Viagra: Part 1 - Companies selling the herbal supplement gingko
biloba say it can enhance your memory. But scientific evidence
on whether gingko works has been controversial at best. (4/21/03)
Teeth Boost Memory - A memory researcher says we can manipulate
emotion to help improve our memory. (2/19/03)
Elsewhere on the web
for the Brain - Forbes.com
Switch Memory Recall On and Off in Fruit Flies - CSHL
enhancement: the search for mechanism-based drugs - Nature
Thereâ€™s a huge market for substances that claim to boost memory, but
when can we expect drugs designed and proven to do that?
As this ScienCentral News video reports, advances in genetics research may
be helping to make effective memory drugs a reality.
Shocking Fruit Flies
Most animals have the ability to remember past experiences. So scientists
are studying how they learn and remember things, in order to ultimately make
drugs that can enhance human memory.
“We now know from the work of many different labs that the genes involved
in different aspects of learning and memory are the same genes in fruit flies,
in marine invertebrates, in mice and rats, and most certainly in humans,”
Dubnau, assistant professor at Cold
Spring Harbor Laboratory.
Dubnau, along with Tim
Tully, taught fruit flies, each one genetically engineered to lack a different
gene, to associate an odor in a tube with an electric shock. “We give
them a little foot shock whenever they smell one odor,” explains Dubnau,
“and they can learn that that odor predicts something nasty, a foot
shock, and in the future they will avoid that odor if given the opportunity.”
Nearly all 6,000 flies in the experiment learned to avoid that smelly tube.
If one of the flies did not learn to avoid the shocking odor, the researchers
figured the gene it was missing must be important to memory.
Dubnau also used high-tech “gene chips”—which can quickly
determine which genes are active, or “turned on” in an animal
while it is performing a certain task—to find more genes that were active
in the fruit flies during learning and memory. As Tully and Dubnau reported
in the journal Current
Biology, all told they were able to find a total of 92 such “memory
“We can now take each one of these genes that weâ€™ve identified
and use the tool box of techniques that is available in order to try and understand
how these genes function during memory formation,” says Dubnau.
Rats Studied Too
Alkon, a biophysics research professor at the Blanchette
Rockefeller Neurosciences Institute, studied the memory genes of rats.
The rodents were first were trained in the Morris
Water Maze wherein the rat has to find a platform submerged in a tub of
water. After several trials, the rat learns to find the platform very quickly.
Then Alkon used gene chips to analyze the gene activity in tissue samples
from the rats, to see which genes among thousands were active during the learning
process. Using the gene chips, Alkon found 140 genes that he considered crucial
to learning and memory. But there was more.
“Even though we did see many [genes] that changed in different periods,”
says Alkon, “we only saw one that changed consistently throughout the
entire process. And that was a gene that codes for a protein called the ‘fibroblast
Since this one protein was changing throughout the ratsâ€™ entire learning
and memory process, Alkon and his team wanted to see if it had a direct effect
on memory. They injected this protein into ratsâ€™ brains, and then put
them back into the Morris Water Maze. They reported
in the Proceedings of the National Academy of Science, that the
rats that had been injected with the protein doubled their retention of where
the submerged platform was—their memories were twice as sharp as the
memories of rats that were not injected with the protein.
“That approach—from gene, to protein, to drug for the protein—represents
a kind of paradigm that may be valuable for a variety of cognitive disorders
in the 21st century,” says Alkon.
Both Dubnauâ€™s and Alkonâ€™s research offer new avenues to explore
in the quest for a memory drug for humans, which would help millions, especially
the aging. “There are many types of age-related changes that people
donâ€™t like, that affect the way we function, and that people think nothing
about doing something about,” says Steven
Ferris of the Institute
for Aging & Dementia at NYU Medical School. “We have drugs to
stop hair loss. Everyone over a certain age wears glasses that allow you to
see print close up. Many people when they get older need hearing aids. There
are many other treatments for a host of age-associated declines that people
experience that we think nothing about doing something about. Why not do the
same for memory?”