AI Article Synopsis
- Memories of life episodes are crucial to individual stories, but understanding how episodic memory is formed and stored is challenging in both humans and animals.
- A study using a new task in rodents demonstrates that rats can create and remember integrated remote episodic memories, showing variations in memory content and accuracy based on their emotional ties to specific odors.
- Advanced brain imaging revealed that activated brain networks involved in recollecting these memories reflect their nature and content, highlighting the importance of both a cortico-hippocampal network for complete recollection and an emotional network related to odors for maintaining vivid memories.
Article Abstract
Memories of life episodes are the heart of individual stories. However, modelling episodic memory is a major challenge in both humans and animals when considering all its characteristics. As a consequence, the mechanisms that underlie the storage of old nontraumatic episodic memories remain enigmatic. Here, using a new task in rodents that models human episodic memory including odour/place/context components and applying advances behavioural and computational analyses, we show that rats form and recollect integrated remote episodic memories of two occasionally encountered complex episodes occurring in their daily life. Similar to humans, the information content and accuracy of memories vary across individuals and depend on the emotional relationship with odours experienced during the very first episode. We used cellular brain imaging and functional connectivity analyses, to find out the engrams of remote episodic memories for the first time. Activated brain networks completely reflect the nature and content of episodic memories, with a larger cortico-hippocampal network when the recollection is complete and with an emotional brain network related to odours that is critical in maintaining accurate and vivid memories. The engrams of remote episodic memories remain highly dynamic since synaptic plasticity processes occur during recall related to memory updates and reinforcement.
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| http://dx.doi.org/10.1016/j.pneurobio.2023.102422 | DOI Listing |
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