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

Consciousness as ‘Remembered Present’

Certain aspects of memory are essential for consciousness. Gerald Edelman’s theory of consciousness, which I think is on the right track for eventually providing valid central tenants of a refined theory, states in somewhat arcane words that “primary consciousness results from the interaction in real time between memories of past value-category correlations and present world input as it is categorized by global mappings.” (Edelman; Remembered Present, 155)

A dynamic memory system operates within the brain's mechanisms leading to perceptual categorization. Global mappings, concept formation, and. dynamic short-term memory all call upon interactions of the three major motifs of global neural systems. These major motifs are the (1) thalamocortical maps, the (2) subcortical organs concerned with temporal succession (the hippocampus, basal ganglia, and cerebellum), and the (3) diffuse ascending value systems. To reflect these interactions, Edelman has called the central memory system a value-category memory system. (Edelman; Wider, 53)

These dynamic reentrant interactions in the thalamocortical system must be thought of as successive in time—new perceptual categorizations are reentrantly connected to memory systems before they themselves become part of an altered memory system. This boot­strapping between memory and perception is assumed to be stabilized within time periods ranging from hundreds of milliseconds to seconds. Edelman has called this period "the remembered present" to point up the dynamic interaction between memory and ongoing perception that gives rise to consciousness. (Edelman; Wider, 55)