Antonio Damasio’s Self Comes to Mind is a modern retake on the biological basis, or neural correlates, of consciousness. The foundational, and in my estimation most important, idea in this new work is the functional role of homeostasis and its emergent role in creating the biological value of life regulation—which he says is the most fundamental value, with all higher-level values being traced, directly or indirectly, back to it in some way. As the organism grows in complexity to the point of possessing a brain, they are able to construct maps of the body in order to monitor homeostatic ranges, among other things. Eventually, these maps come to be able to correspond to events and ideas rather than simply the organism itself (his concept of convergence-divergence zones is crucial here, and I suspect it will come to be foundational in studies of further NCCs). As the title suggests, Damasio suggests that the turning point in the evolution from mere mind to conscious mind comes when a coherent protagonist, or self process, is added to the mix. This centering self process allows the organism to better adapt to its environment, plan ahead, and eventually, reflect on itself in more abstract terms.
Damasio takes one chapter aside to speak specifically to the issue of Qualia, and provides some tenable arguments for relating his proposed biological mechanisms to the phenomenal experiences discussed elsewhere, though the arguments are in no way complete. This may be of interest to those with a philosophical bent.
tl;dr, and in summary: this is a bold book, worth reading for anyone interested in learning more about the biological basis of consciousness. It is complex in its ideas, but simple enough to be understood at a basic level with even the most basic of understandings of brain science (the appendix provides a sufficient background in brain architecture for the purposes of the book).