Researchers Find Out How Teams of Neurons Help You Form Strong Memories
Many people, especially the elderly, have experienced situations where they find it hard to recall information they had only just learned, despite being able to recall older memories.
A new study by researchers at California Institute of Technology has shed some light on why this may happen.
The ability to recall information is a highly crucial one. An inability to do so can be rather distressing not only for the individual but for other people around them. Alzheimer’s disease and related conditions are devastating for this reason.
The new U.S. research reveals an area that may be targeted for combating memory loss, especially among the elderly.
“Our results suggest that increasing the number of neurons that encode the same memory enables the memory to persist for longer,” said study co-author Carlos Lois, research professor of biology.
The researchers say that strong, stable memories depend on “teams” of neurons working together. This enables the brain to have redundancy and still have longer-lasting memories.
Conventional theories have suggested that the number of connections to an individual neuron is what makes a memory stable.
The study, which appeared in an August edition of Science, was led by postdoctoral researcher Walter Gonzalez.
How the Study Was Carried Out
Mouse models were used to arrive at this conclusion. A test measuring neural activity was developed and used whilst the animals tried to get familiar with and remember a place.
The scientists placed a mouse in an enclosure with unique symbols on the walls in different places. Water containing sugar was then situated at both ends of the 1.5-meter track.
Initially, the mice showed confusion when placed in the track. They would wander around until they came upon the sugar water, a favorite for mice.
When the mouse finally chanced upon the water, the researchers observed that single neurons were activated in it after it noticed a symbol on the wall. The animal was subsequently able to locate the water more easily as it became more familiar with the track.
Seeing the symbols on the wall activated more neurons in synchrony. In other words, recognition of the symbols made it easier to determine location.
It was observed that after 20 days away from the track, those mice that had created strong memories encoded by more neurons were able to remember the task quicker when they returned.
Aging and repetition effects
The researchers opine that their findings might explain why people tend to find it harder remembering information and events as they get older. As we grow older, fewer neurons are involved in the encoding of memory. Thus making it more likely for such memory to be lost.
Gonzalez and his team say that the repetition of an action makes it likely easier to remember later.
An analogy of friends occasionally re-telling a story was used to highlight how this can help to preserve and strengthen memory.
“For years, people have known that the more you practice an action, the better chance that you will remember it later,” Lois said. “We now think that this is likely, because the more you practice an action, the higher the number of neurons that are encoding the action.”
The Caltech researchers say future treatments that can help to increase the number of neurons encoding a memory may help to prevent memory loss.
- How memories form and fade | Cosmos (https://cosmosmagazine.com/biology/how-memories-form-and-fade)