Siewert, C. (2016), Consciousness and Intentionality, The Stanford Encyclopedia of Philosophy, Fall 2016 (first version Fall 2002). plato.stanford.edu/archives/fall2016/entries/consciousness-intentionality/
[Abstract]To say you are in a state that is (phenomenally) conscious is to say—on a certain understanding of these terms—that you have an experience, or a state there is something it’s like for you to be in. Feeling pain or dizziness, appearances of color or shape, and episodic thought are some widely accepted examples. Intentionality, on the other hand, has to do with the directedness, aboutness, or reference of mental states—the fact that, for example, you think of or about something. Intentionality includes, and is sometimes seen as equivalent to, what is called “mental representation”. Consciousness and intentionality can seem to pervade much or all of mental life—perhaps they somehow account for what it is to have a mind; at any rate they seem to be important, broad aspects of it. But achieving a general understanding of either is an enormous challenge. Part of this lies in figuring out how they are related. Are they independent? Is one (or each) to be understood in terms of the other? How we address the issues to which these questions give rise can have major implications for our views about mind, knowledge, and value.
Note:
The first time Place (1956) is cited is in the Fall 2016 version.
[Citing Place (1956)]  
Citing Place (1956) in context (citations start with an asterisk *):
Section 5. Varieties of Intentionalism
* One evidently fundamental division in views about the relationship of consciousness and intentionality separates those who think that consciousness—more specifically, the phenomenal character of the sort of experience we actually have—necessarily carries with it some kind of intentionality, and those who do not. We might call the former (as will be seen, quite varied group) “intentionalists” and the latter (following Horgan and Tienson 2002) “separatists”. Intentionalism, so characterized, can cover a wide variety of positions, partly because of potential variety in just how intentionality is conceived. Exactly what contrast is marked by “intentionalism vs. separatism” will depend heavily on one’s conception of intentionality.
Still, operating at first only with a broad and open notion of this contrast, perspectives reasonably regarded as separatist occupied the mainstream of much twentieth century analytic philosophy. According to an important (once predominant) view, consciousness is exhausted by non-intentional “qualia” or “raw feels”. Plausibly, the acceptance of this view owes much to the profound influence of Gilbert Ryle’s Concept of Mind (1949) in the development of analytic philosophy. [...] Also powerfully influential, in the same era and intellectual milieu, was Wittgenstein’s (1953) attack on the idea of understanding as an “inner process”, and his criticism of the notion that there could be a private language. [...] partly through the reception of Ryle and Wittgenstein in U.T. Place’s (1956) and J.J.C Smart’s (1959) influential brain-based materialist view about consciousness, the reduction of consciousness to sensation and sensory imagery became firmly implanted in philosophy of mind, since these writings did so much to set the terms of its debates.