One of the most important body language skill you can have is knowing how to detect a sincere smile and in producing one of your own – often and at will. Most people can’t do either very well.
What is the key part of the face to look at when differentiating a true, felt smile (Duchenne Smile) versus a polite aka fake smile?
What parts of the teeth, if any, are hidden during a sincere smile? When you want to make a true smile - what part of your face should you “lead with”? What changes occur in the brain when you make a Duchenne Smile?