The Backfire Effect is NOT Prevalent: Good News for Debunkers, Humans, and Learning Professionals!

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An exhaustive new research study reveals that the backfire effect is not as prevalent as previous research once suggested. This is good news for debunkers, those who attempt to correct misconceptions. This may be good news for humanity as well. If we cannot reason from truth, if we cannot reliably correct our misconceptions, we as a species will certainly be diminished—weakened by realities we have not prepared ourselves to overcome. For those of us in the learning field, the removal of the backfire effect as an unbeatable Goliath is good news too. Perhaps we can correct the misconceptions about learning that every day wreak havoc on our learning designs, hurt our learners, push ineffective practices, and cause an untold waste of time and money spent chasing mythological learning memes.



The Backfire Effect

The backfire effect is a fascinating phenomenon. It occurs when a person is confronted with information that contradicts an incorrect belief that they hold. The backfire effect results from the surprising finding that attempts at persuading others with truthful information may actually make the believer believe the untruth even more than if they hadn’t been confronted in the first place.

The term “backfire effect” was coined by Brendan Nyhan and Jason Reifler in a 2010 scientific article on political misperceptions. Their article caused an international sensation, both in the scientific community and in the popular press. At a time when dishonesty in politics seems to be at historically high levels, this is no surprise.

In their article, Nyhan and Reifler concluded:

“The experiments reported in this paper help us understand why factual misperceptions about politics are so persistent. We find that responses to corrections in mock news articles differ significantly according to subjects’ ideological views. As a result, the corrections fail to reduce misperceptions for the most committed participants. Even worse, they actually strengthen misperceptions among ideological subgroups in several cases.”

Subsequently, other researchers found similar backfire effects, and notable researchers working in the area (e.g., Lewandowsky) have expressed the rather fatalistic view that attempts at correcting misinformation were unlikely to work—that believers would not change their minds even in the face of compelling evidence.


Debunking the Myths in the Learning Field

As I have communicated many times, there are dozens of dangerously harmful myths in the learning field, including learning styles, neuroscience as fundamental to learning design, and the myth that “people remember 10% of what they read, 20% of what they hear, 30% of what they see…etc.” I even formed a group to confront these myths (The Debunker Club), although, and I must apologize, I have not had the time to devote to enabling our group to be more active.

The “backfire effect” was a direct assault on attempts to debunk myths in the learning field. Why bother if we would make no difference? If believers of untruths would continue to believe? If our actions to persuade would have a boomerang effect, causing false beliefs to be believed even more strongly? It was a leg-breaking, breath-taking finding. I wrote a set of recommendations to debunkers in the learning field on how best to be successful in debunking, but admittedly many of us, me included, were left feeling somewhat paralyzed by the backfire finding.

Ironically perhaps, I was not fully convinced. Indeed, some may think I suffered from my own backfire effect. In reviewing a scientific research review in 2017 on how to debunk, I implored that more research be done so we could learn more about how to debunk successfully, but I also argued that misinformation simply couldn’t be a permanent condition, that there was ample evidence to show that people could change their minds even on issues that they once believed strongly. Racist bigots have become voices for diversity. Homophobes have embraced the rainbow. Religious zealots have become agnostic. Lovers of technology have become anti-technology. Vegans have become paleo meat lovers. Devotees of Coke have switched to Pepsi.

The bottom line is that organizations waste millions of dollars every year when they use faulty information to guide their learning designs. As a professional in the learning field, it’s our professional responsibility to avoid the danger of misinformation! But is this even possible?


The Latest Research Findings

There is good news in the latest research! Thomas Wood and Ethan Porter just published an article (2018) that could not find any evidence for a backfire effect. They replicated the Nyhan and Reifler research, they expanded tenfold the number of misinformation instances studied, they modified the wording of their materials, they utilized over 10,000 participants in their research, and they varied their methods for obtaining those participants. They did not find any evidence for a backfire effect.

“We find that backfire is stubbornly difficult to induce, and is thus unlikely to be a characteristic of the public’s relationship to factual information. Overwhelmingly, when presented with factual information that corrects politicians—even when the politician is an ally—the average subject accedes to the correction and distances himself from the inaccurate claim.”

