Memory transfer

Memory transfer was a biological process proposed by James V. McConnell and others in the 1960s. Memory transfer proposes a chemical basis for memory termed memory RNA which can be passed down through flesh instead of an intact nervous system. Since RNA encodes information[1] living cells produce and modify RNA in reaction to external events, it might also be used in neurons to record stimuli.[2][3][4] This explained the results of McConnell's experiments in which planarians retained memory of acquired information after regeneration. Memory transfer through memory RNA is not currently a well-accepted explanation and McConnell's experiments proved to be largely irreproducible.[5]

In McConnell's experiments, he classically conditioned planarians to contract their bodies upon exposure to light by pairing it with an electric shock.[6][5] The planarians retained this acquired information after being sliced and regenerated, even after multiple slicings to produce a planarian where none of the original trained planarian was present.[5] The same held true after the planarians were ground up and fed untrained cannibalistic planarians, usually Dugesia dorotocephala.[5][7] As the nervous system was fragmented but the nucleic acids were not, this seemed to indicate the existence of memory RNA[5] but it was later suggested that only sensitization was transferred,[6] or that no transfer occurred and the effect was due to stress hormones in the donor or pheromone trails left on dirty lab glass.[2] However, other experiments seem to support the original findings in that some memories may be stored outside the brain.[1][8][9]

  1. ^ a b Cite error: The named reference Reckoning was invoked but never defined (see the help page).
  2. ^ a b Bob Kentridge. "Investigations of the cellular bases of memory". University of Durham. Archived from the original on 2012-10-15. Retrieved 2011-03-03.
  3. ^ McFarling,STAT, Usha Lee. "Memory Transferred between Snails, Challenging Standard Theory of How the Brain Remembers". Scientific American. Retrieved 2019-03-10.
  4. ^ Dave, Shivani (2018-05-14). "'Memory transplant' achieved in snails". Retrieved 2019-03-10.
  5. ^ a b c d e "The memory-transfer episode". www.apa.org. Retrieved 2021-02-05.
  6. ^ a b William L. Mikulas. "Physiology of Learning". University of West Florida. Archived from the original on 2017-11-27. Retrieved 2011-03-03.
  7. ^ James, McConnell (1965). "A Manual of Psychological Experimentation on Planarians" (PDF). The Worm Runner's Digest: 5, 7 – via https://www.tufts.edu/. {{cite journal}}: External link in |via= (help)
  8. ^ Duhaime-Ross, Arielle (17 September 2013). "Flatworms Recall Familiar Environs, Even after Losing Their Heads". Scientific American. Retrieved 18 March 2015.
  9. ^ Shomrat T, Levin M (2013-07-02). "An automated training paradigm reveals long-term memory in planaria and its persistence through head regeneration". The Journal of Experimental Biology. 216 (20): 3799–3810. doi:10.1242/jeb.087809. PMID 23821717.