Screwing one's face in effort

Recently I was having trouble opening a chocolate bar wrapper and realised I was screwing up my face even more tightly as my efforts increased. Totally unremarkable behaviour and I don’t think I’ve seen anyone who doesn’t do it, but why? I can see no connection between facial muscles and those of my hands and arms, and, as I was doing it alone, it wasn’t communicating my frustration. I can imagine no physical, psychological or evolutionary reason for such a pointless reaction. Any ideas anyone?

Not an answer but I too have long pondered on this while watching musicians doing physiognomical contortions, as though creating a few riffs is torture.

Back in his stand-up days, Jerry Seinfeld used to talk about the “back-up face” we all put on when looking over our shoulder while reversing a car. He then demonstrated what it would look like if we wore that face all the time while driving. Hi-sterical.

Joe Cocker!

Perhaps the motor homunculus gives a clue.

The “face” and “hand” are very close to each other, so action in one can spill over to the other?

Strength coach Pavel Tsatsoline discusses how tensing more/every muscle in your body will allow for greater muscle recruitment and allow you to lift greater loads.

I’ve noticed this will finishing a long set of pushups and other exercises. Whether it’s overcompensation for improper form or not (i.e. you can’t get tension specifically in the proper muscles, so you tighten them all and hope to hit the ones you need), I couldn’t say.

That’s what I was thinking. It sems to me you tense all your muscles to some extent.

On the other hand, if it has to do with the face it may have to do with what most things have to do with your face. Commuincation. Your sending out a signal that you’re doing something streneous. So your fellow primates know…err…not to ask you to pick lice out of there hair right then. Or the like.

I would be surprised if it didn’t have some sort of value as a communicative feature. And certainly it wouldn’t always be useful for that purpose - as when you’re alone - but since it’s not a consciously-mediated process, there’s no reason it couldn’t happen anyway.