Tansfer of memory in flatworms (Planarians) and rats
The finding that when trained flatworms (planarians) are fed to untrained worms, the untrained worms behave as though they have learned the task is called memory transfer or behavior induction.
It has been suggested in THE STRAIGNT DOPE that when trained worms are fed to untrained worms, some sort of "general factor" is actually transferred to the untrained worms and that this chemical factor "prepares worms to learn faster" or facilitates learning. That is, it has beens uggested that memory is not actually transferred, only a tendency to learn faster.
This interpretation for the well-documented findings of transfer of memory by cannibalism in flatworms ignores the observation that when untrained worms are fed trained worms, they do not just learn faster—they begin the task (e.g., classical conditioning) by performing as though they already have learned the task. They do not just learn faster, they make conditioned responses on the very first learning trial.
Although James McConnell and Robert Thompson, ho discovered these findings, interpreted their findings as supportive of the view that memory is chemical in nature and can be transferred from one wprm to another, no single interpretation of these findings (replicated even by high school students) has never been generally accepted and the phenomenon has never fully explained.
Scientists have repeated these findings using RNA-rich brain extracts from trained rats and using untrained rats as recipients, and replicated the effect found in the worm experiments. All these experiments have been so controversial that funding became unavailable to continue the research and scientists moved on to other research topics without ever adequately explaining any of these findings found in the worm and the rat and mouse experiments.