Scientific Understanding of Consciousness
Consciousness as an Emergent Property of Thalamocortical Activity

Dynamic Core Diagram by Edelman

(Edelman, Wider Than the Sky , 70)

The Dynamic Core

The thalamocortical system, which gives rise to the dynamic core, is represented by a fine meshwork of cortical and thalamic areas and reentrant connections. The core is composed of a functional cluster that speaks mainly to itself through an enormous complex of signals that fluctuate in time across the reentrant meshwork. Responses triggered by the reentrant dynamic core can also stimulate nonconscious responses. These travel along parallel, polysynaptic, one-directional pathwaysthat leave the cortex, reach the various components of the basal ganglia and certain thalamic nuclei, and finally return to the cortex. In this way, responses subserving consciousness can connect to activity patterns in nonconscious areas, served mainly but not exclusively by the basal ganglia. (The ganglia and the thalamus have been displaced and enlarged for clarity.)

Areas of the cortex not in the core at some particular time can also interact with such nonconscious activity patterns. At some subsequent time hundreds of milliseconds later however, neuronal groups from these areas can participate in the core.

I have a more schematic thalamocortical diagram.