This does not directly address your original statement (which I don't quite agree with, by the way) but you might want to look into affect theory. It's a complex theory, but some of its core involves the notion that immediate, involuntary reactions to events are biological in nature and last only for a very brief time; these are known as affects, there are (according to affect theory gurus) nine of them, and we are often not quite aware of them, in their milder forms. Sometimes we get a stronger affect which can lead to a conscious feeling, which in turn may lead to a displayed emotion. That's an extremely condensed explanation, naturally.

I don't buy the theory wholesale (I buy very few theories wholesale, there are always too many factors to consider) but it is interesting and rather illuminating stuff. In particular it makes sense that there is a strong biological component there.