Science of brain "fatigue"

New research suggests that the brain's "executive function," the mental system involved in abstract thinking, planning, and focusing on one thing instead of another, can be fatigued to the point that your ability to make decisions is badly hampered. Scientific American has an interesting survey of studies in this area. The, er, decision whether to read the article or not is up to you. From SciAm:
...What types of actions exhaust executive function and affect subsequent decision-making? Until recently, researchers focused on activities that involved the exertion of self-control or the regulation of attention. For instance, it's long been recognized that strenuous cognitive tasks–such as taking the SAT–can make it harder to focus later on. But recent results suggests that these taxing mental activities may be much broader in scope-and may even involve the very common activity of making choices itself. In a series of experiments and field studies, University of Minnesota psychologist Kathleen Vohs and colleagues repeatedly demonstrate that the mere act of making a selection may deplete executive resources. For example, in one study the researchers found that participants who made more choices in a mall were less likely to persist and do well in solving simple algebra problems. In another task in the same study, students who had to mark preferences about the courses they would take to satisfy their degree requirements were much more likely to procrastinate on preparing for an important test. Instead of studying, these "tired" minds engaged in distracting leisure activities.

Why is making a determination so taxing? Evidence implicates two important components: commitment and tradeoff resolution. The first is predicated on the notion that committing to a given course requires switching from a state of deliberation to one of implementation. In other words, you have to make a transition from thinking about options to actually following through on a decision. This switch, according to Vohs, requires executive resources. In a parallel investigation, Yale University professor Nathan Novemsky and his colleagues suggest that the mere act of resolving tradeoffs may be depleting. For example, in one study, the scientists show that people who had to rate the attractiveness of different options were much less depleted than those who had to actually make choices between the very same options.
Tough Choices: How Making Decisions Tires Your Brain (Scientific American)


  1. this may have something to do with why having someone (or some thing) else make decisions for you is so comforting…although i must admit i opted simply to read the snippet. maybe i’ll read the article later, but i could just stare at this wall over here. it’s a nice little wall.

  2. I imagine this is also why its so much harder to answer the question of ‘what do you want to do with your life?’ when we’re given soooooo many different paths.

    So much easier back in eighteen-aught-two when you’re dad’s a smithy.

  3. This explains why I become a complete idiot in trying to decide what to eat, the bigger the supermarket is.

  4. Wow. Is there such a thing as Brain Atrophy? Because I’m pretty sure I’ve got it. I come from a long line of indecisive individuals. It took me plastic the hamburger ocean at baba ghanoush firefly. What? Where am I?

  5. SLGALT @4

    Totally – that’s why I never shop at Whole Foods. It overwhelms my apparently tired brain.

  6. I am not one to say this ever, maybe I know my own head better than most, but this article makes me say it.
    Thank you captain obvious.

  7. This article confirms one long held belief of mine: cookies are good.

    Now whenever I make a decision, I know to eat cookies as obviously they are an important part of the process.

    If I extend this logic, I should eat cookies all the time (just in case I need to make a decision).

    But why limit myself to cookies? After all, most sweet baked goods are essentially mutated forms of cookies. And what is candy if not a flour-less cookie?

    Thanks to this article, I can finally drop this silly diet. After all, I can’t make decisions without it.

  8. So, maybe now we can all finally understand why all those idiots who disagree with what is obviously the correct choice (my choice) do so; it’s too damn taxing on them to think otherwise.

    Ya’ hear that all youse nut-jobs and radicals!

  9. The Scientific American article uses the word “brain” five times, but (based on the abstracts) none of the peer reviewed research linked employ any kind of neuroimaging. No fMRI, no EEG, no MEG, etc…

    Rather, they all employ behavioral methods and abstract models. Simply stating that (some part of) the brain gets fatigued or depleted buys you exactly nothing in explaining any of the effects discussed.

    Obviously, the brain (and the rest of the central nervous system) are playing a crucial role in the experiments in question, but just as obviously (I would hope), good old behavioral psychology applied to organisms (and, I imagine, groups of organisms) is where the story is.

  10. …the mere act of making a selection may deplete executive resources.

    My work, as a physician, involves making about a thousand small decisions daily, plus a handful that require careful deliberation.

    A few years ago I started saying, around 4PM on typically hectic workdays: “all my neurotransmitters have been used up”.

    (eponymous post?)

  11. So this is why packing boxes in a warehouse after three years of being a graphic designer was, in a strange way, very relaxing.

  12. I’m going to go ahead and draw my own conclusion (argh! using precious choice-fuel to select the correct words):

    As a control freak/perfectionist I make a lot more choices during the day than the average chump. Thus my often crippling procrastination when it comes to doing, you know, important things stems from over-taxation of my mind performing menial tasks that would be better handled by a subservient army of fembots and/or midgets (midget fembots please contact me with a resume and references).

  13. For me, this explains a lot. Back when I was an editor on the Chelsea House Library of Literary Criticism series, a huge amount of my workday consisted of making decisions: researching the available litcrit on an author, selecting material in the stacks, making first-round selections, second-round cuts, final character-counted chapter edit … one judgement call after another, all done at top speed. At the end of the day, I’d find myself reading something like Weekly World News to wind down. I now see why it was so relaxing: reading it involved no judgement. It was all hogwash, start to finish.

    This also explains Martha Schwartz’s dictum that you can only copyedit for so many hours straight before your judgement gets unreliable. Like doing research and editing for Chelsea House, copyediting requires that you make one finicky decision after another after another after another. I used to be able to tell I’d hit my limit when my incidence of queries suddenly ramped up. I wouldn’t feel like I was having trouble making decisions; it was just that there were suddenly more problems in the text that needed querying.

    (Of course, sometimes I’d come back to it later and find that they still needed querying, in which case it was the author who’d run out of vril.)

    Kaiza @13, are you sure you’re not avoiding decisions? If you do a less than perfect job, you have to decide how much is enough. Perfectionism has a single answer to every instance of that question: as much as you can, as well as you can.

    That’s another thing I’m familiar with from copyediting, or rather from being a managing editor who oversaw freelance copyeditors. I knew that when editors asked for “a light copyedit” on a book, one that only addressed certain classes of errors plus only the more egregious cases of other classes of errors, I needed to budget at least as much time as I would for a full copyedit, because the copyeditors would still have to identify all the usual errors, and then on top of that would have to decide which of them were bad enough to need correction and which could be overlooked. It was easier for them to work to their best approximation of perfection.

  14. I am 68yrs old with 2 grown kids. And I have been telling them for 30 odd years how life was so much easier when we had fewer choices to make. You walk into any store now and you are overwhelmed with all the merchandise that you have to sift through to decide what you actually need and want. Now they believe me thanks to your article.
    I also tell them our brain is like a file cabinet and every day of our lives we have new stuff to file. Well, after so many years,, the file cabinet gets so jammed packed that it takes us longer to find that word or piece of info we are looking for. Thats the sometimes effect. Sometimes I remember and sometimes I forget.
    why must progress produce chaos??

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