There is additional research to show that people can change their minds, that fact-checking can work, that feedback can correct misconceptions. Rich and Zaragoza (2016) found that misinformation can be fixed with corrections. Rich, Van Loon, Dunlosky, and  Zaragoza (2017) found that corrective feedback could work, if it was designed to be believed. More directly, Nyhan and Reifler (2016), in work cited by the American Press Institute Accountability Project, found that fact checking can work to debunk misinformation.


Some Perspective

First of all, let’s acknowledge that science sometimes works slowly. We don’t yet know all we will know about these persuasion and information-correction effects.

Also, let’s please be careful to note that backfire effects, when they are actually evoked, are typically found in situations where people are ideologically inclined to a system of beliefs for which they strongly identify. Backfire effects have been studied most of in situations where someone identifies themselves as a conservative or liberal—when this identity is singularly or strongly important to their self identity. Are folks in the learning field such strong believers in a system of beliefs and self-identity to easily suffer from the backfire effect? Maybe sometimes, but perhaps less likely than in the area of political belief which seems to consume many of us.

Here are some learning-industry beliefs that may be so deeply held that the light of truth may not penetrate easily:

  • Belief that learners know what is best for their learning.
  • Belief that learning is about conveying information.
  • Belief that we as learning professionals must kowtow to our organizational stakeholders, that we have no grounds to stand by our own principles.
  • Belief that our primary responsibility is to our organizations not our learners.
  • Belief that learner feedback is sufficient in revealing learning effectiveness.

These beliefs seem to undergird other beliefs and I’ve seen in my work where these beliefs seem to make it difficult to convey important truths. So let me clarify and first say that it is speculative on my part that these beliefs have substantial influence. This is a conjecture on my part. Note also that given that the research on the “backfire effect” has now been shown to be tenuous, I’m not claiming that fighting such foundational beliefs will cause damage. On the contrary, it seems like it might be worth doing.


Knowledge May Be Modifiable, But Attitudes and Belief Systems May Be Harder to Change

The original backfire effect showed that people believed facts more strongly when confronted with correct information, but this misses an important distinction. There are facts and there are attitudes, belief systems, and policy preferences.

A fascinating thing happened when Wood and Porter looked for—but didn’t find—the backfire effect. They talked with the original researchers, Nyhan and Reifler, and they began working together to solve the mystery. Why did the backfire effect happen sometimes but not regularly?

In a recent podcast (January 28, 2018) from the “You Are Not So Smart” podcast, Wood, Porter, and Nyhan were interviewed by David McRaney and they nicely clarified the distinction between factual backfire and attitudinal backfire.


“People often focus on changing factual beliefs with the assumption that it will have consequences for the opinions people hold, or the policy preferences that they have, but we know from lots of social science research…that people can change their factual beliefs and it may not have an effect on their opinions at all.”

“The fundamental misconception here is that people use facts to form opinions and in practice that’s not how we tend to do it as human beings. Often we are marshaling facts to defend a particular opinion that we hold and we may be willing to discard a particular factual belief without actually revising the opinion that we’re using it to justify.”


“Factual backfire if it exits would be especially worrisome, right? I don’t really believe we are going to find it anytime soon… Attitudinal backfire is less worrisome, because in some ways attitudinal backfire is just another description for failed persuasion attempts… that doesn’t mean that it’s impossible to change your attitude. That may very well just mean that what I’ve done to change your attitude has been a failure. It’s not that everyone is immune to persuasion, it’s just that persuasion is really, really hard.”

McRaney (Podcast Host):

“And so the facts suggest that the facts do work, and you absolutely should keep correcting people’s misinformation because people do update their beliefs and that’s important, but when we try to change people’s minds by only changing their [factual] beliefs, you can expect to end up, and engaging in, belief whack-a-mole, correcting bad beliefs left and right as the person on the other side generates new ones to support, justify, and protect the deeper psychological foundations of the self.”


“True backfire effects, when people are moving overwhelmingly in the opposite direction, are probably very rare, they are probably on issues where people have very strong fixed beliefs….”


Rise Up! Debunk!

Here’s the takeaway for us in the learning field who want to be helpful in moving practice to more effective approaches.

  • While there may be some underlying beliefs that influence thinking in the learning field, they are unlikely to be as strongly held as the political beliefs that researchers have studied.
  • The research seems fairly clear that factual backfire effects are extremely unlikely to occur, so we should not be afraid to debunk factual inaccuracies.
  • Persuasion is difficult but not impossible, so it is worth making attempts to debunk. Such attempts are likely to be more effective if we take a change-management approach, look to the science of persuasion, and persevere respectfully and persistently over time.

