The posterior dominant rhythm: an electroencephalographic surrogate for cognitive recovery after general anaesthesia

The posterior dominant rhythm (PDR) was the first oscillatory pattern noted in the EEG. † A.K. Labonte and M.M. Kafashan contributed equally to this work. Evoked by wakeful eyelid closure, these oscillations dissipate over seconds during loss of arousal. The peak frequency of the PDR maintains stability over years, suggesting utility as a state biomarker in the surveillance of acute cognitive impairments. This EEG signature has not been systematically investigated for tracking cognitive dysfunction after anaesthetic ablation of consciousness.