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Willpower Depletion vs Willpower Distraction

58 Post author: Academian 15 June 2014 06:29PM

I once asked a room full of about 100 neuroscientists whether willpower depletion was a thing, and there was widespread disagreement with the idea. (A propos, this is a great way to quickly gauge consensus in a field.) Basically, for a while some researchers believed that willpower depletion "is" glucose depletion in the prefrontal cortex, but some more recent experiments have failed to replicate this, e.g. by finding that the mere taste of sugar is enough to "replenish" willpower faster than the time it takes blood to move from the mouth to the brain:

Carbohydrate mouth-rinses activate dopaminergic pathways in the striatum–a region of the brain associated with responses to reward (Kringelbach, 2004)–whereas artificially-sweetened non-carbohydrate mouth-rinses do not (Chambers et al., 2009). Thus, the sensing of carbohydrates in the mouth appears to signal the possibility of reward (i.e., the future availability of additional energy), which could motivate rather than fuel physical effort.

-- Molden, D. C. et al, The Motivational versus Metabolic Effects of Carbohydrates on Self-Control. Psychological Science.

Stanford's Carol Dweck and Greg Walden even found that hinting to people that using willpower is energizing might actually make them less depletable:

When we had people read statements that reminded them of the power of willpower like, “Sometimes, working on a strenuous mental task can make you feel energized for further challenging activities,” they kept on working and performing well with no sign of depletion. They made half as many mistakes on a difficult cognitive task as people who read statements about limited willpower. In another study, they scored 15 percent better on I.Q. problems.

-- Dweck and Walden, Willpower: It’s in Your Head? New York Times.

While these are all interesting empirical findings, there’s a very similar phenomenon that’s much less debated and which could explain many of these observations, but I think gets too little popular attention in these discussions:

Willpower is distractible.

Indeed, willpower and working memory are both strongly mediated by the dorsolateral prefontal cortex, so “distraction” could just be the two functions funging against one another. To use the terms of Stanovich popularized by Kahneman in Thinking: Fast and Slow, "System 2" can only override so many "System 1" defaults at any given moment.

So what’s going on when people say "willpower depletion"? I’m not sure, but even if willpower depletion is not a thing, the following distracting phenomena clearly are:

  • Thirst
  • Hunger
  • Sleepiness
  • Physical fatigue (like from running)
  • Physical discomfort (like from sitting)
  • That specific-other-thing you want to do
  • Anxiety about willpower depletion
  • Indignation at being asked for too much by bosses, partners, or experimenters...

... and "willpower depletion" might be nothing more than mental distraction by one of these processes. Perhaps it really is better to think of willpower as power (a rate) than energy (a resource).

If that’s true, then figuring out what processes might be distracting us might be much more useful than saying “I’m out of willpower” and giving up. Maybe try having a sip of water or a bit of food if your diet permits it. Maybe try reading lying down to see if you get nap-ish. Maybe set a timer to remind you to call that friend you keep thinking about.

The last two bullets,

  • Anxiety about willpower depletion
  • Indignation at being asked for too much by bosses, partners, or experimenters...

are also enough to explain why being told willpower depletion isn’t a thing might reduce the effects typically attributed to it: we might simply be less distracted by anxiety or indignation about doing “too much” willpower-intensive work in a short period of time.

Of course, any speculation about how human minds work in general is prone to the "typical mind fallacy". Maybe my willpower is depletable and yours isn’t. But then that wouldn’t explain why you can cause people to exhibit less willpower depletion by suggesting otherwise. But then again, most published research findings are false. But then again the research on the DLPFC and working memory seems relatively old and well established, and distraction is clearly a thing...

All in all, more of my chips are falling on the hypothesis that willpower “depletion” is often just willpower distraction, and that finding and addressing those distractions is probably a better a strategy than avoiding activities altogether in order to "conserve willpower".

Comments (19)

Comment author: free_rip 01 June 2014 10:30:45PM 16 points [-]

An even more recent study has failed to replicate the glucose effect entirely, too: Lange, F., & Eggert, F. (2014). Sweet delusion. Glucose drinks fail to counteract ego depletion. Appetite, 75, 54-63 <-- This one also has an interesting survey of the methodological flaws in similar studies.

Also, there's some evidence (still preliminary) that ego depletion effects decline with age: http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0026351 <-- free access paper if anyone wants to read it. It basically looks at a meta-analysis by Hagger done about 2010? I think, and shows a significantly higher effect for younger people (which, being psyc and reliant on college students most of the time, is most of them) - then conducted their own study and found the same (using groups of <25 vs. 40-65). Since 25 is approximately when the pre-frontal cortex is fully finished maturing, maybe the effect has something to do with that.

