Consciousness: From Neural Systems to Phenomenological Experience
An Integrated Information Theory of Consciousness
Friday, May 27, 2011,
2:00 PM - 2:45 PM
Over the past decades, studies have investigated the neural correlates of consciousness with increasing precision. However, why experience is generated by the cortex and not the cerebellum, why it fades during certain stages of sleep and returns in others, or why some cortical areas endow experience with colors and others with sound, remains unexplained. Moreover, key questions remain unanswered. For example, how much consciousness is there when only a few brain 'islands' remain active? How much is there during sleepwalking or psychomotor seizures? Are newborns conscious, and to what extent? Are animals conscious, how much, and which way? Can a conscious machine be built? To address such questions, researchers need to complement empirical observations with a principled theoretical approach. The information integration theory (IIT) posits that i) the quantity of consciousness corresponds to the amount of information generated by a complex of elements above and beyond its parts, and ii) the quality of experience is specified by the informational relationships within that complex. The IIT not only accounts for several neurobiological observations, it specifies how the quantity of consciousness can be measured as the amount of integrated information (ɸ) generated by a system.