Ego Depletion studies fail to replicate


I’m feeling all vindicated:

A thing I said a year ago in the comments of Slate Star Codex’s post on Baumeister’s book on willpower:

Willpower is kind of an illusion, a manifestation of the conflict between desires at different timescales. Which is why commitment devices, by changing your incentives, route around the problem entirely.

Dweck's Growth Mindset vs Fixed Mindset

Warning: link contains animated gif that makes you want to eat a plate of cookies.


Interesting! I always suspected that “limited supply of willpower” thing might be wrong, or, worse, actually damaging to believe even it it were true. If you believe that using your willpower on one thing will mean you have less willpower for another, then you almost certainly will have less willpower because that’s what you’re expecting from yourself.


Hmm, this is interesting, but I wonder if there are any practical implications for folks? I seem to remember all the pop science advice based on the phenomenon of ego depletion could just as well be based on the idea of limited mental energy in the day.

For example, one implication is tackling more important and more difficult (requiring more willpower and more energy) earlier in the day rather than later. I will continue this practice because even if there is no limited supply of willpower in the sense of two tasks back-to-back, there definitely is a limited amount of mental energy.

Another example: eliminating many small decisions (I seem to remember one prominent example being Obama wearing the same set of suits all the time or something). This practice doesn’t need the idea of ego depletion either… Having to make a thousand little decisions may be less about willpower fatigue in the sense of muscle fatigue, and more about feeling overwhelmed (true “ego” depletion) and stress, leading to feelings of helplessness, pointlessness (lack of motivation/hope), etc.

So my question to all of you. Do you base any of your behaviors on the idea of ego depletion? And will you change any of these in light of this new evidence.

Also, I did find the idea of swishing glucose water for an energy boost interesting, but never bothered trying it. Anyone out there actually try this? Personally, actually consuming calories leads to a slump in energy (food coma) for me, but swishing and spitting may avoid this, so I’d be interested in people’s experiences with this in the real world.


Sure, the practical implication is to not give yourself short-term pick-me-ups (like a cookie to help you concentrate) or to expect yourself to lose willpower when doing something difficult (a belief which would drastically limit your overall motivation).

Hmm, I wonder what evidence you have to say “there is definitely a limited amount of mental energy”? I’m not saying there isn’t, but just wondering what kinds of things that make you experience this. I have a couple competing models I’m thinking about. It seems that attention is the conserved resource in the Obama suit example, and I’m wondering if it’s also the case in the hard-thing-first scenario (the days gets more distracting after the morning with little matters compounding).

Blatantly pasting from the bit in my book I wrote about this:

There are several competing models of willpower. The oldest model says willpower is an innate character trait, and you’re either a strong-willed, disciplined person bound for success, or you’re not. If this model is correct, then you would probably know whether you have a lot of willpower or not much. If you do have a lot, then you can rely on it to carry you through the hard parts on the way to your goals. And if you don’t, then you’d better pick out a smooth path to your goal from the onset, or you’ll fall off.

A more popular model of willpower is that it’s like a muscle. The more willpower you exert, the less you’ll have that day with which to resist further temptations, but the more you’ll have in the future as your will strengthens. Were this ego depletion model true, you’d want to make sure you weren’t going to need to use too much willpower at any given time, leaving your will weak for when you’d need it most. You would avoid Ben Franklin-ing out by trying to do too much at once, and instead aim for a modest exertion of will as you pursued your goals.

A third model of willpower is that willpower works like a muscle only if you believe it does. If you think that resisting a cookie will make you slack off later, then you’re more likely to eat the cookie in hopes of saving willpower for working later, or to slack off if you’ve already done well by resisting the cookie. If you don’t believe in willpower as an exhaustible resource, then the cookie has no effect on slacking off. In this case, you don’t generate the excuses which sap willpower.

Some thinkers have suggested that willpower doesn’t exist, that all of human behavior is explainable without invoking special cognitive intervention to override our natural interests. Psychologist George Ainslie’s response to this is my favorite concept of will: “the will is a recursive process that bets the expected value of your future self-control against each of your successive temptations.” That is, will is simply the process of making personal rules for ourselves that will help us reach our goals, and how much willpower we can muster is precisely how good we are at setting up these personal rules so that the we always prefer to keep our rules than to break them. This is a learnable skill.

The last one–the Ainslie model, based on hyperbolic discounting of different mental processes bargaining about things at different timescales–is what Danny is talking about. Beeminder works well with this model. I like it because it gives you a path to becoming more effective. You just realize that the excuses and exceptions you make, the personal rules you break, are the only thing holding yourself back from trusting yourself to get things done and do what you said you would do, and that trust is basically the strength of your will.


