A rapid oscillation in the frequency range of 20 to 45 Hertz occurs exclusively during waking hours and REM sleep, the phase of sleep with rapid eye movements and intensive dreams, and is entirely absent in non-REM sleep, when consciousness is strongly reduced. Because recording deep brain structures is notoriously difficult using standard surface EEGs, researchers partnered with epilepsy patients undergoing deep brain stimulation therapy by utilizing surgical electrodes implanted directly into the central thalamus, gaining a rare, pristine window to record direct local field potentials. Lead author Dr. Aditya Chowdhury explains that the central thalamus "could actively influence our states of consciousness." The finding isolates a measurable neural rhythm that vanishes when consciousness vanishes, making the mind slightly less mysterious than it was three months ago.
The thalamus hums at 28 hertz when you are you, and goes silent when you are not.