Unlocking the Mystery of Memories

Scientists have long tried to understand how the brain makes memories, but were, until now, frustrated by their inability to look at the workings of individual neurons.  

Dr. Hyungsik Lim, an assistant professor of physics at Hunter College, contributed to a recent study, published in Science, in which scientists observed fluorescently tagged messenger RNA (mRNA) molecules-a key component in the making of memories-as they traveled through the brain of a genetically engineered mouse. The observations were made with the use of an imaging technique known as two-photon microscopy. 

"Although this technique has been used to learn a lot about how neurons work, it has always been on the cellular level," said Dr. Lim. "Never before has it been used to observe single mRNA molecules."

In addition, this is the first time this technology has been demonstrated in a live animal.  

Beyond a better understanding of memory, the study could open the door to a host of medical advances. "For instance," said Dr. Lim, "it is well-known that mRNA is implicated in Fragile X syndrome [a genetic condition that causes learning disabilities and cognitive impairment] and evidence suggests significant roles in other neurological disorders such as Alzheimer's disease. 

"By studying mRNA dynamics in living animals," Lim adds, "we can understand how these conditions arise and such knowledge could lead to new therapies."

Read press coverage of the study in Science Codex and Health Canal.