Are Memories Transferable? Meet the Scientists Replicating an Infamous Study to Find Out

The potential for memory transfer in simple organisms is being revisited, which could fundamentally alter our understanding of learning and memory.

Scientists are attempting to replicate controversial 1960s experiments suggesting that memories could be transferred between planarian worms through cannibalism. These original studies, conducted by James McConnell, claimed that flatworms could be conditioned to associate a light with a shock, and that this learned response could be passed to other worms by feeding them purified, trained worms. McConnell believed memories were encoded in RNA. The findings were widely publicized but faced replication issues and were eventually sidelined as scientific interest shifted to other models. Harvard neuroscientist Sam Gershman's lab, employing a research assistant named Kelso, is now trying to reproduce these experiments with wild-caught planarians. However, Kelso has struggled to find worms that exhibit the expected learning behaviors, and the lab's current attempts to train planarians have thus far been unsuccessful. The original experiments were published in McConnell's unconventional journal, The Worm Runner's Digest, contributing to his reputation as a maverick scientist.

The current scientific endeavor to replicate McConnell's work seeks to validate or debunk a decades-old claim that has significant implications for neuroscience. If successful, it would suggest that memory is not solely dependent on complex neural structures, but may indeed have a transferable biochemical basis, as McConnell hypothesized. This could open new avenues for research into memory storage and retrieval, potentially impacting fields ranging from artificial intelligence to therapeutic interventions for memory disorders.

The challenges faced by Kelso in sourcing and training worms highlight the difficulties inherent in replicating historical findings, especially when original methods and materials are no longer readily available or standardized. The renewed interest in planarian memory research, spurred by Gershman's lab, indicates a growing curiosity about non-neuronal forms of memory, driven by advancements in understanding cellular memory and the regenerative capabilities of organisms. This resurgence could reignite debates about the nature of engrams and the biological underpinnings of consciousness.