I just finished an interview for the Wall Street Journal here is one of the topics I discussed Facial Feedback Loop and reason to smile!

Here is a research quote of the facial feedback loop that explains why I do outside in coaching (change the smile to change how you feel) and inside out coaching (change how you feel to effect the clients smile. )
The facial feedback hypothesis states that individuals can initiate emotions through their facial expression (McIntosh, 1996). If individuals make a specific facial expression, it will illicit the emotion. The facial feedback hypotheses proposes that expression amplify our emotions by activating muscles associated with specific states and the muscles signal the body to respond as through we were experiencing those states. Thus when we simulate the facial expressions normally associated with happiness, we may fell happier. Similarly, the behavior feedback hypotheses assumes that if we move body as we would when experiencing some emotion such as smiling when we are happy, we are likely to feel that emotion to some degree.
Research Strack, Martin, and Stepper (1988) provided a relevant study in support for the facial feedback hypothesis. These researchers utilized the facial simulation procedure in which participants were posed into a certain facial pose. This technique has often been associated in testing the facial feedback hypothesis. Participants were asked to read a set of cartoons and respond by rating how humorous the cartoons were. The condition of the facial-pose simulation was used utilizing a pencil placed between the teeth of some participants. The three conditions of the pencil included between the teeth, lips, or use of the non-dominant hand (Strack, Martin, & Stepper, 1988). Results and ratings concluded that those who held the pencil between their teeth, producing a smile rated that the cartoons were more humorous than those that inhibited the smile.
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