What happens in your brain when you get lost or forget something? Johns Hopkins University cognitive psychologist Amy Shelton believes she can find the answer. Shelton is testing human spatial recognition. Study subjects learn and recall their way around a virtual maze while an MRI scans their brains. Find out more in this Science Nation video.
Credit: Science Nation, National Science Foundation
Research tells us that children in general need to get more sleep, but recent findings indicate that kids from lower-income families suffer more from sleep deprivation than middle- and upper-income kids. Auburn University psychologist Mona El-Sheikh wants to know why. With support from NSF, she and her team are studying children's sleeping patterns and how lack of sleep correlates with the stress factors in their lives and with their ability to learn. Find out more in this Science Nation video.
Credit: Science Nation, National Science Foundation
For the first time, scientists at the University of Southern California have unlocked a mechanism behind the way short- and long-term motor memory work together and compete against one another. The research could potentially pave the way to more effective rehabilitation for stroke patients. Hear more in this Discovery Files podcast.
Credit: NSF/Karson Productions
The Division of Behavioral and Cognitive Sciences (BCS) of the Directorate for Social, Behavioral and Economic Sciences supports research to develop and advance scientific knowledge on human cognition, language, social behavior and culture, as well as research on the interactions between human societies and the physical environment.
Ken Paller's Lab focuses on understanding human memory and related cognitive functions--and their implementation in the brain. Researchers use multiple techniques for measuring brain activity as part of a cognitive neuroscience approach that respects both the complexity of cognition as well as the intricate organization of the brain.
One of the biggest puzzles in neuroscience is how our brains encode thoughts, such as perceptions and memories, at the cellular level. Some evidence suggests that ensembles of neurons represent each unique piece of information, but no one knows just what these ensembles look like, or how they form.
Researchers at the University of California, Los Angeles, have for the first time, measured the activity during sleep of a brain region known to be involved in learning, memory and Alzheimer's disease, and what they discovered counters conventional theories about sleep-time memory consolidation.
Scientists have found that sleep helps consolidate memories, fixing them in the brain so people can retrieve them later. Authors of an article in the journal Current Directions in Psychological Science report that research is showing that sleep also seems to reorganize memories, picking out the emotional details and reconfiguring the memories to help people produce new and creative ideas.
January 14, 2013
The Connection Between Memory and Sleep
Researchers found information can be better retained with reinforcing stimuli delivered during sleep
When you're studying for an exam, is there something you can do while you sleep to retain the information better?
"The question is, 'What determines which information is going to be kept and which information is lost?'" says neuroscientist Ken Paller.
With support from the National Science Foundation (NSF), Paller and his team at Northwestern University are studying the connection between memory and sleep, and the possibilities of boosting memory storage while you snooze.
"We think many stages of sleep are important for memory. However, a lot of the evidence has shown that slow-wave sleep is particularly important for some types of memory," explains Paller.
Slow-wave sleep is often referred to as "deep sleep," and consists of stages 3 and 4 of non-rapid-eye-movement sleep.
Paller's lab group members demonstrated for Science Nation two of the tests they run on study participants. In the first experiment, the subjects learned two pieces of music in a format similar to the game Guitar Hero. During a short nap following learning, just one of the learned tunes was played softly several times, to selectively reinforce the memory for playing that tune without any reinforcement for the other tune. Paller wanted to know whether the test subjects could more accurately produce the tune played during sleep.
In the second exercise, the subjects were asked to memorize the location of 50 objects on a computer screen. The presentation of each object was coupled with a unique sound. During the post-learning nap, memory for the location of 25 objects was reinforced by the play-back of only 25 of the sounds. In this case, Paller wanted to know whether the subjects could remember object locations better if the associated sounds were played during sleep.
Researchers recorded electrical activity generated in the brain using EEG electrodes attached to the scalp. They thus determined whether the subjects entered "deep sleep," and only those who did participated in the reinforcement experiments. In both experiments, participants did a better job remembering what was reinforced while they slept, compared to what was not reinforced.
"We think that memory processing happens during sleep every night," says Paller. "We're at the beginning of finding out what types of memory can be reinforced, how large reinforcement effects can be, and what sorts of stimuli can be used to reactivate memories so that they can be better consolidated."
Paller's goal is to better understand the fundamental brain mechanisms responsible for memory. And that, in turn, may help people with memory problems, including those who find themselves more forgetful as they age.
"We experience progressively less slow-wave sleep as we age. Of course, many brain mechanisms come into play to allow us to remember, including some processing that transpires during sleep. So, there's a lot to figure out about how memory works, but I think it's fair to say that the person you are when you're awake is partly a function of what your brain does when you're asleep," explains Paller. He says these reactivation techniques could turn out to be valuable for enhancing what people have learned.
"What is beautiful about this set of experiments is that Dr. Paller identified 'deep sleep' as a critical time window during which memory for specific experiences can be selectively enhanced by the method of reactivation without conscious effort," says Akaysha Tang, director of the cognitive neuroscience program in the NSF Directorate for Social, Behavioral and Economic Sciences.
"Normally, conscious rehearsal of memorized material is needed if one wants to remember something better or retain it for longer, and one has to find time to review or rehearse," continues Tang. "Dr. Paller and the members of his lab group showed that such selective enhancement could be achieved without conscious effort and without demanding more of one's waking hours. So, instead of pulling that all-nighter to memorize the material, in the future, it may be possible to consolidate the memory by sleeping with a scientifically programmed lullaby!"
Any opinions, findings, conclusions or recommendations presented in this material are only those of the presenter grantee/researcher, author, or agency employee; and do not necessarily reflect the views of the National Science Foundation.
