I challenged Dr. R.P. to try and forget what I told him

Many of us value a good memory and, if given a chance, would work at improving our ability to remember. Just talk to oldies and they will lament their slipping memory ability and ask you what might help.

I would put in a request that would help me forget things I wish I didn’t remember, especially memories that are emotionally toxic.

A number of strategies can be used to increase the likelihood that we will remember some fact or event. Active rehearsal, associating a to-be-remembered event with some other piece of knowledge like a name and face with a scene that has made a strong impression on us (a form of rehearsal), or being told we will be rewarded if we remember some event, or fact. Perhaps there are also some drugs that may have a small effect on improving our memory.

What about treatments that aid forgetting? Are there not some biographical events that have had a profound effect on you, an impact that is quite negative, perhaps even crippling, and would you consider having that memory erased? Regardless of how you would answer that question, I would point out that we really don’t know how to erase a specific memory, knowledge that is well etched in our brain.

Dr. R.P. is a famous neuroscientist who has studied the causes and treatment of affective disorders. I first met him at a scientific conference in the late spring of 1975, over 30 years ago. We quickly became good friends, colleagues. We also got a chance to see each other at conferences and on visits to our respective  home institutions. At the conference where we first met I challenged R.P. to try and forget a piece of information that I presented to him in the form of a little scene, an image. I told him the following. “R.P. I want you to picture a prestidigitator (magician/juggler) sitting on an elephant tossing little colored balls (maybe the size of billiard balls), up in the air and catching them. He is dressed rather like a clown, and on his head is a small hat……that is it…now concentrate on that image” which R.P. did for about 20 seconds and that was it. I told him that he will not be able to forget that image, never, ever. We both laughed about our ‘experiment’ in remembering or forgetting.

Two years later we met and I asked, “OK. What were you supposed to remember?” and without hesitation R.P. described the scene in his head, adding a bit of vegetation around the elephant. It was just enough reactivation of the ‘elephant story’ to keep it alive in memory. And so it went for a couple of decades.  Every few years I would ask R.P. whether he could remember what I said he could never forget and out came the mental image of the elephant and prestidigitator. R.P. never failed to remember. Neither of us was surprised.

We next turned our attention to treatments that might be effective in getting him to forget all about the elephant and the prestidigitator, or perhaps treatments that might significantly distort or change the image he had in his head for 25 or more years. In our discussion we talked about drugs, but these were likely to create a temporary but not a permanent amnesia. We did consider a steady diet of toxic agents like years of alcohol abuse, but even such a drastic intervention would affect current memory formation but not remembering experiences prior to decades of alcohol abuse. We thought about creating highly specific brain lesions but soon realized these would be unreliable since we could affect memory in a very general way but could not ‘cut out’ the memory we wanted to eliminate.  We turned to much more massive brain surgery, removing much of his brain, and once again we might successfully remove from memory our to-be-remembered event but at the expense of lots of other mental functions. I guess we could wait for him to develop a dementia and then wait for it to progress far along and then ask again, “What did I ask you to remember that I told you I didn’t think you could forget?” We are both much older and still struggle with ways for R.P. to forget the scene, or at least have the prestidigitator fall off the elephant and disappear into the bush.

Dear R.P.,

I guess we gave up to soon. Can’t blame us for giving up to soon. After all we have been at the task of erasing the memory of your prestidigitator on the elephant for 30 years, and all we could come up with is taking out most of your brain. Both of us have been following the search for a memory engram, or a molecule or two that can be critical in forming and retaining memories. Lots of candidate molecules have been discovered but none that can actually erase a specific memory like your elephant scene. Turns out that a neuroscientist, Todd Sacktor (at SUNY Downstate Medical Center in Brooklyn N.Y.) claims to have discovered such a molecule that can erase specific memories in the rat. He is part of a research group that includes Peter Serrano and Andre Fenton who have investigated the details of how a protein PKMζ is key in how long term memories are stored in the rat brain(see paper in PLoS Biol. 6(12) Dec. 2008). Wow…are we getting closer? Do you think it may be for real? Should we talk to these guys?