Here is the message that one of the researchers, Tom Wood, wants to convey:

“I want to affirm people. Keep going out and trying to provide facts in your daily lives and know that the facts definitely make some difference…”

Here are some methods of persuasion from a recent article by Flynn, Nyhan, and Reifler (2017) that have worked even with people’s strongly-held beliefs:

  • When the persuader is seen to be ideologically sympathetic with those who might be persuaded.
  • When the correct information is presented in a graphical form rather than a textual form.
  • When an alternative causal account of the original belief is offered.
  • When credible or professional fact-checkers are utilized.
  • When multiple “related stories” are also encountered.

The stakes are high! Bad information permeates the learning field and makes our learning interventions less effective, harming our learners and our organizations while wasting untold resources.

We owe it to our organizations, our colleagues, and our fellow citizens to debunk bad information when we encounter it!

Let’s not be assholes about it! Let’s do it with respect, with openness to being wrong, and with all our persuasive wisdom. But let’s do it. It’s really important that we do!


Research Cited

Nyhan, B., & Reifler, J. (2010). When corrections fail: The persistence of political misperceptions.
Political Behavior, 32(2), 303–330.

Nyhan, B., & Zaragoza, J. (2016). Do people actually learn from fact-checking? Evidence from a longitudinal study during the 2014 campaign. Available at:
Rich, P. R., Van Loon, M. H., Dunlosky, J., & Zaragoza, M. S. (2017). Belief in corrective feedback for common misconceptions: Implications for knowledge revision. Journal of Experimental Psychology: Learning, Memory, and Cognition, 43(3), 492-501.
Rich, P. R., & Zaragoza, M. S. (2016). The continued influence of implied and explicitly stated misinformation in news reports. Journal of Experimental Psychology: Learning, Memory, and Cognition, 42(1), 62-74.
Wood, T., & Porter, E. (2018). The elusive backfire effect: Mass attitudes’ steadfast factual adherence, Political Behavior, Advance Online Publication.


Big Data and Learning — A Wild Goose Chase?

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Geese are everywhere these days, crapping all over everything. Where we might have nourishment, we get poop on our shoes.

Big data is everywhere these days…

Even flocking into the learning field.

For big-data practitioners to NOT crap up the learning field, they’ll need to find good sources of data (good luck with that!), use intelligence about learning to know what it means (blind arrogance will prevent this, at least at first), and then find where the data is actually useful in practice (will there be patience and practice or just shiny new objects for sale?).

Beware of the wild goose chase! It’s already here.

Guest Post from Robert O. Brinkerhoff: 70-20-10: The Good, the Bad, and the Ugly

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This is a guest post by Robert O. Brinkerhoff (

Rob is a renowned expert on learning evaluation and performance improvement. His books, Telling Training’s Story and Courageous Training, are classics.


70-20-10: The Good, the Bad, and the Ugly

The 70-20-10 framework may not have much if any research basis, but it is still a good reminder to all of us in in the L&D and performance improvement professions that the work-space is a powerful teacher and poses many opportunities for practice, feedback, and improvement.

But we must also recognize that a lot of the learning that is taking place on the job may not be for the good. I have held jobs in agencies, corporations and the military where I learned many things that were counter to what the organization wanted me to learn: how to fudge records, how to take unfair advantage of reimbursement policies, how to extend coffee breaks well beyond their prescribed limits, how to stretch sick leave, and so forth.

These were relatively benign instances. Consider this: Where did VW engineers learn how to falsify engine emission results? Where did Well Fargo staff learn how to create and sell fake accounts to their unwitting customers?

Besides these egregiously ugly examples, we have to also recognize that in the case of L&D programming that is intended to support new strategic and other change initiatives, the last thing the organization needs is more people learning how to do their jobs in the old way. AT&T, for example, worked very hard to drive new beliefs and actions to enable the business to shift from landline technologies to wireless; on-the-job learning dragged them backwards, and creates problems still today. As AllState Insurance tries to shift sales focus away from casualty policies to financial planning services, the old guard teaches the opposite actions, as they continue to harvest the financial benefits of policy renewals. Any organization that has to make wholesale and fundamental shifts to execute new strategies will have to cope with the negative effects of years of on-the-job learning.

