Ebbinghaus: the Parrot Sketch

One of the most dispiriting things about working in learning is the lack of decent theoretical underpinnings. In such an environment it’s understandable that people will try and make use of whatever theories are available to justify a particular practice. I still attend conferences where people are using Kolb’s learning cycle, Honey & Mumford’s Learning Styles or Maslow’s Hierarchy of Needs to explain what they are doing. These approaches, whilst seductive, are now decades old and have been almost entirely discredited since their creation. They were all well-intentioned, but it is as if we forget that they were the first unsteady steps in a relatively new discipline.

There are some other notable additions to the usual suspects: Atkinson & Shiffrin’s ‘Stage Theory of Memory’ (1968) and Craik & Lockhart’s (1972) ‘Levels of Processing’ model. Both have intuitive appeal: the first suggests that we transfer items into long-term memory by repeating them (like we would a telephone number), the latter that processing something semantically is better than just looking at it or hearing it. But the first model predicts that if you gag a person they would be unable to remember anything, whilst the latter predicts that even a boring lecture is more memorable than being in a car accident. Both are misleading.

The study I would like to look at here, though, is that by Ebbinghaus (1885) – a study that I have been using over the last year to illustrate an important distinction between formal and informal learning (even though it’s actually completely unscientific by modern standards). Most commonly I use this work to illustrate the pattern of forgetting common to many formal learning contexts. Specifically, Ebbinghaus tried to learn completely meaningless lists of letters, then noticed that almost all of the information was forgotten very quickly.

The diagrams above illustrate two outcomes of Ebbinghaus’ experiments. The first is the well-known forgetting curve. 

The second shows how many repetitions he needed to relearn the list over time. It is possible to interpret this last study to mean that regular repetition of information – or even learning by rote - is the key to effective learning. This is not merely wrong, but a dangerous interpretation, supporting the case for ‘drilling’ students or encouraging them to learn ‘parrot fashion’. I’d like to explain why this is a misleading reading:

Ebbinghaus’ study is illustrative of something interesting, but not what one might expect. For the purposes of his study he tried to memorise ‘trigrams’ – random sequences of three letters (such as DYV). Since these were deliberately meaningless the results say almost nothing about natural/normal learning, since almost everything we learn is meaningful – indeed that is how we are designed (I can guess what he would find if one of the trigrams were FBI, for example – and if he actually experimented on participants). What Ebbinghaus demonstrated is that we are cognitive misers, i.e. that the mind rejects – or spits out - anything that is not useful/meaningful much as the human digestive tract would reject something indigestible. His experiment is roughly equivalent to feeding people glass beads. It does, of course, throw a critical light on formal learning, where people are indeed routinely force-fed large amounts of stuff which is not obviously significant to them – but, as I have argued elsewhere, conventional formal learning is a strange cultural practice that has little to do with learning – and basically we should stop doing it. I heard a similar point being made by Sir Ken Robinson on the TED site.

What is interesting about his work is that he begins to touch on the way that you can add meaning to information, namely by testing people. To put it crudely: the information before you may be meaningless but if I have you at gunpoint and you have to score 60% or more to live, then it is surprising how much you can memorise. People respond well to challenges – their self-esteem may be at stake, and sometimes their standing within a group. The mere act of being threatened with a test is what keeps much formal learning afloat. Since he was testing himself, there is little doubt he knew what was coming – and given that it was he was both experimenter and subject it is hard to imagine that the results lacked any personal significance.

So I think one should be careful about a reading of Ebbinghaus. It doesn’t really demonstrate that regular repetition is the golden path to learning – but rather that tests can give even meaningless stuff a kind of significance. I do think that if organisations want their employees to remember meaningless stuff then ‘apprentice’ style challenges would be a good way to do it. But then I think they shouldn’t really be getting employees to learn meaningless stuff in the first place (that’s why informal learning is 85% of the cake, after all). Or, to put it another way, if I want to eat fish then I will learn how to fish.

It is certainly possible that going over material in some way will improve memory, but not simply through the power of repetition – if this were the case I would remember the hymns I sang at school, or my railcard ID. Some forms of repetition – especially elaboration - will almost certainly improve learning but only because they build the Affective Context of the information, not simply because one is ‘going over’ the information. Good teachers know that getting students to debate how they feel about topics is a far more effective approach than simply getting them to write it down. Most students learn most in the run-up to their exams – when they are really anxious – but effective teachers can get students to care about the subject-matter way in advance. Good learning is inspired by great teachers – and great teachers aren’t using rote learning.

There are practical reasons for making this point; with most of our training we don’t have the opportunity to force employees to rehearse it at regular intervals. I’m not sure I’d want to – imagine having to repeat the same Safety Training every month. What we try to do is make the information stick first time round, and this can be done in a whole host of ways, all of which have affective context in common (such as making it relevant, using memorable examples, delivering it in context, encouraging people to think about it and delivering it passionately and authentically). When we conducted our own research we found that the vast majority of the things BBC staff remembered were one-off experiences. One colleague will never forget the teacher who told him ‘you will never succeed at anything’. Look back at your own memories, if you don’t believe me. For my part I confess that I can no longer recall my times’ tables – despite rehearsing them thousands of times. I do recall quite vividly the time when we kept a pet crow in a school desk.

In conclusion, there is a familiar pattern at work here: if you focus only on what happens to information, instead of what learners are actually learning, then you will never understand the process. Learning is no more the transfer of information than cookery is the transfer of calories.

This parrot is definitely dead.