Alzheimer’s Study Finds Memory “Replay” Persists but Loses Structure

Overview

• In an amyloid mouse model, replay events occurred as often as in healthy mice, yet the ordered place‑cell sequences were disorganized.
• Place‑cell representations became less stable over time, especially after rest periods when replay would normally reinforce spatial maps.
• Mice with amyloid pathology performed worse on a radial arm maze, repeatedly revisiting arms they had already explored.
• Researchers recorded activity from roughly 100 hippocampal place cells simultaneously using high‑density electrode arrays during behavior and rest.
• The team is investigating whether acetylcholine modulation can restore replay structure, with potential to inform early diagnostic tests and targeted treatments; the peer‑reviewed report appears in Current Biology.