Beside the point of willpower, I always thought it was odd that they faulted the radish-eating/cookie-deprived subjects for coming to the correct conclusion faster (this problem is impossible and not worth my time).


I very much base my behavior on the notion of limited mental energy – I try to minimize how many unnecessary small decisions I have to make when I’m doing draining mental work. I also find the model useful to explain [part of] why poverty is so mentally draining: you care constantly making calculations about what you can and can’t do because money, and how exhausting is that?

But I never really realized that the notion of willpower/“ego” was such core part of the theory. I don’t think my behaviors need to change in light of the new data.


This is sort of an aside but @alys and I were laughing about the “Scientists Should Be Terrified” part of that headline.

Here’s Slate Star Codex’s take on the whole replication crisis thing in psychology:

The heart of it is tearing apart this analogy in a New York Times article about how Psychology Is Not In Crisis:

When physicists discovered that subatomic particles didn’t obey Newton’s laws of motion, they didn’t cry out that Newton’s laws had “failed to replicate.” Instead, they realized that Newton’s laws were valid only in certain contexts, rather than being universal, and thus the science of quantum mechanics was born […]

If that analogy held then physicists would answer like this when you asked what will happen if you let go of an apple:

“Apples sometimes fall down, but equally often they fall up, and we can’t predict which any given apple will do at any given time, and we don’t know why – but our field is not in crisis, because in theory some reason should exist. Maybe.”

You should read the whole thing because everything Scott Alexander writes is delightful. I even read his posts about topics I have (or thought I had) no interest in, just because he’s so fun to read.

PS: Looks like they changed the headline of the Slate piece to “Everything Is Crumbling”. I approve of the cookie pun.


About a year ago, my routine on some days had me drive past a bunch of restaurants close to noon. I was following an intermittent fasting eating pattern, and generally only started eating around 4PM. Some days, even though I wasn’t hungry at all, I would be extremely tempted to pick up something for lunch. (For me, simply being hungry is different from wanting to eat.) Once I got home, though, I knew I could stick to my fast, since I’d be a hassle to go back out.

I have a lot of trouble with distractibility and impulsiveness (thanks, ADHD). It gets worse when I’m not well rested. I have to remind myself to stick to my (insufficiently Beeminded) goals a lot when I’m sleep deprived. This means I should wrap up this post pretty quickly, because it’s 4AM right now.

Before I started being more skeptical about ego depletion, I thought driving past all those restaurants might contribute to getting sidetracked later in the day or the evening, especially on tough days.

Sometimes anxieties would begin to pop up as I was driving past all these restaurants along the lines of, “Oh no, am I depleting my willpower reserves? Crap, crap, crap…” And anxiety is also worse on days where I’m inadequately rested.

I guess I never really questioned ego depletion because it seemed to go along with the idea that parts of you can get tired out. Not recovered = slower reaction time, can’t deadlift as much, less likely to make good decisions. I didn’t believe it because it was analogous, but I was less likely to question it because it fit with a general story.

But now I notice that there have been days where it felt like I experienced a willpower snowball–facing small but difficult things early on seemed to give me the courage to persevere even as things got worse. (This is also just another story, though.)

In the end, I was able to stick to my fast almost every day. Part of the reason was that I could weigh in for my Beeminder goal at a much lower weight if I waited until right before 4PM feeding time. I saved money, lost fat, and got to spend less time eating and cooking. But I thought I might be sacrificing something more than lunch–my remaining willpower for the day. But my worries about ego depletion seem pretty embarrassing now.


This got me looking for what I’ve said publicly about ego depletion. I may never have had the guts to express skepticism of it until Carol Dweck did, around 2011. For example, the earliest thing I’m seeing is this, in 2012:

Here are two Stanford psychologists skeptical of Baumeister’s “ego depletion” theory:
I’m with Dweck and against Baumeister on this.

And most recently I said on Sources & Methods:

There’s a ton of misunderstanding. I’m not sure how much I can say about it but I’m not really a fan of Baumeister’s Ego Depletion model. And I’m not really sure what I think of Dweck’s counterarguments either. I guess I mostly just avoid the psychology literature altogether and I much prefer the behavioral economists and straight up economists. They’re the ones who think of [akrasia] in terms of hyperbolic discounting.

