Memorizing stuff also boosts neural connectivity

May 27, 2009 08:54 GMT  ·  By
Synapses grow stronger in CA3 neurons, as more single event memories are stored
   Synapses grow stronger in CA3 neurons, as more single event memories are stored

For quite some time now, experts have wondered how exactly it is that the human brain is able to store memories of single events, and to recall them at a moment's notice. Over the years, they have noticed that the emotional response this type of memories draws from people is almost identical to the one incited by very strong memories of multiple events. Experts at the University of California in Irvine (UCI) have recently managed to shed some light on that, showing approximately what goes on in our head when the brain stores these single events.

For example, in a study conducted on unsuspecting mice, researchers learned that the effects of single memory events on the brain of the little animals were just as successful in activating genes and neurons associated with memory as more repetitive actions. Neuroscientist John Guzowski, the leader of the UCI research team, said that understanding how these memories were stored could potentially hold much-needed clues for the development of novel therapies, for conditions such as Alzheimer's.

“Most experiences in life are encounters defined by places, people, things and times. They are specific, and they happen once. This type of memory is what makes each person unique,” the researcher said. He is also an assistant professor of neurobiology and behavior at the university.

“Together with our past findings, the present study provides key insight into how fleetingly brief experiences can be captured by the brain to form lasting memories.” The investigator worked closely with UCI postdoctoral researcher Teiko Miyashita for the new research, which was published in a recent issue of the respected Journal of Neuroscience.

From past studies, the team knew that the hippocampus played a crucial part in storing memories, but they had no idea as to the mechanisms this region of the brain employed in order to respond to the faint signal of single events. Scientists are aware of the fact that the brain basically goes through a physical modification when storing memories, and they wondered how come the single events had so much “impact” that they were recorded almost flawlessly. They learned that the CA3 region was the most receptive and sensitive to single events.

The team also noticed that the gene called Arc varied in quantities with the subjects' abilities of recollecting single events. “Our findings on Arc regulation in CA3 neurons should prove useful to researchers testing new therapies for Alzheimer's disease. If you understand how the hippocampus works, it is much easier to understand and potentially treat diseases that affect memory,” Guzowski concluded, PhysOrg reports.