The curious mysteries of memory


John Kizer



Because of family commitments, I am rarely able to watch TV. But a few months ago, I received an email notifying me that “Jeopardy!” was looking for contestants, and that I could take an online test which is the first hurdle to getting on the show. I am not at all a trivia expert, not even close. Nevertheless, I thought it might be fun to try.

So I took the test, after which I felt it was pretty much a lost cause. Somehow, though, I did pass. This does not mean that I will be on the show. In fact, after watching the next few episodes, it might be a blessing if I am not chosen. It might save me some embarrassment. If I should make it, I’ll make it fun, win or lose.

The test, like the show, demands quick recall of things which one may not have thought of in years, or even decades. How is it that we remember things that we haven’t thought of in years? How is memory stored in the brain? That was the very first scientific problem which ever engaged me, many years ago. We called it the “search for the engram” in those days. The engram was the memory trace.

To this day, the solution to the problem of memory has been too daunting for neuroscience. There is no consensus, even conceptually. Science is often taught as though all the big ideas are agreed upon, and the only work remaining to be done by the scientist is to calculate or refine a measurement to the 10th decimal point. That is by no means true. There is still room for new big ideas in science, and there should be a Nobel Prize awaiting the young, or old mind which solves the problem of learning and memory — that is, figures out their physiological, cellular or molecular bases.

Todd Sacktor, one of the world’s leading neurologists has called memory “the last of the great 20th century problems in biology.” Certainly with the world’s aging population and that population’s associated losses of memory, an understanding of how to mitigate that loss would be of the greatest practical importance.

Old experiments by Karl Lashley indicated that large and different parts of a rat’s brain could be destroyed, and the rat would still retain some memory of how to run a maze. Memories seemed to be stored throughout the brain. A more recent analogy was that the brain was like a hologram in which all the information is contained everywhere. Other old experiments by Wilder Penfield found that specific memories could be stimulated by electrically stimulating localized parts of the human brain. This conflict between localized storage and generalized storage of memory has never been completely resolved.

Recent experiments by UCLA neuroscientists suggest that memory can be transferred by RNA, at least in snails, and that old memories might even be recoverable by injections of RNA. This hearkens back to the experiments of James McConnell in the 1960s, in which he would teach planarians (flatworms) to run a maze, then feed them to other flatworms, and those flatworms seemed to know how to run the maze. McConnell also thought RNA was the memory molecule.

In my callow youth, I tried to replicate McConnell’s work, but I had trouble training the planarians to run the maze or even determining whether the “trained” planarians or their cannibals had learned the maze. Science can be messy and is often not so clear cut as it seems to be in the news. It could be that my experimental technique was faulty, or I may have been given some of the Kallikaks of the planarian world.

Of course, memory in flatworms, or snails, may be entirely different from memory in humans. Nevertheless, if I should get on “Jeopardy!” and lose to some whiz who seems to remember everything, I think I may demand a drug test to see if he or she has received any recent massive injections of RNA. That is, if I don’t forget to do so.

John Kizer

John Kizer has been published by the Foundation for Economic Education, and some of his submissions have been included in The Encyclopedia of Freedom. Kizer, who lives in Portsmouth, was a National Science Foundation Fellow in cell biology “more decades ago than I care to count,” and the research to which he refers in this column was done before his association with the NSF.

John Kizer has been published by the Foundation for Economic Education, and some of his submissions have been included in The Encyclopedia of Freedom. Kizer, who lives in Portsmouth, was a National Science Foundation Fellow in cell biology “more decades ago than I care to count,” and the research to which he refers in this column was done before his association with the NSF.

RECOMMENDED FOR YOU