Also, in terms of the 'out of willpower' and giving up thing... several studies have shown that with sufficient incentive (money, being told the research will help develop Alzheimer's therapies) the ego depletion effect goes away (but then comes back triple-fold on a third non-motivated task). Also, people tend to conserve willpower when they expect to need it later. So you don't have to give up, it might just be a bit harder - but if a few dollars (literally what it was) can motivate someone out of it then you can probably motivate yourself out of it for anything important. This is where the muscle analogy comes into play, like an athlete resting for a big match then pushing through discomfort during it.

^Ref for the last paragraph: Muraven, M., Slessareva, E. (2003). Mechanisms of Self-Control Failure: Motivation and Limited Resources. Personality and Social Psychology Bulletin, 29(7), 894-906

All in all, I'm not convinced one of those things is going on, because there's no explanation there as to why they would happen more for a task that requires self-control than one that doesn't. Most ego-depletion studies match up tasks to make them the same domain, often the same length and tediousness. Why would a task requiring more self-control give you more physical discomfort, hunger, thirst or indignation? The anxiety about willpower depletion I can get behind, but that's only for people who know what they're being tested on.

Comment author: AeroRails 02 July 2014 08:16:54PM 0 points [-]

There was also a 2011 article by Kurzban that argues against glucose depletion being the cause behind the "Ego depletion" effects seen in Baumeister's studies.

Comment author: Kaj_Sotala 02 June 2014 02:43:45AM *  9 points [-]

Related earlier posts: Kurzban et al. on opportunity cost models of mental fatigue and resource-based models of willpower, Deregulating Distraction, Moving Towards the Goal, and Level Hopping , Why Self-Control Seems (but may not be) Limited, also this comment.

From the paper discussed in the first one:

Take, for example, the reaction to our claim that the glucose version of the resource argument is false (Kurzban 2010a ). Inzlicht & Schmeichel, scholars who have published widely in the willpower-as-resource literature, more or less casually bury the model with the remark in their commentary that the “mounting evidence points to the conclusion that blood glucose is not the proximate mechanism of depletion.” ( Malecek & Poldrack express a similar view.) Not a single voice has been raised to defend the glucose model, and, given the evidence that we advanced to support our view that this model is unlikely to be correct, we hope that researchers will take the fact that none of the impressive array of scholars submitting comments defended the view to be a good indication that perhaps the model is, in fact, indefensible. Even if the opportunity cost account of effort turns out not to be correct, we are pleased that the evidence from the commentaries – or the absence of evidence – will stand as an indication to audiences that it might be time to move to more profitable explanations of subjective effort.

While the silence on the glucose model is perhaps most obvious, we are similarly surprised by the remarkably light defense of the resource view more generally. As Kool & Botvinick put it, quite correctly in our perception: “Research on the dynamics of cognitive effort have been dominated, over recent decades, by accounts centering on the notion of a limited and depletable ‘resource’” (italics ours). It would seem to be quite surprising, then, that in the context of our critique of the dominant view, arguably the strongest pertinent remarks come from Carter & McCullough, who imply that the strength of the key phenomenon that underlies the resource model – two-task “ego-depletion” studies – might be considerably less than previously thought or perhaps even nonexistent. Despite the confidence voiced by Inzlicht & Schmeichel about the two-task findings, the strongest voices surrounding the model, then, are raised against it, rather than for it. (See also Monterosso & Luo , who are similarly skeptical of the resource account.)

Indeed, what defenses there are of the resource account are not nearly as adamant as we had expected. Hagger wonders if there is “still room for a ‘resource’ account,” given the evidence that cuts against it, conceding that “[t]he ego-depletion literature is problematic.” Further, he relies largely on the argument that the opportunity cost model we offer might be incomplete, thus “leaving room” for other ideas.

Comment author: ChristianKl 16 June 2014 09:11:29AM 8 points [-]

I once asked a room full of about 100 neuroscientists whether willpower depletion was a thing, and there was widespread disagreement with the idea.

In which year did you do the asking?

Comment author: Academian 29 June 2014 04:58:36PM 4 points [-]

Great question! It was in the winter of 2013, about a year and a half ago.

Comment author: jimrandomh 03 June 2014 04:51:38AM 6 points [-]

Indeed, willpower and working memory are both strongly mediated by the dorsolateral prefontal cortex, so “distraction” could just be the two functions funging against one another.

If true, this is the most important thing I have read in several months. Thank you.

Comment author: Viliam_Bur 17 June 2014 11:06:56AM 4 points [-]

How specifically to use this? When you face a situation that requires a lot of willpower, you should try to clear your working memory somehow. Meditate. Make written notes. Not just generally, but right before you do the task that requires the willpower.

