As a counterpoint to the above comment, there are also instinctual behaviours that we don’t even know we’re doing. The proof is in that blind-from-birth people have been seen performing the same sorts of behaviours as sighted people, but they can’t possibly have learned by watching.

Smiling is one such proven example, as are hand movements when talking.

I’m not sure where the head-in-hands of despair falls with regard to this, but given that we see other great apes and monkeys do similar things in similar situations, there might well be an element of instinct to it.