Consciousness

Until recently, most neuroscientists did not regard consciousness as a suit able topic for scientific investigation. This reluctance was based on certa in philosophical mistakes, primarily the mistake of supposing that the subj ectivity of consciousness made it beyond the reach of an objective science. Once we see that consciousness is a biological phenomenon like any other, then it can be investigated neurobiologically. Consciousness is entirely ca used by neurobiological processes and is realized in brain structures. The essential trait of consciousness that we need to explain is unified qualita tive subjectivity. Consciousness thus differs from other biological phenome na in that it has a subjective or first-person ontology, but this subjectiv e ontology does not prevent us from having an epistemically objective scien ce of consciousness. We need to overcome the philosophical tradition that t reats the mental and the physical as two distinct metaphysical realms. Two common approaches to consciousness are those that adopt the building block model, according to which any conscious field is made of its various parts, and the unified field model, according to which we should try to explain t he unified character of subjective states of consciousness. These two appro aches are discussed and reasons are given for preferring the unified field theory to the building block model. Some relevant research on consciousness involves the subjects of blindsight, the split-brain experiments, binocula r rivalry, and gestalt switching.