The head is inverted which means that if it is perceived as a proper head, the head follows you as you move. Actually it moves at twice the rate of your movement in relation to it.
A small version of this model was in Constructor Quarterly and paper cut-outs have been available since the late 1990s.
If you want to make this yourself, I would recommend red or blue plastic plates as they do not reflect so much. If you look carefully the teeth are reflected in the snout which is a paradox and can spoil the illusion.