Reading smiles

Paula Niedenthal says that there are four kinds of smiles: playful, social, power, and fake.

Then Dr. Niedenthal and her colleagues asked the students to place a pencil between their lips. This simple action engaged muscles that could otherwise produce a smile. Unable to mimic the faces they saw, the students had a much harder time telling which smiles were real and which were fake.

I am skeptical about someone with a name like Dr. Neanderthal, but she seems to have shown that putting a pencil in your mouth inhibits mindreading abilities.