The researchers contend the technique allows scientists and engineers to, for the first time, visualize mRNA molecules in the brains of living mice, providing insights into how memories are formed and stored in the brain and potentially providing new information about memory-related diseases such as Alzheimer's disease.

A paper, published on July 1 in the Proceedings of the National Academy of Sciences, describes the team's process which involved genetic engineering, two-photon excitation microscopy, and optimized image processing software. By genetically modifying a mouse so that it produced mRNA labeled with green fluorescent proteins (proteins derived from a jellyfish), researchers were able to see when and where the mouse's brain generated Arc mRNA.

"We still know very little about memories in the brain," said Hye Yoon Park, PhD, the study's lead author and an associate professor in the University of Minnesota Department of Electrical and Computer Engineering. "It's well known that mRNA synthesis is important for memory, but it was never possible to image this in a live brain. Our work is an important contribution to this field. We now have this new technology that neurobiologists can use for various different experiments and memory tests in the future."