This week I attended the shooting of Die Große Show der Naturwunder in Freiburg. There will be a segment on felt and false smiles. This is a very interesting topic of course. Going back to Duchenne, we know that crows feet wrinkles can make the difference between a smile that looks "real" and one that does not. As it turns out, there is considerable empirical evidence that smiles showing this feature - it involves the contraction of the muscle orbicularis oculi are more likely to occur when somebody is indeed happy or amused, but that does not mean that all smiles with the wrinkles are genuine, and all smiles without are fake - just that the probability is higher. Other features that have been suggested to differ between posed and felt smiles relate to the timing - how long does it take for the smile to hit its maximum, or apex, how long does it stay there, how fast for it to disappear. It has also been suggested that felt smiles are more symmetrical than post ones. However, for this feature the empirical evidence is weakest. Some critical evidence regarding the differences of "felt" and "false" smiles has recently been presented by my colleagues Eva Krumhuber and Tony Manstead.
The show will be transmitted on July 1, 2010 at 20:15 in ARD