Francis Crick and the long-term storage of the memory trace
Since my Ph.D. is related to memory consolidation, I was interested in a strange idea from Francis Crick. He asked the question of long-term storage of the memory trace 1. How is this memory trace stored in our brain? And, more importantly, how is it protected against molecular turnover? In his view, Crick suggested three hypothesis: Memory could be encoded in alterations of some part of the cell DNA. This will imply that each neuron synapse would be represented by a part of the neuron DNA since the actual paradigm states that memory is encoded in the strength of individual synapse. This first hypothesis seems unlikely. Memory could otherwise be stored in a local piece of DNA or RNA, at the synapse (a bit like the mitochondrion has its own DNA). This piece would be immune to the molecular turnover. Although more logical, this hypothesis seems unlikely too. Finally, Crick’s last hypothesis states that molecules at the synapse level would interact in such a way they could be replaced by new ones, one at a time, without altering the general status (strength). The figure below shows a working example of this hypothesis … ...