I can't find my abs!

My abs have gone missing.

Well, not really, they're still there, but I can't find them. I'm back at physio to get my back stronger and it has become apparent that I can't find my abs. Sometimes I find them, usually by accident, sometimes accidentally on purpose, but never just because I want to find them. Grrr...

They actually did an ultrasound on my abs the other day so that I could see them at work, at what do you know, I engage every other muscle, including ones I don't want or need to engage, but I can't find my abs...

Help me find my abs!