We propose that consciousness requires four neural loops to synchronize within 50-150ms windows: (1) an ACC-mediodorsal thalamic loop detecting prediction errors; (2) a VTA-cortical dopaminergic loop computing prediction error magnitude; (3) a central lateral thalamocortical loop maintaining global integration; and (4) Layer 5 pyramidal recurrent loops enabling local cortical processing. This is a claim about necessary conditions, not neural correlates: single-loop disruption produces characteristic altered states rather than eliminating consciousness, while simultaneous multi-loop disruption eliminates it reliably. No documented clinical case exists of bilateral destruction of any single loop component alongside preserved normal consciousness, providing a zero-case falsification criterion. The framework explains why anesthesia requires multiple pharmacological mechanisms, why patient H.M. remained conscious despite bilateral hippocampal ablation, and why Alzheimer's disease behavioral symptoms should precede cognitive decline in a predictable loop-failure sequence. Nine discriminating predictions are specified, including that standard cognitive screening will miss isolated Loop 1 failure, that gamma oscillation decline will precede cognitive symptom onset, and that anti-amyloid monotherapies will show minimal cognitive benefit despite plaque clearance. The framework subsumes the empirical commitments of Global Neuronal Workspace theory and Integrated Information Theory while generating predictions neither theory produces.
Arthur Stewart (Wed,) studied this question.