Re: is it true we need 43 muscles to frown and only 17 to smile?

Cat:

Pubmed.gv didn't have anything when I did a search on "smile" and "frown" so I checked that snopes.com.
http://www.snopes.com/science/smile.asp indicates that the count is fairly nonsensical.

There's a couple of considerations that probably make an exact count impractical:
(1) does the smile or frown reach the eyes? If the eyes crinkle, then that's more facial muscles involved.

(2) how intense is the expression? I would think a broad, open grin would require more muscles -- or at least more work from the same muscles -- than a small, close-mouthed smile. Similarly, a strong expression of shock or dismay would probably require more facial muscle activity than a show of mild disappointment.

And the whole "frowning is less work because it requires fewer muscles" argument goes out the window if you consider that a few large muscles do more work than many small muscles, and muscles can be activated at different levels of force.

For the rccord -- I usually think I'm smiling, but in college people used to to come up to me and try to cheer me up just based on my face!

Regards,

Mitch