Page 233 - The Memory Program How to Prevent Memory Loss and Enhance Memory Power

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A large part of the human genome, or genetic map, focuses on controlling protein synthesis within
the brain. As of now, we do not know which genes are responsible for triggering the process of
neuronal degeneration and death in the hippocampus and frontal lobes, or for that matter any other
part of the brain. It is likely that we all possess both ‘‘good memory genes” and “bad memory
genes,” and once we discover them we will be able to directly tackle the problem of age-related
memory loss that affects most of us as we grow older.

CREB and Knockout Mice

A memory trace is solidified if there is a small gap in time between the pieces of information that
need to be remembered. Using this technique, which is called spaced training, scientists engineered a
fruit fly to have a photographic memory. In the same fruit fly species, they triggered a master gene
called CREB, which has the ability to goad a number of other genes into action. In this manner, the
fruit fly with a fabulous memory was born. Ideally, if we could stimulate CREB in the same way in
the human brain, total recall would become the standard for everyone. But there is no known method
to turn a gene on or off in the human brain, so even though we all possess CREB, we don't yet know
how to galvanize it into action in people. The goal of these researchers is to see if manipulating
CREB in some fashion will make it possible to unlock the full power of human memory.

Other researchers like Eric Kandel approach the same problem from a different angle. He takes
mice and removes, or knocks out, a gene or set of genes that are involved in cognitive processes.
These “knockout” mice perform horribly in mazes and similar tests of cognitive ability. Drugs are
then administered, one by one, to see if they can reverse this glaring memory deficit in the knockout
mice. One such promising agent is rolipram, but as yet there are no worthwhile clinical studies with
this compound. Another strategy is to block the synthesis of specific proteins by genetic
manipulation, which then leads to memory loss in rats. As with the knockout mice, specific drugs
can be given to reverse this process and correct the memory deficit. Kandel, in his dynamic way, has
formed his own company to employ these techniques to try and find the magic pill that will reverse
memory loss.