Dynamic memory maintenance

Memories can be maintained for very long periods of time, even during our whole lifetime. A fundamental dogma in the Neurosciences is that memories are engraved in the brain via specific, long-term, alterations in synaptic efficacies. However, synaptic turnover is relatively widespread in the mature nervous system1,2,3. How then are memories maintained for very long periods? Clearly memories can be maintained if synaptic weights can be kept fixed, which is the purpose of several mechanisms that were suggested in the literature. An interesting alternative, that we will explore below, is maintaining memories with altered synaptic values, i.e., synapses change dynamically and still encode the original memories4.

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