Player piano

Just a minute ago I noticed that I had been “playing piano” with my hands on my hips, to a song I had listened to a few hours ago. I was quite unconscious of it and I did not know how long I had been doing it for.
It’s quite scary, in fact – I have been “playing piano” with my hands since over 10 years ago, and it’s become so common that it’s become almost completely subconscious. What’s more, in the same time, I’ve lost the actual ability to play piano. From a psychological perspective, I’d say it’s quite interesting that such an action can become somewhat of a nervous twitch.