When strategy is new, there are few if any on-the-job pockets of expertise and role models. Training new employees for existing jobs is a different story. Here, obviously, the on-job space is an entirely appropriate learning resource.

In short, we have to recognize that not all on-the-job learning is learning that we want. Yet on the job learning remains an inexorable force that we in L&D must learn how to understand, leverage, guide and manage.

Purpose of Workplace Learning and Development. Survey Inquiry

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Seek Research-to-Practice Experts as Your Trusted Advisors

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I added these words to the sidebar of my blog, and I like them so much that I’m sharing them as a blog post itself.

Please seek wisdom from research-to-practice experts — the dedicated professionals who spend time in two worlds to bring the learning field insights based on science. These folks are my heroes, given their often quixotic efforts to navigate through an incomprehensible jungle of business and research obstacles.

These research-to-practice professionals should be your heroes as well. Not mythological heroes, not heroes etched into the walls of faraway mountains. These heroes should be sought out as our partners, our fellow travelers in learning, as people we hire as trusted advisors to bring us fresh research-based insights.

The business case is clear. Research-to-practice experts not only enlighten and challenge us with ideas we might not have considered — ideas that make our learning efforts more effective in producing business results — research-to-practice professionals also prevent us from engaging in wasted efforts, saving our organizations time and money, all the while enabling us to focus more productively on learning factors that actually matter.

Will Thalheimer Interviewed on HRD TV in Belgium


I had the great pleasure of being invited to provide a keynote in Leuven, Belgium at the VOV Congress. There were two highlights in my day, my keynote and being interviewed on HRD TV by Sandra De Milliano.

Audience members asked me questions and I did my best to answer them. We had questions about elearning, microlearning, PowerPoint, learning styles, rewards for learners, the spacing effect, remembering and application, and more.

Take a look…

Getting Better Responses on Your Smile Sheets.


One of the most common questions I get when I speak about the Performance-Focused Smile-Sheet approach (see the book’s website at is “What can be done to get higher response rates from my smile sheets?”

Of course, people also refer to smile sheets as evals, level 1’s, happy sheets, hot or warm evaluation, response forms, reaction forms, etc. They also refer to both paper-and-pencil forms and online surveys. Indeed, as smile sheets go online, more and more people are finding that online surveys get a much lower response rate than in-classroom paper surveys.

Before I give you my list for how to get a higher response rate, let me blow this up a bit. The thing is, while we want high response rates, there’s something much more important than response rates. We also want response relevance and precision. We want the questions to relate to learning effectiveness, not just learning reputation and learner satisfaction. We also want the learners to be able to answer the questions knowledgeably and give our questions their full attention.

If we have bad questions — one’s that use Likert-like or numeric scales for example — it won’t matter that we have high response rates. In this post, I’m NOT going to focus on how to write better questions. Instead, I’m just tackling how we can motivate our learners to give our questions more of their full attention, thus increasing the precision of their responding while also increasing our response rates as well.

How to get Better Responses and Higher Response Rates

  1. Ask with enthusiasm, while also explaining the benefits.
  2. Have a trusted person make the request (often an instructor who our learners have bonded with).
  3. Mention the coming smile sheet early in the learning (and more than once) so that learners know it is an integral part of the learning, not just an add-on.
  4. While mentioning the smile sheet, let folks know what you’ve learned from previous smile sheets and what you’ve changed based on the feedback.
  5. Tell learners what you’ll do with the data, and how you’ll let them know the results of their feedback.
  6. Highlight the benefits to the instructor, to the instructional designers, and to the organization. Those who ask can mention how they’ve benefited in the past from smile sheet results.
  7. Acknowledge the effort that they — your learners — will be making, maybe even commiserating with them that you know how hard it can be to give their full attention when it’s the end of the day or when they are back to work.
  8. Put the time devoted to the survey in perspective, for example, “We spent 7 hours today in learning, that’s 420 minutes, and now we’re asking you for 10 more minutes.”
  9. Ensure your learners that the data will be confidential, that the data is aggregated so that an individual’s responses are never shared.
  10. Let your learners know the percentage of people like them who typically complete the survey (caveat: if it’s relatively high).
  11. Use more distinctive answer choices. Avoid Likert-like answer choices and numerical scales — because learners instinctively know they aren’t that useful.
  12. Ask more meaningful questions. Use questions that learners can answer with confidence. Ask questions that focus on meaningful information. Avoid obviously biased questions — as these may alienate your learners.

