship to mental work in a similar way to how I imagine an athlete approaches her chosen sport–that is, I’m continually aware of what brings me to my best, when I need rest, and how various “exercises” can improve my mental strength and stamina. As a migraine sufferer, I also think a lot about how to take care of my brain to prevent pain.

    Writing software code means engaging in almost pure symbolic reasoning for an extended time. When I come out of that coding “zone,” I had better have parsed my projects and actions sufficiently well that I can remain productive–for the same reasons that a runner still needs to be able to walk after a sprint–since I’ve still got places to go. Coding is sprinting. No love handles on this visual cortex.

    Interruptions can also be almost physically painful when immersed in code. Having an inbox into which I can “stack” non-critical interruptions (first in, last out) is as important as a computer processor having short-range memory close at hand on the circuit board. Without it, I can actually feel my brain start to overheat, like a CPU.

    Finally, there are times when the scope, variety, intensity, and duration of my daily tasks leaves me mentally tired. I have an @braindead list with useful actions I can take in this state. I don’t have an @just-drank-coffee or @just-ate-sugar, however–but the same principle could apply equally well to the opposite end of the spectrum. Adrenaline and blood sugar spikes are like pouring fuel on the afterburner. But, as we all know, there is a price to pay at the other end.

    Just focusing, consciously, on how to sustain high output with complex, varied, and challenging mental work means treating the muscle of the brain with respect and care. Hearing that others think and operate in this way is a terrific affirmation of some of the instinctual adjustments I make to to tone up my mental game. Perhaps there’s a wide world of “mental athletes” out there who likewise think about the brain, and understand the power of GTD, in this way. I’d certainly love to hear from others who work in this way.

  2. I often experience the use of the part of the brain that works subconsciously at problems when I am working on cryptic crosswords. I will take a look at the clues in the morning and find some of them to be unfathomable… yet when I come back to them later in the day the answers will pop into my head, seemingly from nowhere.
    The brain is a quite amazing organ and my experiences so far with GTD (I’m very much a novice, having only implemented the system very recently) have been incredibly positive in terms of giving my brain breathing space. I feel sure it is just the beginning of what I hope will turn into a creative flood!

  3. Sarah: That is exactly the same part of the brain. It’s wonderful except for two things: I never know when what I put in is going to come out, whether it will be five minutes or five years; and when I’ve put something really big in there, I find that I have trouble concentrating on other things. It really is like being continuously drowned in white noise.

    Robert: There is such a world of “mental athletes.” There’s not much discussion of what to do with the brain because they tend to be pretty smart and often figure it out for themselves, or (unfortunately) burn out. My own work habits were a cycle of obsession and burnout for years, to the point where it was a regular monthly cycle for me. Unfortunately, it catches up with you over time.

    About the best discussion of the care of your brain I’ve ever found is Littlewood’s “The Mathematician’s Art of Work” (you can find it in his Miscellany, or probably somewhere online). It is unlikely to jibe with many employers in the US since it insists on the importance of at least a day and a half a week of complete mental withdrawal from work, and three weeks contiguous vacation a year to let the brain heal.

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