Associative memory, crucial for learning relations between stimuli, involves the medial temporal lobe (MTL). Using single-neuron recordings from epilepsy patients performing an associative object-location memory task, researchers identified object-specific and place-specific neurons. During encoding and retrieval, these neurons activated together during hippocampal ripples, a phenomenon that strengthened with learning. The ripple-locked timing shifted between encoding and retrieval, suggesting MTL neuron-ripple interaction flexibility.

Lukas Kunz, Bernhard P. Staresina, Peter C. Reinacher, Armin Brandt, Tim A. Guth, Andreas Schulze-Bonhage, Joshua Jacobs