How to get Better Responses and Higher Response Rates on DELAYED SMILE SHEETS

Sometimes, we’ll want to survey our learners well after a learning event, for example three to five weeks later. Delayed smile sheets are perfectly positioned to find out more about how the learning is relevant to the actual work or to our learners’ post-learning application efforts. Unfortunately, prompting action — that is getting learners to engage our delayed smile sheets — can be particularly difficult when asking for this favor well after learning. Still, there are some things we can do — in addition to the list above — that can make a difference.

  1. Tell learners what you learned from the end-of-learning smile sheet they previously completed.
  2. Ask the instructor who bonded with them to send the request (instead of an unknown person from the learning unit).
  3. Send multiple requests, preferably using a mechanism that only sends these requests to those who still need to complete the survey.
  4. Have the course officially end sometime AFTER the delayed smile sheet is completed, even if that is largely just a perception. Note that multiple-event learning experiences lend themselves to this approach, whereas single-event learning experiences do not.
  5. Share with your learners a small portion of the preliminary data from the delayed smile sheet. “Already, 46% of your fellow learners have completed the survey, with some intriguing tentative results. Indeed, it looks like the most relevant topic as rated by your fellow learners is… and the least relevant is…”
  6. Share with them the names or job titles of some of the people who have completed the survey already.
  7. Share with them the percentage of folks from his/her unit who have responded already or share a comparison across units.

What about INCENTIVES?

When I ask audiences for their ideas for improving responses and increasing response rates, they often mention some sort of incentive, usually based on some sort of lottery or raffle. “If you complete the survey, your name will be submitted to have chance to win the latest tech gadget, a book, time off, lunch with an executive, etc.”

I’m a skeptic. I’m open to being wrong, but I’m still skeptical about the cost/benefit calculation. Certainly for some audiences an incentive will increase rates of completion. Also, for some audiences, the harms that come with incentives may be worth it.

What harms you might ask? When we provide an external incentive, we might be sending a message to some learners that we know the task has no redeeming value or is tedious or difficult. People who see their own motivation as caused by the external incentive are potentially less likely to seriously engage our questions, producing bad data. We’re also not just having an effect on the current smile sheet. When we incentivize people today, they may be less willing next time to engage in answering our questions. They may also be pushed into believing that smile sheets are difficult, worthless, or worse.

Ideally, we’d like our learners to want to provide us with data, to see answering our questions as a worthy and helpful exercise, one that is valuable to them, to us, and to our organization. Incentives push against this vision.


Doing Research On Our Learning Products


The learning profession has been blessed in recent years with a steady stream of scientific research that points to practical recommendations for designers of learning. If you or your organization are NOT hooked into the learning research, find yourself a research translator to help you! Call me, for example!

That’s the good news, but I have bad news for you too. In the old days, it wasn’t hard to create a competitive advantage for your company by staying abreast of the research and using it to design your learning products and services. Pretty soon, that won’t be enough. As the research becomes more widely known, you’ll have to do more to get a competitive advantage. Vendors especially will have to differentiate their products — NOT just by basing them on the research — but also by conducting research (A-B testing at a minimum) on your own products.

I know of at least a few companies right now who are conducting research on their own products. They aren’t advertising their research, because they want to get a jumpstart on the competition. But eventually, they’ll begin sharing what they’ve done.

Do you need an example of a company who’s had their product tested? Check out this page. Scroll down to the bottom and look at the 20 or so research studies that have been done using the product. Looks pretty impressive right?

To summarize, there are at least five benefits to doing research on your own products:

  1. Gain a competitive advantage by learning to make your product better.
  2. Gain a competitive advantage by supporting a high-quality brand image.
  3. Gain a competitive advantage by enabling the creation of unique and potent content marketing.
  4. Gain a competitive advantage by supporting creativity and innovation within your team.
  5. Gain a competitive advantage by creating an engaging and learning-oriented team environment.

Definition of MicroLearning

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I’ve looked for a good definition of microlearning, but because I couldn’t find one, I’ve created my own.