I should probably shut up now before Ego Depletion gets vindicated after all. :slight_smile:

PS: Oh, hey, but as @nick points out above, it was a psychologist, George Ainslie, who came up with hyperbolic discounting. Still, economists (notably Robert Strotz in the 50s and Thomas Schelling in the 70s) laid out the theory before Ainslie came along and proposed a hyperbola as the specific discounting function.

EDIT: I think Strotz and Ainslie really deserve all the credit. Schelling talked about it anecdotally and coined the term “egonomics” but I don’t believe he contributed to the theory.


For me this was the the thematic observation.

This isn’t the first time that an idea in psychology has been challenged—not by a long shot.

This kind of ‘landscape-altering’ problem happens in physics from time-to-time and probably in every science. Every discovery ends up eroding certainty rather than contributing to it.

That leaves us in the dark. Maybe Ego depletion is still a valid concept, maybe it isn’t. More experimentation will be needed to (attempt to) add data to one conclusion or the other.


I didn’t actually know about the ego depletion theory (I guess I haven’t ever read a lot of psychology - it is more or less biological processes in any case, eh?), but hearing about it now, it sounds like total rubbish. And the cookie vs radish experiment - seriously? How couldn’t an influx of sugar affect the results of the puzzle test? (I know that the direct effect of sugar is considered to be psychological, but it still has an effect on our energy levels.)
Maybe indulging in cookies (which they should’n’t have done) caused guilty pleasure effect to strike, and then they didn’t dare also ditch the puzzle. My point being that even if there are measurable stuff like ego/willpower, guiltiness and so on, then how on earth could that particular experiment single out ego, or the depletion of it, as the cause?


I haven’t yet caught up with the latest on this, but I want to draw a distinction between views of willpower that I’ve heard. There have been some simplistic notions of willpower, notably: “Willpower is glucose! If you lack willpower to resist eating sweet things, it’s because you lack blood glucose, and to get that you need to eat the sweet thing.” Yes, I’ve heard that suggested. I see that nutritionist Linda Bacon (the article “Willpower: It’s in Your Head” posted by Daniel) takes a similar line, saying that it’s a myth that someone can use their will to lose weight. Such arguments have always seemed to me to conflict with reality (while containing a large grain of practical truth).

The conclusion that I had drawn from (my second-hand reading of) the research was that our brains try to conserve resources, and have a model of our resource levels. When our brain thinks we’re getting too close to our emergency reserves, we experience tiredness or lack of willpower. Which could explain why swishing a sugar solution in our mouths could give us more “willpower”. Also, believing that willpower is not depleted means that it isn’t depleted… but only for a while, with continued exercise of willpower eventually causing a crash to levels similar to people who were told that willpower was limited. These understandings, right or wrong, come in part from Kelly McGonigal, in The Willpower Instinct (as I remember it).

Obviously that’s not the who story, and it may be bunk anyway, but it makes a lot more sense than “willpower is glucose”. Are we now saying that all the theories about ego depletion and willpower have been called into serious question, or just particular ones?


Now a major motion blog post on the Beeminder blog: Ego Depletion Depletion.


Let me also quote the latest on this from Slate Star Codex:

A new very large study of ego depletion finds the effect does not exist. This is a pretty big deal: since its inception, almost a hundred studies have found evidence of ego depletion, and it’s become an entire subfield of psychology with people investigating all the different factors that make it stronger and weaker. If the whole thing just doesn’t exist and the entire literature about it is a mirage, that’s really damning. A Slate article on the issue very kindly links my review of Baumeister’s book where I raised some of these concerns last year. Neuroscientist and ego depletion expert Michael Inzlicht writes an intense soul-searching essay: “I have spent nearly a decade working on the concept of ego depletion…I’m in a dark place. I feel like the ground is moving from underneath me and I no longer know what is real and what is not”. He adds that he suspects his other research area of stereotype threat may be heading in the same direction, and says that “During my dark moments, I feel like social psychology needs a redo, a fresh start.” Some more discussion on Beeminder forums [that’s here!].


There’s a nice Planet Money episode about Brian Nosek’s experiment where he got a bunch of different labs to replicate experiments published in major psychology journals and found that 60% failed to replicate. They talk about the positive results bias in publication and other factors. Does anyone know if the ego depletion stuff was part of Nosek’s survey? I didn’t read the whole Slate article, but from the scan I did they kind of made it sound like the researchers were specifically trying to debunk ego depletion, but maybe that just makes a better story.


(At the end, this briefly gives reasons to wonder whether the results of the replication report are enough to discredit the idea of ego depletion altogether.)


More anti-ego-depletion news