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adjacent areas have been studied most intensively. These areas are shown in Figure 2.7 . (A scan of myown right cerebral hemisphere, by the way.) They are the superior temporal sulcus (STS) and the temporo-parietal junction (TPJ). These areas are probably themselves collections of smaller, specialized subunits that presumably work in a cooperative fashion and interact with larger, brain-wide networks. I will describe the details of the TPJ and the STS in later chapters. Here I merely note in brief that they combine the three key properties predicted by the attention schema theory. First, these areas are recruited during social perception. Second, they track one’s own state of attention. Third, damage to them leads to a devastating clinical disruption of awareness. Each of these three properties was discovered and studied separately, and the collision of the three properties in one region of the brain has caused some controversy. How can such diverse, seemingly unrelated properties be reconciled? The attention schema theory may help to solve the riddle by fitting the many results into a single framework.
    In the present theory, the
content
of consciousness, the stuff
in
the conscious mind, is distributed over a large set of brain areas, areas that encode vision, emotion, language, action plans, and so on. The full set of information that is present in consciousness at any one time has been called the “global workspace.” 25 , 26 In the present theory, the global workspace spans many diverse areas of the brain. But the specific property of awareness, the
essence
of awareness added to the global workspace, is constructed by an expert system in a limited part of the brain, perhaps centered on the TPJ or STS and perhaps involving other brain regions. The computed property of awareness can be bound to the larger whole. As a result, the brain can report that awareness is attached to a color, that awareness is attached to a sound, that awareness is attached to an abstract thought.
    This account of consciousness gives an especially simple explanation for why so much information, the majority of processing in the brain, can never reach consciousness. Much of the information in the brain may not be directly linkable to the attention schema. Only brain areas that are appropriately linkable to the attention schema can participate in consciousness.
    Even information that can in principle be linked to the attention schema might not always be so. For example, not everything that comes in through the eyes and is processed in the visual system reaches reportable awareness. Not all of our actions are planned and executed with our conscious participation. Systems that can, under some circumstances, function in the purview of awareness at other times seem to function with equal complexity and sophistication in the absence of awareness. In the present theory, the explanation is simply that the information computed by these systems is sometimes linked or bound to the attention schema, and sometimes not. The shifting coalitions in the brain determine what information is bound to the attention schema and thus included in consciousness, and what information is not bound to the attention schema and thus operating outside of consciousness.
    This account of consciousness is easily misunderstood. I will take a moment here to point out what I am
not
saying. I am not saying that a central area of the brain lurking inside us is aware of this and that. It is tempting to go the homunculus route—the little-man-in-the-head route—to postulate that some central area of the brain is aware, and that it is aware of information supplied to it by other brain regions. This version, a little man aware of what the rest of the brain is telling him, is entirely nonexplanatory; it is a variant of “the magician does it.”
    Instead, according to the present theory, awareness is a constructed feature. It is a complex chunk of descriptive information,
A
. It can be