Briton Kolber, MA, LMFTA
Improvisation is defined by the phrase, "Yes, and…" where all participants accept what has been said and add to the action. This creates a positive environment with no wrong answers where all participants support each other in a positive social experience. We set up a social context that sets everyone up to listen and support each other.
Regular improv classes are brilliant, fun, and educational. Therapeutic Improv involves a bit more focus on the interior process and self-growth as an individual and a group. You can still be hilariously inappropriate, just learn more along the way.
You can learn to calm the emotional processing centers of the brain, learn how to make choices rather than react under pressure, feel exhilarated by getting emotions out in the open, and learn how to feel emotionally safe over time and with practice. In improv you practice being right at the point of scariness and then you are supported by people in the same situation.
Improv and Anxiety:
Improv improves and alleviates anxiety: http://www.nwitimes.com/niche/get-healthy/mental-health/improv-improves-and-alleviates-anxiety/article_0069e627-69a8-5c27-a5ca-a80f3821bc5d.html
Paper on Improv and Trust, ~Improvisation and Trust: Mutually Reinforcing?