Turning Moments into Memories

Researchers at Wake Forest University have come closer to
explaining how fleeting moments are sealed into life-long memories. Ashok
Hegde, assistant professor at WFU Baptist Medical Center in
Winston-Salem, North Carolina, along with colleagues, is mapping out the
pathway that leads experiences to become long-term memories in
mice.

For humans to store memories in the brain's keepsake box, "we must
either get information repeatedly or strongly," Hegde explains. "One of
the hallmarks of memories that last is a close association with emotion."
Norepinephrine, a brain chemical similar to adrenaline, is released in
the brain during such emotional situations. "Norepinephrine lowers the
gate so that information can go into permanent storage," Hegde says."The
details might be different in mice and people, but we think the mechanism
will be the same."

When a female mouse mates with a male mouse, she memorizes her
partner's scent. Even if she mates with him only once, she can recognize
his scent up to 50 days later. The researchers discovered than an enzyme
known as protein kinase C played a fundamental role in converting the
experience into a long-term memory, by activating genes and stimulating
protein synthesis necessary to build the connections between nerve cells
that underlie memories.

Hegde presented the research at the annual meeting of the Society
for Neuroscience in New Orleans. He is now using sophisticated computer
programs to identify the specific "memory genes" in mice.