Rotating waves during human sleep spindles organize global patterns of activity that repeat precisely through the night.
During sleep, the thalamus generates a characteristic pattern of transient, 11-15 Hz sleep spindle oscillations, which synchronize the cortex through large-scale thalamocortical loops. Spindles have been increasingly demonstrated to be critical for sleep-dependent consolidation of memory, but the specific neural mechanism for this process remains unclear. We show here that cortical spindles are spatiotemporally organized into circular wave-like patterns, organizing neuronal activity over tens of milliseconds, within the timescale for storing memories in large-scale networks across the cortex via spike-time dependent plasticity. These circular patterns repeat over hours of sleep with millisecond temporal precision, allowing reinforcement of the activity patterns through hundreds of reverberations. These results provide a novel mechanistic account for how global sleep oscillations and synaptic plasticity could strengthen networks distributed across the cortex to store coherent and integrated memories.
Computational Neurobiology Laboratory, Salk Institute for Biological Studies, La Jolla, United States. Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, United States. Computational Neurobiology Laboratory, Salk Institute for Biological Studies, La Jolla, United States. Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, United States. Department of Radiology, University of California, San Diego, San Diego, United States. Department of Neurosciences, University of California, San Diego, San Diego, United States. Computational Neurobiology Laboratory, Salk Institute for Biological Studies, La Jolla, United States.