Amy Cuddy is a social psychologist that teaches at Harvard Business School. She is known for her research on stereotyping, discrimination, and nonverbal behavior.
Cuddy asks the question, do our nonverbals (body language) govern how we think about ourselves? Her answer is simply, yes. If we are able to mimic the body language of those who are more powerful or more confident, for example, then we will exude more confidence and feel more powerful. If we imitate the body language of those who are happy, i.e. smiling, we tend to feel happier. If we are typically shy or hesitant about speaking in public, we can impersonate a more confident speaker, i.e., act the part until we become the part.
How we feel governs our actions and outward behavior, but our behavior and body language can also condition how we feel. It is a two way street.
Below is a presentation by Amy Cuddy on whether your body language can shape who you are. The video is long, but I would recommend watching the whole thing. However, if you would just like the a shortened version, skip ahead to 6:25 and watch it for a few minutes.
After watching this video, I attempted this in my European Economic History class at UC Berkeley. I sat up straight, made myself bigger, and raised my hand high with authority. Before I knew it, I found myself participating and giving insight into the problems we were discussing in class. I am not sure that I became instantaneously self-assured but it got me through all of the uncertainty surrounding what it takes or means to be a confident participant. I started then to do this in my other classes and noticed the same pattern.
I found, much like Cuddy, that if you “fake it” enough, at some point you "make it." It becomes who you are in the classroom. Without thinking about it you begin to sit up taller, take up more space, raise your hand higher, and speak a little louder. All of these things make you more powerful in your surrounding area, and allow you to be more assertive and confident in your day-to-day life.