This brief essay was stimulated by a chapter by Baumeister (2019), which can be accessed at https://psyarxiv.com/uf3cn/.
“Fatigue,” though a common word, is far from being a boring or neglected concept. A quick search on PsychInfo reveals thousands of published articles on the subject (14,892, to be exact). A lot of this work is theoretical, more of it is applied, and all of it focuses on an experience that is common to everybody. I was particularly impressed by an article by Evans, Boggero, and Segerstrom (2016) that illuminates the connections between physical and psychological factors, and specifically addresses “how fatigue can occur even in the presence of sufficient resources.” In fact, I read their article as providing evidence that fatigue usually occurs in the presence of sufficient resources – it’s not primarily a physical phenomenon at all; it’s a psychological one. This fact has many important implications. Fascinating stuff.
The related phenomena demonstrated by many, many studies of “ego depletion” are real, and important, and I personally have no doubt whatsoever about that. When people are tired, including psychologically tired (an interesting concept in its own right), their self-control abilities wane, prepotent responses (such as emotional lashing out, simplistic thinking, overlearned habits, selfish impulses) tend to take over as conscious control weakens. Isn’t that pretty much what the studies show, in the aggregate? Does anybody doubt that really happens? Has anybody out there honestly not experienced exactly these phenomena?
So why the controversy and doubt? Was it sparked by incompetent researchers with nefarious motives? No, at least, not at first. The controversy arose as one of many effects of the emergence of the replication crisis, which created an overall skepticism about many findings in social psychology, not just, or especially, ego depletion. Doubts about famous and even beloved social psychological findings first arose among researchers – many of them students – who became dismayed to discover that the neat-and-tidy looking JPSP articles they had read and admired reported findings that were surprisingly difficult to repeat in their own work. They certainly weren’t as easy to do as the JPSP articles would lead one to expect! I believe – and this is just a personal impression, but based on lots of conversations in hotel bars at professional meetings going back long before anybody was seriously talking about replication issues – that doubts about many classic social psychological findings first arose in people who loved the findings and wanted to do their own studies to extend them. Examples: elderly walking, “too much choice,” Lady Macbeth effect. These students and (mostly) young faculty, almost always concluded, at least at first, that they had done something wrong and they just couldn’t figure out what. It was only when they compared notes with other researchers (often at hotel bars), failures to replicate started to be talked about more publicly, and work like The Reproducibility Project (Open Science Collaboration, 2015) began to be conducted, that attitudes started to shift, and people who couldn’t make a study work – and, remember, it looked so easy in the JPSP article where, always, all four studies worked! – began to think: Maybe it’s not just me.
So, a few people started to go public with their doubts, and what happened next wasn’t pretty. Researchers who reported failures to replicate famous findings were told, by professors at Yale, Harvard and Princeton (respectively), that they had “nothing in their heads,” were “shameless little bullies” and even amounted to “methodological terrorists.” (These are exact quotes.) Were these failed replicators, coming under this kind of attack, going public in order to take an easy route towards building careers on bad research? It’s hard to think so, given the responses they got – which are reminiscent of what pretty much always happens to whistleblowers.
And there was plenty to blow the whistle about. Mostly, and most obviously, overclaiming. Go back and re-read what researchers on behavioral priming used to say (maybe they still do) about how powerfully subtle cues can completely derail our behavior without our knowing it, or others writing about “wise” interventions that, with tiny tweaks, can change a lifetime of behavioral habit. Or social psychologists (many, many of them) claiming that individual differences in personality (pet peeve alert) are so transient and weak that a quick situational manipulation can wipe them out. Oh really. Then why are these studies so hard to replicate, in the cases when they can be replicated at all?
The above two paragraphs capture about where I was, say, two years ago. But my views have shifted. First, I really did see, firsthand, a couple of places where the big replication projects were being carried out, and I have to say the methods used and quality control were, shall we say, far from optimal. My attitude shift was also catalyzed to a considerable degree by the experience I had when Kathleen Vohs invited me to participate in the SPSP presentation of her big, multi-site ego-depletion replication study (Funder, 2018). It motivated me to rethink the evaluation of effect sizes (culminating in the article I published recently with Dan Ozer; 2019), and to observe how the fundamental misunderstanding of these numbers bedevils psychological understanding in so many ways.
