Ripple highways bind distant brain regions to sustain working memory

Intracranial recordings from epilepsy patients performing a Sternberg working memory task show that high-frequency ripple oscillations co-occur across distant brain regions (up to ~220 mm) and boost cross-regional neuronal co-firing by ~30% during encoding, maintenance, and retrieval. Co-ripples scale with memory load and, during retrieval, reinstate stimulus-specific long-range co-firing patterns observed at encoding, indicating ripple-mediated coordination supports distributed memory representations across hippocampus, amygdala, vmPFC, ACC and preSMA.