Tuesday, 15 December 2015

The Science of Learning: Five Classic Studies By Tom Stafford

Two chess masters playing chess
A few classic studies help to define the way we think about the science of learning. A classic study isn’t classic just because it uncovered a new fact, but because it neatly demonstrates a profound truth about how we learn – often at the same time showing up our unjustified assumptions about how our minds work.
A classic study defines where research will go next – whether to confirm, disprove or qualify the original finding – and helps us to re-organise our learning to be more effective.
I’m a psychologist, so you won’t be surprised that my choice of classic studies concern the mental processes rather than the social processes involved in learning. Other people might pick a different five studies, but these are mine.

1. Bartlett’s ‘War of the Ghosts’

Frederick Bartlett was a Cambridge psychologist who used a native American folk story called War of the Ghosts to show something fundamental about our memories. The story, and the research study he used it in, are related in his 1932 book Remembering.
The War of the Ghosts is a tale of two young men on a hunting expedition that goes wrong, with one of them becoming involved in a raid on another village in the company of some ghosts. The tale has some familiar elements (the men are hunting seals, they go in a canoe, at one point they hide behind a log, that sort of thing), but it also has some aspects which are, frankly, a bit unusual in western culture: ghosts, a mortal wound that doesn’t hurt, and one of the men dying after “something black” comes out of his mouth.
Bartlett had people read the story and then he tested their recall over intervals varying between 15 minutes and 10 years later. He found, of course, that the longer the delay before testing, the less accurate people were. But the most important result concerned the nature of people’s inaccuracies. Bartlett saw how the memory errors people made tended to focus around the unfamiliar elements. People’s recall was better for things they had a good model of (such as the hunting expedition), but bad for things that they didn’t have a model for (such as the ghosts or the strange wound one of the men receives). These elements got dropped, or distorted in their memories, so as to fit with reasonable expectations. The canoes became boats, for example, or the mortal wound was immediately recognised as fatal.
Bartlett’s studies showed that memory is a constructive process, not something like a video recorder, but a web of associations from which accurate memories – and plausible false memories – are rebuilt as they are needed.
The moral for learning is that you can’t just slot new memories in like writing files to a computer disk. You need to integrate them into what you already know, making connections between old and new information if you’re going to successfully recall them.
BF Skinner is famous as the father of behaviourism, the school of psychology known for training behaviours in pigeons and rats. To this day, the rat cage with a lever and a food pellet tray is called a Skinner box. His great achievement was to show how schedules of reinforcement, such as the delivery of food pellets to hungry rats, could condition behaviour.
One of Skinner’s key claims was that with the right practice conditions – meaning that correct behaviour is appropriately rewarded – any task can be learned using simple associations. This means anything that can form simple associations, even a pigeon, can learn many complex tasks.
The team that, in 1995, taught pigeons to discriminate between Picasso and Monet paintings were intellectual descendants of Skinner. Like him, they believed that we underestimate the power of practice and reward in shaping behaviour. After just a few weeks’ training, their pigeons could not only tell a Picasso from a Monet – indicated by pecks on a designated button – but could generalise their learning to discriminate cubist from impressionist works in general.
For a behaviourist, the moral is that even complex learning is supported by fundamental principles of association, practice and reward. It also shows that you can train a pigeon to tell a Renoir from a Matisse, but that doesn’t mean it knows a lot about art.

3. Dissociable memory systems

We say “it’s like riding a bike” precisely because this kind of memory seems different from the kinds of things we easily forget, like names. What is now indisputable is that different memories are supported by different anatomical areas of the brain.
Pioneering work led by Larry Squire showed that amnesic patients who had trouble remembering episodes of their lives had no trouble performing a new skill they had learned. Brain imaging has confirmed the basic division of labour between so-called declarative memory, aka explicit memory (facts and events), and procedural memory, aka implicit memory (habits and skills).
The neuroscience allows us to understand the frustrating fact that you have the insight into what you are learning without yet having acquired the skill, or you can have the skill without the insight. In any complex task, you’ll need both. Maybe the next hundred years of the neuroscience of memory will tell us how to coordinate them.

4. Inside the mind of the Chess Masters

Lab studies of learning tend to ask people to learn something new. Another approach is to take existing experts and look at how they do what they do so well.
Adriaan de Groot was a Dutch chess master as well as a psychologist. His studies of how chess experts think began the modern study of expertise. One of his findings was that chess masters have an amazing memory for patterns on the chess board – able to recall the positions of all the pieces after only a brief glance. Follow-up work showed that they only have this ability if the patterns conform to possible positions in a legal game of chess. When pieces are positioned on the board randomly, however, chess grandmasters have as poor memories as anyone else.
The result confirms the idea that knowledge is a web of associations – when you have a large existing store of knowledge it is easy to spot patterns and so remember the positions of all the pieces. This also helps us to recognise what is wrong with the idea of brain training. Our skills and memories aren’t like muscles. You don’t get better at remembering faces by practicing remembering digits, and even if you train to become a world-class chess master you won’t necessarily develop a better memory in other areas of your life.

5. Ericsson’s 10,000 hours of deliberate practice
Anders Ericsson is famous for claiming that all world-class performers have in common is that they have all invested at least 10,000 in deliberate practice. Deliberate practice means effortful, structured practice focusing on reducing your failings and errors, constantly pushing yourself to improve.
Deliberate practice isn’t much fun, but whether the domain is figure skating or chess, the thing that distinguished the best of the best from the runners-up was the way they had arranged their lives to prioritise practice. As well as underlining the golden rule of learning – you have to practice – Ericsson’s idea also has a strong egalitarian air. Don’t worry about innate talent, just find a way to put the hours in.
No study is perfect. Even without flaws, there are caveats to how they should be applied, and distortions in how they have been interpreted, but for better or worse these studies define how psychologists think about learning.

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