- Title: Germane processes moderate the effectiveness of complex desirable difficulty tasks
- Authors: Ines Zeitlhofer & Joerg Zumbach
- Access the original paper here
- Watch a video overview:
Paper summary
Two influential ideas about task design pull in different directions. Cognitive load theory suggests raising complexity gradually; desirable difficulty theory suggests making practice harder, for example by mixing topics rather than blocking them. This Austrian experiment tested both at once. 132 adults with no Italian spent an hour learning to conjugate one Italian verb across six tenses and modal forms, randomly assigned to one of four versions of the task. Two days later, they sat a posttest. Those who had worked at constantly high complexity, and those whose practice was interleaved, solved it faster and with fewer attempts. The hardest combination did best and the easiest did worst. Interest and confidence were unaffected.
If teachers remember one thing from this study, it should be…
The easiest version of a task is not the kindest one. Learners kept at full complexity, and those whose practice mixed topics rather than blocking them, performed better two days later. Their interest and their confidence in themselves did not suffer for it.
*** PAPER DEEP DIVE ***
What are the key technical terms used in the paper?
- Interleaved practice: mixing topics within a session instead of blocking (drilling one topic before moving on).
- Desirable difficulties: task designs that feel harder but aid long-term memory.
- Cognitive load: the demand a task places on working memory.
- Germane processes: the mental effort learners invest in understanding a task.
What are the characteristics of the participants in the study?
132 adults recruited from Austrian universities, almost all students (97.73%), mean age 32.05 years. Eighty-six were female, 42 male and one non-binary. Anyone with basic Italian, or studying romance languages, was excluded. Participants were randomly assigned to one of four versions of the learning task.
What does this paper add to the current field of research?
Cognitive load theory and desirable difficulty theory are each well evidenced on their own, yet they give conflicting design advice and have rarely been tested against each other. This is among the first experiments to cross the two, and to ask whether the resulting difficulty carries a motivational cost.
What are the key implications for teachers in the classroom?
- Starting easy and building up may not be the safest default. Half the learners assigned every verb ending from the first exercise; the other half started with one ending and added more as they went. Everyone covered the same material in the same time. The group held at full complexity throughout finished the delayed test faster and with fewer attempts. If your class already has the prerequisites, consider giving them the whole version of the task from the outset rather than a carefully graded ladder up to it.
- Mix the practice set rather than blocking it. Learners who met all six verb forms in a shuffled order each round outperformed those who drilled one form at a time. The classroom move is small and free: instead of ten questions on one method followed by ten on another, shuffle them, so students have to work out which method a question calls for before they can use it.
- Check whether practice worked days later, not minutes later. The whole benefit here showed up on a test two days after the learning session. Performance at the end of a lesson tells you how fluently students can repeat something while it is still fresh. A short low-stakes retrieval task at the start of the next lesson, or the following week, is a truer read on whether it stuck.
- Difficulty is not the same as being left to flounder. These learners were given the full table of verb endings to refer to, got immediate right or wrong feedback on every attempt, and moved on automatically after a minute. The difficulty sat in the thinking, not in the guessing. The authors are explicit that this only works when learners have enough prior knowledge to get purchase on the task, so the judgement call is whether the challenge is demanding or simply impossible.
- Don’t assume harder work will flatten motivation. A reasonable worry about all of this is that students will find it dispiriting. In this study it did not happen: interest in the task and belief in their own chances of success were no lower in the hard conditions than in the easy ones. That said, these were adult volunteers on a one-hour task, so treat this as encouragement to try rather than a guarantee about a whole term.
Why might teachers exercise caution before applying these findings in their classroom?
These were adult volunteers, average age 32, learning Italian verb endings in a lab for an hour. Performance meant speed and number of attempts, not accuracy, and was measured once, two days later. The authors note their findings come from a single experiment in one narrow domain.
What is a single quote that summarises the key findings from the paper?
“Findings of the present study suggest that manipulating tasks in a way that allows them to be easily solved might underestimate a learner’s cognitive potential.”