Microlearning involves the use of:

“Relatively short engagements in learning-related activities—typically ranging from a few seconds up to 20 minutes (or up to an hour in some cases)—that may provide any combination of content presentation, review, practice, reflection, behavioral prompting, performance support, goal reminding, persuasive messaging, task assignments, social interaction, diagnosis, coaching, management interaction, or other learning-related methodologies.”

Microlearning has five utilization cases:

  1. Course Replacement
    Provides training content and learning support, often as a replacement for classroom training or long-form elearning.
  2. Course Augmentation
    Provides after-course or within-course streams of short learning interactions to reinforce, strengthen, or deepen learning.
  3. Retrieval Support
    Provides retrieval practice, spaced repetitions, and reminding to ensure knowledge and skills can be remembered when needed.
  4. Just-In-Time (Moment-of-Need) Learning
    Provides information when learners need it to perform a task they are working on.
  5. Behavioral Prompts
    Provides action nudges, task assignments, or performance support to directly prompt and support behavior.

If it’s not obvious, there are clearly overlaps in these five use cases, and furthermore, a single microlearning thread may utilize more than one of the methodologies suggested. For example, when using microlearning as a replacement for a standard elearning course, you might also consider retrieval support and behavioral prompts in your full learning design.

Will’s History of Spacing Out on Learning


As you know, if you’ve dabbled into my work for a few years, I’ve closely followed the research finding, “The Spacing Effect,” both from a research perspective and a practical perspective. Indeed, I was one of the first in the workplace learning field to recognize its practical significance, which I wrote about as early as 2002. In 2006 I published the research-to-practice report entitled Spacing Learning Over Time, which should — if there was justice in the world (LOL) or viable trade organizations (OUCH) — be enshrined in the Learning and Development Hall of Fame. Snickers are welcome. Taza Chocolate even better. A few years ago, still wanting to advocate for the practical use of the spacing effect, I began speaking about Subscription Learning at conferences and I developed a website ( to encourage folks in the learning field to utilize the spacing effect in their learning designs. is being retired in 2017, as it is no longer needed. Blog posts from the website are incorporated in this blog.

I am grateful to the enlightened organizations who have supported my work over the years and specifically to the individuals who continue to encourage the reading of the 2006 research report. Feel free to share yourself.

Now in 2017, I am grateful to another organization, Learning Technologies (in the UK) who is sponsoring me to speak on the spacing effect at their conference starting in a few weeks. As part of my efforts, I am developing a new presentation and I am updating my research compilation on the spacing effect. Stay tuned to this blog as I’m likely to share a few of my findings as I dig into the research.

Indeed, the research on spacing is some of the most interesting I’ve studied over the years. The first thing that fascinates is that there is so much damn research on the spacing effect, also referred to as spaced learning, distributed practice, and interleaving. In 1992, Bruce and Bahrick counted up the number of scientific studies on spacing and found over 300 articles at that time. Every year, there are more and more scientific articles published on spacing. By my rough count of journal articles cited on PsycINFO (a primary social-science database), over the last three years there have been 31 new articles published on the spacing effect (7 in 2014, 14 in 2015, and 10 in 2016).

One of the main reasons that so many research articles are published on the spacing effect is that the phenomenon is so intriguing. Why would spacing repetitions over time produce so much more remembering than giving the learners the exact same repetitions but simply massing them all at once or spacing them with less time in between? Freakin’ fascinating! So researchers keep digging into the complexities.

Harry Bahrick and Lynda Hall announced in 2005 that, “The spacing effect is one of the oldest and best documented phenomena in the history of learning and memory research.” And, just last year in a scientific review article, Geoffrey Maddox wrote, Because of its robustness, the spacing effect has the potential to be applied across a variety of contexts as a way of improving learning and memory.”

Stay tuned, as I hope to be be spacing my research compilations over time…


Bahrick, H. P., & Hall, L. K. (2005). The importance of retrieval failures to long-term retention: A metacognitive explanation of the spacing effect. Journal of Memory and Language, 52, 566-577.

Maddox, G. B. (2016). Understanding the underlying mechanism of the spacing effect in verbal learning: A case for encoding variability and study-phase retrieval. Journal of Cognitive Psychology, 28(6), 684-706.

Thalheimer, W. (2006, February). Spacing Learning Events Over Time: What the Research Says. Available at: