The researchers studied a gene that normally increases levels of a natural memory-blocking protein. Animals that carry a defective version of this gene showed improved performance in classical behavioral memory tests, they show. Moreover, animals treated with a small molecule that had the opposite effect—leading ultimately to an increase in the memory-blocker's concentration—showed signs of memory impairment.
"There are very few examples where you can increase memory, especially by deleting genes," said study author Nahum Sonenberg of McGill University in Montreal, Canada. "It's a small, but important part of the big puzzle of how memory works.?
"The next step, which is inevitable, is to look for small molecules that mimic this memory-enhancing effect," he continued.
"If such a pill could be generated, it might provide a new method for treating people with memory-related diseases such as Alzheimer's," said Mauro Costa-Mattioli, a senior postdoctoral fellow in Sonenberg’s laboratory. "While a drug that worked in this way wouldn't cure the disease itself, it might rescue the symptoms of memory loss."
Memories are formed when the repeated activation of brain cells leads to a strengthening of neural connections, or synapses. This process, considered the cellular basis of learning and memory, is known as synaptic plasticity.
Both memory and synaptic plasticity have two components, the researchers explained. One, which is evoked by weak training protocols, yields only transient phenomena—including short-term memory, lasting for minutes to hours, or the beginning stages of longer-term memory storage, lasting for one to three hours.