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David runs his lab at UCLA where he's also a distinguished professor.  David used to believe what is currently the mainstream view, that our memories are stored in our synapses, those connections between our neurons.  So as we learn, the synaptic connections strengthen and weaken until their just right, and that serves to preserve the memory. That's been the dominant view in neuroscience for decades, and is the fundamental principle that underlies basically all of deep learning in AI. But because of his own and others experiments, which he describes in this episode, David has come to the conclusion that memory must be stored not at the synapse, but in the nucleus of neurons, likely by some epigenetic mechanism mediated by RNA molecules. If this sounds familiar, I had Randy Gallistel on the the podcast on episode 126 to discuss similar ideas, and David discusses where he and Randy differ in their thoughts. This episode starts out pretty technical as David describes the series of experiments that changed his mind, but after that we broaden our discussion to a lot of the surrounding issues regarding whether and if his story about memory is true. And we discuss meta-issues like how old discarded ideas in science often find their way back, what it's like studying non-mainstream topic, including challenges trying to get funded for it, and so on.

• David's Faculty Page.
• Related papers
  • The central importance of nuclear mechanisms in the storage of memory.
  • David mentions Arc and virus-like transmission:
    • The Neuronal Gene Arc Encodes a Repurposed Retrotransposon Gag Protein that Mediates Intercellular RNA Transfer.
    • Structure of an Arc-ane virus-like capsid.
• David mentions many of the ideas from the Pushing the Boundaries: Neuroscience, Cognition, and Life  Symposium.
• Related episodes:
  • BI 126 Randy Gallistel: Where Is the Engram?
  • BI 127 Tomás Ryan: Memory, Instinct, and Forgetting