This picture is self referential is refers back to itself

so what does it mean for us humans to be self referential?

A paradoxes involving  negation in an essential way, e.g. sentences saying of themselves that they are not true or knowable. 'I am feeling really depressed...(upon consideration) '...no, not really ...I am  fine.'

We could term this with it role of negation '...no, not really ...I am  fine.'

So there are such paradoxes of self-reference