Despite a heavy focus on cognitive psychology in the way I researched and explained classroom study tactics, I had not encountered the phrase desirable difficulty until I became interested in the handwritten vs. keyboard notetaking research. I discovered the idea when reviewing studies by Luo and colleagues and Mueller and Oppenheimer. Several studies have claimed students are better off taking notes by hand in comparison to on a laptop despite being able to record information significantly faster when using a keyboard.
Since having a more complete set of notes would seem an advantage. The combination of more notes associated with poorer performance is counterintuitive. Researchers speculated that learners who understood they had to make decisions about what they had time to record selected information more carefully and possibly summarized rather than recorded verbatim what they heard. This focus on what could be described as deeper processing seemed like an example of desirable difficulty. The researchers also proposed that the faster keyboard recording involved shallow cognitive processing.
Note: I am still a fan of more complete notes and the methodology used when demonstrating better performance from recording notes by hand needs to be carefully considered. I will comment on my argument more at the end of this post.
Desirable difficulty an idea attributed to Robert Bjork has been used to explain a wider variety of retention phenomena. Bjork suggested that retrieval strength and storage strength are distinct phenomena and learners can be misled when an approach to learning is evaluated based on retrieval strength. I find these phrases to a bit confusing as applied, but I understand the logic. Students cramming for an exam make a reasonable example. Cramming results in what may seem to be successful learning (retrieval strength), but results in poorer retention over an extended period of time (storage storage strength). Students may understand and accept the disadvantages of cramming so it is not necessary that the distinction be unrecognized by learners. In a more recent book on learning for the general public, Daniel Willingham suggests that the brain is really designed to avoid rather than embrace thinking because thinking is effortful. The human tendency is to rely on memory rather than thinking. Desirable difficulty may be a way to explain why some situations that require thinking prevent something more rote.
Increasing difficulty to improve retention
There are multiple tactics for productively increasing difficulty that I tend to group under the heading of generative learning. I describe generative activities as external tasks intended to increase the probability of productive cognitive (mental) behaviors. I suppose desirable difficulty is even more specific differentiating external tasks along a difficulty dimension. So in the following list of tasks, it is useful to imagine more and less difficult tasks. Often the less difficult task is the option learners choose to apply. In connecting these tactics with personal experience, I would recommend you consider the use of flashcards to conceptualize what would be the easier and the more challenging application. Then, move beyond flashcards to other study tactics and consider if you can identify similar contrasts.
Retrieval Practice: Testing oneself on the material rather than passively reviewing notes is considered retrieval practice. The classic empirical demonstration of the retrieval practice or the testing effect compared reviewing content versus responding to questions. Even when controlling for study time, spending some time on questions was superior. With the flashcard applications I recommended you consider, answering multiple-choice questions would be less challenging than answering short-answer questions (recognition vs recall).
Spacing (Distributed Practice): Instead of cramming, spreading out study sessions over time is more productive. This method helps improve long-term retention and understanding. Spacing allows some retrieval challenges to develop and the learner must work harder to locate the desired information in memory. See my earlier description of Bjork’s distinction between retrieval strength and storage strength.
Interleaving: Mixing different types of problems or subjects in one study session. For example, alternating between math problems and reading passages rather than focusing on one at a time. A simple flashcard version of this recommendation might be shuffling the deck between cycles through the deck. Breaking up the pattern of the review task increases the difficulty and requires greater cognitive effort.
Other thoughts
First, the concept of committing to more challenging tasks is broader than the well researched examples I provide here. Writing and teaching could be considered examples in that both tasks require an externalization of knowledge that is both generative and evaluative. It is too easy to fake it and make assumptions when the actual creation of a product is not required.
Second, desirable difficulty seems to me to be a guiding principle that does not explain all of the actual cognitive mechanisms that are involved. The specific mechanisms may vary with activity – some might be motivational, some evaluative (metacomprehension), and some at the level of basic cognitive activities. For example, creating retrieval challenges probably creates an attempt to find alternate or new connections among stored elements of information. For example, in trying to put a name with a face one might attempt to remember the circumstances in which you may have met or worked with this person and this may activate a connection you do not typically use and is not automatic. For example, after being retired for 10 years and trying to remember the names of coworkers, I sometimes remember the arrangement of our offices working my way down the appropriate hallway and this sometimes helps me recall names.
I did say I was going to return to the use of desirable difficulty as a justification for the advantage of taking notes by hand. If keyboarding allows faster data entry than handwriting, in theory keyboarding would allow more time for thinking, paraphrasing, and whatever advantage one would have when the recording method requires more time. Awareness and commitment would seem to be the issues here. However, I would think complete notes would have greater long-term value than sparse notes. One always has the opportunity to think while studying and a more complete set of notes would seem to provide the opportunity to have more external content to work with.
References:
Bjork, R.A. (1994). Memory and metamemory considerations in the training of human beings. In J. Metcalfe & A. Shimamura (Eds.), Metacognition: Knowing about knowing (pp. 185-205). Cambridge, MA: MIT Press.
Luo, L., Kiewra, K. A., Flanigan, A. E., & Peteranetz, M. S. (2018). Laptop versus longhand note taking: effects on lecture notes and achievement. Instructional Science, 46(6), 947-971.
Mueller, P. A., & Oppenheimer, D. M. (2014). The pen is mightier than the keyboard: Advantages of longhand over laptop note taking. Psychological science, 25(6), 1159-1168.
Willingham, D. T. (2021). Why don’t students like school?: A cognitive scientist answers questions about how the mind works and what it means for the classroom. John Wiley & Sons.