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Hippocampal ripples are prominent synchronization events generated by hippocampal neuronal assemblies. To date, ripples have been primarily associated with navigational memory in rodents and short-term episodic recollections in humans. Here, we uncover different profiles of ripple activity in the human hippocampus during the retrieval of recent and remote autobiographical events and semantic facts. We found that the ripple rate increased significantly before reported recall compared to control conditions. Patterns of ripple activity across multiple hippocampal sites demonstrated remarkable specificity for memory type. Intriguingly, these ripple patterns revealed a semantization dimension, in which patterns associated with autobiographical contents become similar to those of semantic memory as a function of memory age. Finally, widely distributed sites across the neocortex exhibited ripple-coupled activations during recollection, with the strongest activation found within the default mode network. Our results thus reveal a key role for hippocampal ripples in orchestrating hippocampal-cortical communication across large-scale networks involved in conscious recollection. • Simultaneous iEEG recordings of cortex and hippocampal ripples linked to cognition • Ripples selectively activate during autobiographic and semantic memory recall • Multisite ripple activity patterns reflect memory semantization processes • Ripples coordinate a DMN-centered cortical-hippocampal interplay during recall Norman et al. report that synchronous hippocampal bursts (ripples) selectively emerge when patients recall past autobiographical events. Those ripples form spatial patterns that become increasingly similar to semantic-memory patterns, the more remote the memory. The results demonstrate the pivotal role of ripples in coordinating recollections in the human brain. [ABSTRACT FROM AUTHOR]