New Findings Suggest That Sleep Plays A Crucial Role In Flagging And Storing Important Memories
Benedict Carey
Benedict Carey
The task looks as simple as a “Sesame Street” exercise. Study pairs of Easter eggs on a computer screen and memorise how the computer has arranged them: the aqua egg over the rainbow one, the paisley over the coral one — and there are just six eggs in all.
Most people can study these pairs for about 20 minutes and ace a test on them, even a day later. But they’re much less accurate in choosing between two eggs that have not been directly compared: Aqua trumped rainbow but does that mean it trumps paisley? It’s hazy. It’s hazy, that is, until you sleep on it.
In a study published in May, researchers at Harvard and McGill Universities reported that participants who slept after playing this game scored significantly higher on a retest than those who did not sleep. While asleep they apparently figured out what they didn’t while awake: the structure of the simple hierarchy that linked the pairs, paisley over aqua over rainbow, and so on.
“We think what’s happening during sleep is that you open the aperture of memory and are able to see this bigger picture,” said study author, Matthew Walker, a neuroscientist who is now at the University of California, Berkeley. He added that many such insights occurred “only when you enter this wonder-world of sleep.”
Scientists have been trying to determine why people need sleep for more than 100 years. They have not learned much more than what every new parent quickly finds out: sleep loss makes you more reckless, more emotionally fragile, less able to concentrate and almost certainly more vulnerable to infection. They know, too, that some people get by on as few as three hours a night, even less, and that there are hearty souls who have stayed up for more than week without significant health problems.
Now, a small group of neuroscientists is arguing that at least one vital function of sleep is bound up with learning and memory. A cascade of new findings, in animals and humans, suggest that sleep plays a critical role in flagging and storing important memories, both intellectual and physical, and perhaps in seeing subtle connections that were invisible during waking — a new way to solve a math or Easter egg problem, even an unseen pattern causing stress in a marriage.
The theory is controversial, and some scientists insist that it’s still far from clear whether the sleeping brain can do anything with memories that the waking brain doesn’t also do, in moments of quiet contemplation.
Yet the new research underscores a vast transformation in the way scientists have come to understand the sleeping brain. Once seen as a blank screen, a metaphor for death, it has emerged as an active, purposeful machine, a secretive intelligence that comes out at night to play — and to work — during periods of dreaming and during the netherworld chasms known as deep sleep.
“To do science you have to have an idea, and for years no one had one; they saw sleep as nothing but an annihilation of consciousness,” said Dr J Allan Hobson, a psychiatry professor at Harvard. “Now we know different, and we’ve got some very good ideas about what’s going on.” NYT NEWS SERVICE
Most people can study these pairs for about 20 minutes and ace a test on them, even a day later. But they’re much less accurate in choosing between two eggs that have not been directly compared: Aqua trumped rainbow but does that mean it trumps paisley? It’s hazy. It’s hazy, that is, until you sleep on it.
In a study published in May, researchers at Harvard and McGill Universities reported that participants who slept after playing this game scored significantly higher on a retest than those who did not sleep. While asleep they apparently figured out what they didn’t while awake: the structure of the simple hierarchy that linked the pairs, paisley over aqua over rainbow, and so on.
“We think what’s happening during sleep is that you open the aperture of memory and are able to see this bigger picture,” said study author, Matthew Walker, a neuroscientist who is now at the University of California, Berkeley. He added that many such insights occurred “only when you enter this wonder-world of sleep.”
Scientists have been trying to determine why people need sleep for more than 100 years. They have not learned much more than what every new parent quickly finds out: sleep loss makes you more reckless, more emotionally fragile, less able to concentrate and almost certainly more vulnerable to infection. They know, too, that some people get by on as few as three hours a night, even less, and that there are hearty souls who have stayed up for more than week without significant health problems.
Now, a small group of neuroscientists is arguing that at least one vital function of sleep is bound up with learning and memory. A cascade of new findings, in animals and humans, suggest that sleep plays a critical role in flagging and storing important memories, both intellectual and physical, and perhaps in seeing subtle connections that were invisible during waking — a new way to solve a math or Easter egg problem, even an unseen pattern causing stress in a marriage.
The theory is controversial, and some scientists insist that it’s still far from clear whether the sleeping brain can do anything with memories that the waking brain doesn’t also do, in moments of quiet contemplation.
Yet the new research underscores a vast transformation in the way scientists have come to understand the sleeping brain. Once seen as a blank screen, a metaphor for death, it has emerged as an active, purposeful machine, a secretive intelligence that comes out at night to play — and to work — during periods of dreaming and during the netherworld chasms known as deep sleep.
“To do science you have to have an idea, and for years no one had one; they saw sleep as nothing but an annihilation of consciousness,” said Dr J Allan Hobson, a psychiatry professor at Harvard. “Now we know different, and we’ve got some very good ideas about what’s going on.” NYT NEWS SERVICE
Some neuroscientists say that at least one vital function of sleep is tied to learning and memorycourtesy:TOI
