I don’t have very big eyes, and you’ll almost never ever see me opening them wide, but the amount of emotional expression communicated through my eyes is probably still on par with the amount that’s conveyed through my mouth. Mostly of course, because I don’t use my mouth much at all.
Even when I smile, I smile at people with my eyes. When I’m upset, it’s the eyes that show it. When I’m confused, wondering, thinking, pensive, thoughtful, worried, nervous–it’s my eyes that give it away.
I guess everyone communicates emotions with their eyes a lot, though. The difference with me is that I don’t use my mouth at all, so it really is just my eyes that show it.