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bioRxiv · 10.1101/2024.05.20.594930

Projections from thalamic nucleus reuniens to medial septum enable extinction of remote fear memory

Tomaszewski, K. F.·Ziolkowska, M.·Lukasiewicz, K.·Caly, A.·Sotoudeh, N.·Puchalska, M.·Salamian, A.·Radwanska, K.
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Abstract

Aversive experiences lead to the formation of long-lasting memories. Despite the need to better understand how enduring fear memories can be attenuated, the underlying brain circuits remain largely unknown. In this study, employing a combination of genetic manipulations, neuronal circuit mapping, and chemogenetics in mice, we identify a new projection from the thalamic nucleus reuniens (RE) to the medial septum (MS), and show that this circuit is involved in the extinction of remote (30-day old), but not recent (1-day old), fear memories. These findings provide the first functional description of the RE[->]MS circuit and highlight the significance of the thalamo-septal regions in memory organization as a function of memory age, a phenomenon known as systems consolidation.

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Tomaszewski, K. F., Ziolkowska, M., Lukasiewicz, K., Caly, A., Sotoudeh, N., Puchalska, M., Salamian, A., Radwanska, K.. 2024-05-20. Projections from thalamic nucleus reuniens to medial septum enable extinction of remote fear memory. https://doi.org/10.1101/2024.05.20.594930

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