I think I'll stick to the terminology from the Pete Walker's book. I think participating in improv theater helps enormously to shrink the inner critic.

According to the book, the inner critic is the internal voice (or feeling in my case), saying how stupid, useless and incompetent I am. And until this voice is lowered all other therapeutic methods are very inefficient. The inner critic sabotages every healing action, together with the outer critic which is the voice that criticises everyone and everything around, including the therapy.

Now back to the inner critic, which is the biggest problem in my case: I think that participating in improv theater teaches me to ignore the inner critic's voice. I think that the best improv members are the ones who are best in ignoring this voice. I spoke with some of them and they said that even the best have this inner critic voice all the time while they perform, just no one knows about it, except them. It's not possible to get rid of it, the trick is to act spontaneously regardless of it. And it also amazes me that indeed, when I acted despite that voice the other people seemed to have been totally unaware of it! I presume that the more time I spend acting despite that voice the smaller it must get.