The (Learning) Element Of Surpr!se

From sparks and whizzbangs in the chemistry lab to the class novel’s unexpected plot twist, confounding students’ expectations taps into the system by which we educate ourselves about life, by activating the brain reward system. So what’s not to like about ‘prediction error’? Chris Parr explores the latest concept looking to gain a foothold in how children are taught

You’re sure it’s a dog. And you’re sure it is a big dog. The street is residential, it’s the middle of the afternoon, and no one is about. The bark from behind you, just beyond your left shoulder, is loud – thunderous, even. It can only be a monstrous, drooling guard dog.

You turn around slowly, heart racing, sweat beading, and…

A tiny black pug, no bigger than your hand, is backing slowly away across a lawn three yards away, barking up a storm but retreating and shaking as it goes.

You laugh, and carry on, not realising that you just learned something. What just happened, you see, was a prediction error.

“The immediate effect of this prediction error is to update our belief from thinking there is a big dog to there being a tiny dog,” explains Peter Kok, a senior research fellow at the Wellcome Centre for Human Neuroimaging at University College London (UCL). “The more long-term effect is that we update our model of the world: loud barks don’t always come from big dogs.”

In neuroscience, a so-called “prediction error” occurs when an expected event fails to materialise. Such incidents cause a range of metacognitive functions to leap into action that force us to re-examine our initial flawed expectations and ask ourselves what we can learn from our errors.

Floris de Lange, a professor at the Radboud University in the Netherlands, reveals that prediction errors can arise from a number of different brain stimuli. They can be sensory – for example, a visual surprise such as a sudden flash; or they can even be semantic. He gives an example of the sentence “the soup was too hot to cry” – the last word elicits surprise because our brains had predicted a different end.