Hidden Horns 🐏, Silent Signals ⚡, New Memories 🧠

A new Science review reframes the hippocampus beyond the classic trisynaptic loop. Once-overlooked regions like CA2, fasciola cinereum, and indusium griseum — along with enigmatic signals such as small irregular activity (SIA) and dentate spikes (DS) — emerge as crucial for social memory, novelty detection, and arousal states. Far from "junk activity," these dynamics expand our map of hippocampal computation with deep clinical implications.