In his Treatise on Human Nature, David Hume discusses this very question. No perceptual realist, Hume nevertheless went along with the representational component of representational realism.  Like the other empiricists of his time, Hume believed that the immediate objects of cognition are representations.  It was his view of the relation of these perceptions to sensible objects that distinguished the view of Hume from that of Locke (and from Berkeley's idealism).