Connectome harmonic decomposition tracks the presence of disconnected consciousness during ketamine-induced unresponsiveness.
British journal of anaesthesia April 1, 2025 Milan Van Maldegem, Jakub Vohryzek, Selen Atasoy et al. 3 citations
Ketamine, at anesthetic doses, produces a state where people are unresponsive yet often report vivid inner experiences, separating conscious awareness from behavioral responsiveness. Using connectome harmonic decomposition on fMRI data, researchers found that brain signals during ketamine-induced unresponsiveness show increased fine-grained spatial patterns, indicating higher neural granularity. This harmonic signature aligned with those of LSD-induced and ketamine-induced psychedelic states, but misaligned with signatures from unconscious individuals due to propofol sedation or brain injury. The method can track changes in conscious awareness even when behavior is absent, offering a tool for consciousness and anesthesia research.