I am not sure if I am not falling prey to confirmation bias here, but when I think about situations where I had emotional problems to do something at work (like: I know what I should do, but I just feel a huge distaste I cannot overcome, so I am unable to focus on the task), it usually was a situation where I was required to hold too many pieces of information in my memory (e.g. undocumented code plus dozen verbally given requirements plus random distractions). Taking a piece of paper and writing everything down helped a lot. It was not just intellectually easier, but also somehow emotionally more okay. This doesn't happen when I write my own code, probably because I code in a style that doesn't require remembering many things. -- I am still confused that people around me don't seem to have this effect, but it could be because I store things in my memory differently, so I deplete my working memory a bit faster. (This doesn't necessarily mean my memory works worse, just that it works untypically, so when people around me optimize things for how their memory works, the result doesn't work as well for me.)

Comment author: coyotespike 22 June 2014 05:46:06PM 4 points [-]

This article has materially helped me over the past couple of weeks. Before, I believed that ego depletion occurred from physical, mental, or emotional effort, and I viewed it as a depletable resource. This gave me a massive excuse to slag off after I finished a task.

But the idea that willpower gets a boost as soon as the brain perceives a reward gave me a different way to look at it. Now, I focus on the reward/'hit' I get from achieving small goals. As long as I celebrate each finished task, I win, and my willpower should increase rather than decrease!

This makes me feel like a badass. If I can keep the big picture in mind, and see how each small goal advances me toward my ultimate goal, and only get more revved up everytime I finish a task, then I'm a freaking Punisher.

So thanks.

Comment author: Qiaochu_Yuan 16 June 2014 04:23:23AM 4 points [-]

Thanks for writing a post about this!

Comment author: buybuydandavis 16 June 2014 03:01:49AM 3 points [-]

A thought on akrasia:

I wonder how much "going meta" is a serious hindrance. Attentional and decision resources are then spent at the meta level instead of the base level. Too much in the moment confusion, optimization and consideration of process, and not enough doing.

Comment author: Viliam_Bur 17 June 2014 11:11:17AM *  0 points [-]

One probably shouldn't try to work on the meta level and on the base level at the same time. Go to the meta level, make decisions, write them down, plan your following tasks, schedule your next meta-level time. Then go back to the base level, and follow the plan, until you are finished or something unexpected happens. (Maybe even drink some alcohol while on the base level, to reduce your going-meta abilities. I am not completely serious about this, but a few times it really helped.)

Comment author: buybuydandavis 18 June 2014 01:12:05AM 0 points [-]

That's about my theory as well, even down to the booze to turn off the inner Critic.

However, in any problem solving enterprise, "something unexpected happens", and the wheels start spinning.

Comment author: buybuydandavis 16 June 2014 02:53:38AM *  1 point [-]

willpower depletion" might be nothing more than mental distraction by one of these processes

I view it as competion by different processes for a shared resource.

A robust system would have built in mechanisms for time sharing, so that one want doesn't always override the others. Different wants get allocated only so much, and then has to compete again, but at a handicap; some handicap associated with the want, some handicap associated with the justification/payoff for the want.

I'd guess that cycling different stimuli would be more effective than using the same one again and again, and that timing the reinforcement well prior to a "give up" might be effective as well. Keep "topping up" the motivation, instead of letting it run down entirely.

Comment author: gworley 15 June 2014 09:43:50PM 0 points [-]

I suspect boredom to be another thing that can result in willpower depletion: it's hard to stay engaged in something when it's boring. It may be possible on less difficult tasks to keep going longer, but it eventually begins to drain on you (although maybe this is covered by wanting to do some other specific thing, but I suspect it was distinct in that you can be bored without having something you would rather be doing).

Comment author: NancyLebovitz 03 June 2014 11:53:57AM 0 points [-]

Maybe try having a sip of water or a bit of food if your diet permits it.

Why not have enough water so that you aren't thirsty?

Comment author: linkhyrule5 03 June 2014 10:52:36PM 1 point [-]

If that's the problem, sure. These are just simple diagnostics. Similarly, if you lie down to read and you feel nap-ish, go actually take a nap.

Comment author: geniuslevel20 06 June 2014 04:16:09AM 0 points [-]

While these are all interesting empirical findings, there’s a very similar phenomenon that’s much less debated and which could explain many of these observations, but I think gets too little popular attention in these discussions.

But you don't explain the findings!

I once asked a room full of about 100 neuroscientists whether willpower depletion was a thing,

I don't even know what that question is supposed to mean.

Comment author: ChristianKl 16 June 2014 09:12:22AM 1 point [-]

I don't even know what that question is supposed to mean.

Understanding questions isn't always trival. If you want to understand the question in depth reading Rob Baumeister's book Willpower will give you the background.