This experiment is designed to test whether you can spot the difference between a fake smile and a real one
It has 20 questions and should take you 10 minutes
It is based on research by Professor Paul Ekman, a psychologist at the University of California
We will not pass on your personal details to any other organisation without your permission except for the purposes of processing the data for this experiment
Each video clip will take approximately 15 seconds to load on a 56k modem and you can only play each smile once BBC – Science & Nature – Human Body and Mind – Spot The Fake Smile
Spot The Fake Smile
