Single events account for many of our most vivid memories – a marriage proposal, a wedding toast, a baby’s birth. Until a recent UC Irvine discovery, however, scientists knew little about what happens inside the brain that allows you to remember such events.
In a study with rats, neuroscientist John Guzowski and colleagues found that a single brief experience was as effective at activating neurons and genes associated with memory as more repetitive activities.
Knowing how the brain remembers one-time events can help scientists design better therapies for diseases such as Alzheimer’s in which the ability to form such memories is impaired.
“Most experiences in life are encounters defined by places, people, things and times. They are specific, and they happen once,” says Guzowski, UCI neurobiology and behavior assistant professor. “This type of memory is what makes each person unique.”
It is well known that a brain structure called the hippocampus is critical to memory and learning, but many questions exist about how brief experiences trigger the physical changes necessary for memory. In his study, Guzowski set out to learn how neurons in the hippocampus react to single events – particularly in the CA3 region, which is thought to be most critical for single-event memory.
Guzowski and postdoctoral researcher Teiko Miyashita put groups of rats on a rectangular track. Some rats took one lap; others did multiple laps. Inspecting the brains of rats that took one lap, they found that 10-15 percent of neurons in the CA3 region activated. The same percentage of CA3 neurons fired in the brains of rats that walked multiple laps.
Though previous computer simulations predicted that brief and repetitive experiences would activate CA3 neurons similarly, this is the first study to actually show that is the case.
Miyashita and Guzowski arrived at the percentages by examining the activation of a gene called “Arc” within hippocampal neurons. Past studies have shown that turning on Arc is required to convert experience into long-term memory.
“Together with our past findings, this study provides key insight into how fleeting experiences can be captured by the brain to form lasting memories,” Guzowski says.
Arc activation is disrupted in mouse models of mental retardation and Alzheimer’s disease.
“Our findings on Arc regulation in CA3 neurons should prove useful to researchers testing new therapies for Alzheimer’s disease,” Guzowski says. “If you understand how the hippocampus works, it is much easier to understand and potentially treat diseases that affect memory.”
UCI researchers Stepan Kubik, Nahideh Haghighi and Oswald Steward also worked on this study, published in The Journal of Neuroscience. The National Institutes of Health supported this research.
About the University of California, Irvine: UCI is a top-ranked university dedicated to research, scholarship and community service. Founded in 1965, UCI is among the fastest-growing University of California campuses, with more than 27,000 undergraduate and graduate students, 1,100 faculty and 9,200 staff. The top employer in dynamic Orange County, UCI contributes an annual economic impact of $4.2 billion. For more UCI news, visit www.today.uci.edu.
News Radio: UCI maintains on campus an ISDN line for conducting interviews with its faculty and experts. Use of this line is available for a fee to radio news programs/stations that wish to interview UCI faculty and experts. Use of the ISDN line is subject to availability and approval by the university.
Jennifer Fitzenberger | EurekAlert!
Some brain tumors may respond to immunotherapy, new study suggests
11.12.2018 | Columbia University Irving Medical Center
Climate change and air pollution damaging health and causing millions of premature deaths
30.11.2018 | International Institute for Applied Systems Analysis (IIASA)
The more objects we make "smart," from watches to entire buildings, the greater the need for these devices to store and retrieve massive amounts of data quickly without consuming too much power.
Millions of new memory cells could be part of a computer chip and provide that speed and energy savings, thanks to the discovery of a previously unobserved...
What if, instead of turning up the thermostat, you could warm up with high-tech, flexible patches sewn into your clothes - while significantly reducing your...
A widely used diabetes medication combined with an antihypertensive drug specifically inhibits tumor growth – this was discovered by researchers from the University of Basel’s Biozentrum two years ago. In a follow-up study, recently published in “Cell Reports”, the scientists report that this drug cocktail induces cancer cell death by switching off their energy supply.
The widely used anti-diabetes drug metformin not only reduces blood sugar but also has an anti-cancer effect. However, the metformin dose commonly used in the...
A research team from the University of Zurich has developed a new drone that can retract its propeller arms in flight and make itself small to fit through narrow gaps and holes. This is particularly useful when searching for victims of natural disasters.
Inspecting a damaged building after an earthquake or during a fire is exactly the kind of job that human rescuers would like drones to do for them. A flying...
Over the last decade, there has been much excitement about the discovery, recognised by the Nobel Prize in Physics only two years ago, that there are two types...
12.12.2018 | Event News
10.12.2018 | Event News
06.12.2018 | Event News
14.12.2018 | Power and Electrical Engineering
14.12.2018 | Physics and Astronomy
14.12.2018 | Physics and Astronomy