Attention schema theory

The attention schema theory (AST) of consciousness is a neuroscientific and evolutionary theory of consciousness (or subjective awareness) developed by neuroscientist Michael Graziano at Princeton University. It proposes that brains construct subjective awareness as a schematic model of the process of attention. The theory is a materialist theory of consciousness. It shares similarities with the illusionist ideas of philosophers like Daniel Dennett, Patricia Churchland, and Keith Frankish.

Graziano proposed that an attention schema is like the body schema. Just as the brain constructs a simplified model of the body to monitor and control its movement, it also constructs a model of attention to help monitor and control its own attention. The information in that model, portraying an incomplete and simplified version of attention, leads the brain to conclude that it has a non-physical essence of awareness. Thus subjective awareness is the brain's efficient but imperfect model of its own attention. This approach intends to explain how awareness and attention are similar in many respects, yet are sometimes dissociated; how the brain can be aware of internal and external events, and provides testable predictions.

In the theory, an attention schema necessarily evolved due to its fundamental adaptive uses in perception, cognition, and social interaction.

The AST describes how an information-processing machine can claim to have a conscious, subjective experience, while having no means to discern the difference between its claim and reality.

In the theory, the brain is an information processor captive to the information constructed within it. In this approach, the challenge of explaining consciousness is not, "How does the brain produce an ineffable internal experience," but rather, "How does the brain construct a quirky self description, and what is the useful cognitive role of that self model?"

In other words, because we claim to be conscious, some mechanism in the brain must therefore have computed the requisite information about consciousness to enable the system to output that claim. AST proposes that this is an adaptive function: it serves as an internal model of one of the brain's most important features: attention.

A crucial aspect of the theory is model-based knowledge. The brain constructs rich internal models that lie beneath the level of higher cognition or of language. Cognition has partial access to those internal models, and the content of those models are reported as literal reality.

The AST can be summarized in three broad points: