Researchers discover key to the reduction of forgetting

by James Devitt

A team of neuroscientists has found a key to the reduction of forgetting. Their findings, which appeared in the journal Neuron, show that the better the coordination between two regions of the brain, the less likely we are to forget newly obtained information.

The study was conducted at NYU by Lila Davachi, an associate professor in the Department of Psychology and Center for Neural Science, and Kaia Vilberg, now a postdoctoral researcher at the University of Texas.

"When memories are supported by greater coordination between different parts of the brain, it's a sign that they are going to last longer," explains Davachi.

It is commonly understood that the key to memory consolidation—the cementing of an experience or information in our brain—is signaling from the brain's hippocampus across different cortical areas. Moreover, it has been hypothesized, but never proven, that the greater the distribution of signaling, the stronger the memory takes hold in our brain.

In the Neuron study, Davachi and Vilberg sought to determine if there was scientific support for this theory. To do so, they examined how memories are formed at their earliest stages through a series of experiments over a three-day period.

On day one of the study, the researchers aimed to encode, or create, among the study's subjects. They showed participants a series of images—objects and outdoor scenes, both of which were paired with words. Subjects were asked to form an association between the word and image presented on the screen.

On day two, the subjects returned to the lab and completed another round of encoding tasks using new sets of visuals and words. This allowed the researchers to compare two types of memory: the more consolidated, long duration memories encoded on day one, with the less consolidated, short duration memories encoded on day two.

After a short break, participants were placed in an MRI machine—in order to monitor neural activity—and viewed the same visual-word pairings they saw on days one and two as well as a new round of visuals paired with words. They then completed a memory test of approximately half of the visual-word pairings they'd seen thus far. On day three, they returned to the lab for a on the remaining visuals.

By testing over multiple days, the researchers were able to isolate memories that declined or were preserved over time and, with it, better understand the neurological factors that contribute to memory preservation.

Their results showed that memories (i.e., the visual-word associations) that were not forgotten were associated with greater coordination between the hippocampus and left perirhinal cortex (LPRC)—two parts of the brain previously linked with memory formation. By contrast, there was notably less connectivity between these regions for visual-word associations that the study's subjects tended to forget.

Moreover, the researchers found that the coordinated between the and the LPRC—but not overall activity in these regions—was related to memory strengthening, arguing for the network's contribution to memory longevity.

"These findings show the brain strengthens memories by distributing them across networks," explains Davachi. "However, this process takes time. Day-old memories show greater coordinated brain activity compared to recent ones. This suggests that coordinated brain activity increases with time after a is initially formed."

add to favorites email to friend print save as pdf

Related Stories

A mind at rest strengthens memories, researchers find

Jan 27, 2010

Our memories are strengthened during periods of rest while we are awake, researchers at New York University have found. The findings, which appear in the latest issue of the journal Neuron, expand our understanding of how ...

Recurring memory traces boost long-lasting memories

Dec 05, 2013

While the human brain is in a resting state, patterns of neuronal activity which are associated to specific memories may spontaneously reappear. Such recurrences contribute to memory consolidation—i.e. ...

Recommended for you

Tackling neurotransmission precision

7 hours ago

Behind all motor, sensory and memory functions, calcium ions are in the brain, making those functions possible. Yet neuroscientists do not entirely understand how fast calcium ions reach their targets inside ...

What makes kids generous? Neuroscience has some answers

7 hours ago

It's no secret that people are judgmental, and young children are no exception. When children witness "good" or "bad" behavior, their brains show an immediate emotional response. But, according to a study ...

User comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.