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

Sleep Stages Diagram

(György Buzsáki -  Rhythms of the Brain, 188)



Sleep is a dampened oscillation with approximately 90-minute periods.

Top: Hypnogram of a night's sleep in a young adult human. Note periodic ascending and de­scending phases.

Bottom: Representative scalp-recorded EEG segments from each sleep stage.

Return to — Sleep and Dreaming

A delta frequency rhythm (1-4 Hz) can be generated in single cells by the interplay of two intrinsic currents of thalamocortical neurons. (Sejnowski; Thalamocortical Oscillations, 977)

Spindle oscillations consists of 7-14 Hz waxing and waning field potentials, grouped in sequences that last for 1-3 seconds and recur every 3-10 seconds. (Sejnowski; Thalamocortical Oscillations, 978)