Danielle Turner

Surprise, Surprise !

If you want to be remembered - surprise someone!

Your brain will definitely notice !

In the dark, noisy, enclosed environment of a brain scanner I ask

healthy volunteers to imagine they are experts on food intolerance

- trying to help a patient who suffers from a range of weird and

wonderful food allergies. Learning which foods do what, they lie

on their backs staring at a stream of food pictures. Some foods

cause their imaginary patient to react with a nasty allergy. Some

foods seem pretty harmless, and some even prevent allergies. Then

suddenly, just when they are settling in, feeling confident they

can predict which foods do what, we surprise them. We don't jump

into the scanner and shout "boo", but we may as well.

At the moment when they discover an unexpected reaction in their

imaginary patient an area in the brain, the dorsolateral prefrontal

cortex, lights up.

Researchers at Cambridge University coined a term "super-learning".

They showed that if you are "super-surprised" you will

super-learn. That is, the more unexpected something is the more

you will learn about it.

Sounds like the latest fad for stressed-out students - make everything

totally unexpected and get an A-grade! But it seems to work. Imagine

you were taking part in my experiment. You have learnt that a particular

food always helps prevent allergies no matter what it is eaten with.

Then, bizarrely, you discover a food so powerful that it causes

an allergic reaction in your patient even when eaten with the "allergy

preventing food". It is totally unexpected and you remember

much more about the extra-powerful food. Your brain remembers the

unexpected.

When we scanned people performing this task we discovered the amazing

specificity of the brain's response. The dorsolateral prefrontal

cortex, an area in the important frontal area of the brain, lit

up every time something surprising happened. And it lit up the greatest

amount in the volunteers that learnt the most. The learning occurs

specifically because the result was unexpected.

So why did people learn so easily about the unpredictable allergy-causing

food? Perhaps because human beings are highly tuned-in to detect

the unexpected. Finding out about our environment is essential for

our survival. From the moment we are born we are on the lookout,

discovering new things around us and modifying our behaviour appropriately.

We have the inborn capacity to revise and change our ideas in the

face of surprises. Many argue that our ability to change and adapt

to prevailing conditions is the fundamental cause behind our development.

It is interesting that we showed the area most sensitive to surprise

to be in the frontal cortex. The frontal lobes of humans are much

larger than in the animals we consider our nearest relatives; many

scientists claim this area of the brain provides us with the ability

for complex thought. We believe it is even more fundamental than

that. This could be the area of the brain that drives all our behaviour,

helping us to reconcile the unexpected in our environment with what

we know from the past. This helps us to make predictions about events

in our surroundings, to learn to control them and to create the

society we live in today.

- November 2005

About the Author

Danielle Turner is a member of the Dept. of Psychiatry at Cambridge University