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

To uncover the answer, research assistant Kelso ventured to the Charles River in search of wild planarian worms, the simplest creatures with a brain and nervous system. Despite his efforts, these worms did not respond to conditioning. Kelso then turned to other sources, even trying to catch them in Michigan lakes while enduring chilly waders and ignoring onlookers.

But still, none of the planarians would learn. This led scientists, like neuroscientist Sam Gershman of Harvard, to revisit the 1960s experiments of eccentric psychologist James McConnell. McConnell had convinced the scientific community that planarian worms could be classically conditioned and that their memories could be transferred through cannibalism.

However, recent attempts to replicate these findings have failed. Gershman, intrigued by the possibility of finding clues to memory origins beyond the brain, joined forces with McConnell's lab. They aimed to reproduce McConnell's bizarre worm experiments, despite no success thus far. Planarians possess impressive regenerative abilities, capable of regrowing into a full worm from as little as 1/279 of their original size.

McConnell’s experiments involved chopping trained worms into smaller pieces, and surprisingly, the regenerated segments retained their memory. He even tried feeding trained-worm puree to other worms through cannibalism, and the cannibals learned the light response. The notion that memory might be encoded physically, rather than just in the brain, was plausible during McConnell's time.

However, the current inability to replicate McConnell's results leaves the true nature of planarian memory still shrouded in mystery.