Desirable Difficulties

Making learning a bit harder in the moment—creating desirable difficulties—forces your brain to work more actively, which typically creates stronger, more lasting memories. Smooth, easy learning often feels productive but can be superficial, leading you to forget the information quickly. For example, instead of just rereading your notes, trying to recall them from memory without looking (which feels harder) tends to lead to much better performance on a later test.

Try this: "Is this learning strategy just comfortable, or is it actually effective?"

Desirable difficulties work because they require more effortful mental processing. When your brain has to struggle to retrieve information or connect concepts, it builds stronger and more durable neural pathways for that knowledge, much like lifting weights builds muscle through resistance.

This principle isn't about making learning impossible; it's about introducing challenges that are manageable but prevent passive learning. Key techniques include:

• Spacing: Instead of cramming, spread your learning sessions out over time. Reviewing vocabulary for a new language for 15 minutes every day is far more effective than a single two-hour session.

• Interleaving: Mix up different but related topics during a study session. A basketball player who alternates practice between dribbling, shooting, and defense will develop more flexible skills than one who perfects each skill in isolation before moving on.

• Testing/Retrieval Practice: Actively try to recall information from memory. A manager preparing for a presentation who practices by trying to deliver it from memory, rather than just rereading slides, will both remember it better and identify gaps in their knowledge.

Coined by R.A. and E.L. Bjork, desirable difficulties are challenges that slow initial learning but tend to boost long-term retention and transfer. This effortful processing often builds more robust understanding than passive study. [1]

• A landmark review rated retrieval practice (testing) and distributed practice (spacing) as having high utility for learners across many contexts. [2] (2013)

• The testing effect is robust: a meta-analysis suggests testing is typically superior to restudying for long-term retention. [3, 4] [3] (2014)

• Interleaving (mixing) different topics or skills during practice tends to improve later performance compared to blocked (one-at-a-time) practice. [5] (2007)

The difficulty must be 'desirable' and calibrated to the learner's skill level; excessive difficulty can cause frustration. The benefits are primarily for long-term retention. For immediate performance, easier methods sometimes create an 'illusion of mastery' that often fades quickly.