Communication issue

I don't know how, but I have clearly managed most of my life without muscles between the shoulder blades. Interesting. Now trying to find them is incredibly difficult. How do you exercise muscles that don't exist? The brain has no one to send the signals to. It's like facing the wild sea, crying to the horizon and hope that someone hears you.

My whole body is shaking after today's yoga class. So I have obviously exercised some muscles. Just not the ones between my shoulder blades. Especially not around my right shoulder blade.