Uncovering the role of neuromodulation in memory linking

We are excited to share our latest study in collaboration with the lab of Alcino Silva at UCLA.  This work, published in NEURON, explores the role of neuromodulation by dopamine to the linking of memories. Memories are often linked, meaning that recall of one memory triggers the recall of another. In this study, UCLA scientists A. Chowdhury, A. Luchetti et al. show that the Locus Coeruleus plays a gating role in memory linking by modulating the size of the overlapping population of neurons that express both memories in the dorsal CA1 region of the hippocampus. This is the first discovery of a neuromodulatory mechanism that affects memory linking specifically, without affecting individual memories.

In order to uncover the sub-cellular mechanism underlying this linking, George Kastellakis and Alexandra Tzilivaki in our lab used computational models. They showed that by modulating the excitability of neurons in CA1, dopamine can regulate the overlapping population of neurons without affecting the populations expressing each memory separately. Our modeling thus suggests that dopamine-related mechanisms that affect neuronal excitability in CA1 can induce or prevent memory linking by modulating neuronal adaptation currents (such as the AHP).

This work is important as it provides the first experimental evidence of a neuromodulatory modulation of memory linking and pinpoints the subcellular mechanism via which this modulation is achieved.

You can read our full study in NEURON.