Study uncovers memory formation mechanisms in mouse brain

Researchers have made new discoveries about how memories are formed in the mouse brain. This study was supported by the National Institutes of Health (NIH) and highlights the flexible nature of memory creation. The findings show that neurons involved in forming memories reorganize their connections. This happens through a unique structure called a multi-synaptic bouton, where one neuron connects to several other neurons. This could help explain why memory functions can sometimes become impaired. The study also challenges the traditional idea that neurons strengthen their connections by firing together. Instead, it found that memory-forming neurons were not particularly connected to each other. Additionally, these neurons changed their internal structures related to energy and communication, showing enhanced interactions with support cells known as astrocytes. Using advanced genetic tools and 3D electron microscopy, scientists from Scripps Research created detailed images of the neuronal networks associated with learning. They focused on the hippocampus area of the brain about a week after exposing mice to a learning task. This comprehensive research provides insight into the cellular aspects of memory formation. It opens up new questions about whether similar processes occur in other brain regions and timeframes. Future studies will be important for understanding the role of multi-synaptic boutons in memory and cognition.