For example, original reports of many findings reported effects that were just way too large to be plausible (coupled with Ns too small to yield reliable effect size estimates). So, when others tried to replicate them, of course the same effect size wasn’t there, meaning their small-N study (which seemed like it should be enough, given the originally reported effect size) wasn’t significant, leading to the conclusion that “well, this phenomenon just doesn’t exist then.” No! Plausible effect sizes are what we too-blindly were conditioned over the years to regard as “small.” We still need to learn: Real effects are “small” effects, and so we need to rethink what we consider as small. And, while we’re at it, let’s recalibrate our views of the N and precision needed to decide that something doesn’t exist. I won’t go on about that here; Dan Ozer and I wrote about this in some detail, and Dan understands it on a deeper level than I do.
One other lesson I picked up from my experience at Kathleen’s SPSP symposium was less scientific and more disheartening. Some people were rooting for ego depletion to fail. They really were. I saw it on the Twitter. Some of my erstwhile friends and allies were “disappointed” (read: angry) with me for saying I think the effect is real, albeit “small,” and important. Unlike the very beginning of the replication controversy, which I think was characterized by disappointment and confusion, now it is increasingly characterized by skepticism bordering on cynicism, combined, in some cases, with a detectable smidgen of self-righteousness and even schadenfreude. [Insert the necessary qualifications, exceptions, and disavowals here. Certainly, since you are reading this essay, I don’t mean you, of all people. But there are some others out there who come close to meeting this description.]
And to say one more thing about ego depletion, specifically (because most of this little essay really concerns replication concerns in social psychology more broadly, not ego depletion): The boon and bane of the research program was and is its label. As a (semi-closeted) admirer of Freud, I’ve seen how just using the word “ego” is like the proverbial red flag in front of a bull for certain of our colleagues (none of whom know anything about Freud, by the way, but that’s another story). Calling the phenomenon “ego depletion” got the work tons of attention but also, I suspect, made it a big, fat target. Nobody can sensibly doubt that people get mentally and even morally tired. But the word “ego” just sets some people off. If the phenomenon had been called “psychological fatigue” from the very beginning, the research wouldn’t be so famous, and it wouldn’t have come under such intense fire.
Ok one more thing about ego depletion. I have noticed that Baumeister’s chapter in the Mele book – the one that stimulated this essay – does not attempt to defend – nor does it even mention – the glucose-related findings or theory, and indeed it seems that portion of the evidence has largely evaporated, and that part of the theory (in hindsight) was probably biologically implausible in the first place. This conclusion has contaminated views of ego depletion itself, leading to the impression the basic phenomenon is poorly supported or even doesn’t exist. Which is wrong, of course. I suspect the only way to rescue the topic is to dump the label. Psychological and moral fatigue is real and important. It should continue to be studied and better understood. Baumeister’s recent chapter says we should find out when it does and does not occur. Yup. That, and much more.
Baumeister, R.F. (2019). Self-control, ego depletion and social psychology’s replication crisis. Prepared for A. Mele (Ed.), Surrounding self-control. New York: Oxford. (Appendix to Chapter 2).
Evans, D.R., Boggero, I.A., & Segerstrom, S.C. (2016). The nature of self-regulatory failure and “ego depletion”: Lessons from physical fatigue. Personality and Social Psychology Review, 20, 291-310.
Funder, D.C. (2018, March). Implications of the depletion replication study for meta-science and behavioral research. Symposium presentation, Society for Personality and Social Psychology, Atlanta.
Funder, D.C., & Ozer, D.J. (2019). Evaluating effect size in psychological research: Sense and nonsense. Advances in Methods and Practices in Psychological Science, 2, 156-168.
Open Science Collaboration (2015). Estimating the reproducibility of psychological science. Science, 349, (6251).