Dr Robert Bjork, a cognitive psychologist coined a term back in 1994 called desirable difficulty. He suggested that introducing certain difficulties into the learning process greatly improved long-term retention.
The reason Bjork refers to the term ‘desirable’ is because having access to long term knowledge is the goal of most forms of learning. The term ‘difficulty’ however is not simply about making the process of learning harder but refers to the fact it has several difficult side effects. For example, it will slow down student progression and may result in the student feeling as if they are not learning efficiently or effectively. And that means they become unhappy with the subject and the teaching.
In essence ‘desirable difficulty’ refers to a learning task that may prove difficult initially but that leads to greater learning over an extended period of time.
How to make something more difficult?
The reason making something difficult works is because it impacts the encoding, storage and retrieval process. If something requires some degree of effort to encode it will be easier to retrieve, if it’s easy to encode, it is merely stored for the short term and as a result easily forgotten.
But just because something is difficult doesn’t mean it is desirably difficult. Bjork suggests a number of ways in which difficulties should be introduced.
Spacing learning and interleaving – study in small chunks, then either take a break or study another topic or subject, that’s the interleaving. Doing this is inefficient and will result in taking more time but it should help you retain the knowledge for the long term.
It highlights an important difference between tuition, and revision. Don’t leave the learning part until the last minute, chip away at it day by day, little and often. But when you get to revision, then cram as hard as you can. The cramming may not help with long term retention but it will get you through the exam. The number of students who come out of an exam having crammed for days, that can’t remember what was on the exam paper let alone what they have learned is evidence that Bjork does have a point.
Testing – controversial in some circles but testing to learn is not fundamentally wrong, it’s the implications and environment of testing that gets it a bad press.
Which one of the following is best?
- Study Study Study Study – Test
- Study Study Study – Test Test
- Study Study – Test Test Test
- Study – Test Test Test Test
The answer is number 4. Ideally make testing part of your practice, nothing to complicated though, low-key and very frequent. This will as before slow you down and many students will skip the tests they were asked to complete in favour of consuming more content, which is logical, just not the right thing to do for long term retention.
“Varying the context, examples, and problem type engages processes that can lead to a richer and more elaborated encoding of concepts and ideas, which can, in turn, support transfer of that learning to new settings.” Bjork
Having learners generate target material – This will not be liked by many, especially if you’re in full employment and time poor. And yet one of the most powerful learning techniques is to teach someone else, so it’s not that much of a surprise that preparing material to help teach yourself or another will help.
There are other techniques that Bjork suggests but they are a little more challenging, for example his research shows that making learning materials less well organised and more difficult to read is also effective. There is however a balance that needs to be struck between having a problem that when resolved will embed knowledge verses the time and frustration you might experience in going through the process.
Making something more difficult seems counterintuitive to me. I have spent much of my career trying to make the complicated seem easy. But this is not about making concepts difficult it’s the recognition that ultimately learning requires effort, and if that effort is directed towards a more effective way to learn, better long term learning will result.
If you want to hear more listen to this interview with Robert Bjork, it’s only just over 5m and well worth it.