It is not known for certain whether modern cryopreservation preserves “enough”, partly because we are not entirely sure how long-term memories and personality are actually stored. We do know that the connectome is preserved, and modern techniqued such as aldehyde-stabilized cryopreservation seem to preserve cell membranes, synapses, and intracellular structures. See Wikipedia and the relevant paper.
It is possible that some key piece of information is destroyed by these protocols, with no way of recovery. Everything that we know is required to be preserved, is preserved.
Given that c. elegans survived vitrification, it’s not surprising that its memory persisted, though it does underline the point that memory is not some kind of magic—it’s physically recorded. Of course large mammals like humans are very different from c. elegans.
Given that
humans survive immersion in freezing water and 60 minutes of brain death with their memories intact
c elegans survives full vitrification with memories intact
connectome information and intercellular structure survives aldehyde stabilised cryopreservation
we can conclude that the skeptical case is trying to thread through an ever narrower gap. If you claim that the physical correlates of memory are too delicate, you contradict existing results. If you claim they are too robust, you are forced to conclude that they are preserved by the best cryo.
It is not known for certain whether modern cryopreservation preserves “enough”, partly because we are not entirely sure how long-term memories and personality are actually stored. We do know that the connectome is preserved, and modern techniqued such as aldehyde-stabilized cryopreservation seem to preserve cell membranes, synapses, and intracellular structures. See Wikipedia and the relevant paper.
It is possible that some key piece of information is destroyed by these protocols, with no way of recovery. Everything that we know is required to be preserved, is preserved.
There’s also “Persistence of Long-Term Memory in Vitrified and Revived C. elegans”, Vita-More & Barranco 2015 - so we know that in at least one species (which did not evolve for being frozen) that long-term memory is preserved by the best cryonics techniques.
Given that c. elegans survived vitrification, it’s not surprising that its memory persisted, though it does underline the point that memory is not some kind of magic—it’s physically recorded. Of course large mammals like humans are very different from c. elegans.
Given that
humans survive immersion in freezing water and 60 minutes of brain death with their memories intact
c elegans survives full vitrification with memories intact
connectome information and intercellular structure survives aldehyde stabilised cryopreservation
we can conclude that the skeptical case is trying to thread through an ever narrower gap. If you claim that the physical correlates of memory are too delicate, you contradict existing results. If you claim they are too robust, you are forced to conclude that they are preserved by the best cryo.