点击显示 收起
Aug. 2, 2006 -- When you're trying to learn or memorize something, try tossing some new information into the mix.
Doing so might help you learn and memorize, say two researchers from University College London.
Rehashing the same old information over and over is dullsville for the brain, compared to exploring new information, write Nico Bunzeck, MS, and Emrah Duzel, MD, PhD, in Neuron.
Behavioral psychology currently aims to boost patients' memory through repetition, as in studying for an exam, Duzel notes in a University College London news release.
But studying appears to be "more effective if you mix new facts in with the old," he says. "You actually learn better, even though your brain is also tied up with new information."
Familiar or New?
Bunzeck and Duzel conducted five tests, each of which included 14 healthy adults age 20-36 years.
Participants watched as pictures of men's faces or outdoor scenes flickered across a screen in a fraction of a second.
Most of the images were repeated several times. But sometimes, the researchers threw in oddball images that only appeared once.
The tests varied a bit, but they all focused on learning or memory and had the same basic question: "Have you seen this picture before?"
In some tests, participants also got their brains scanned by functional magnetic resonance imaging (fMRI).
Those brain scans focused on the midbrain's substantia nigra/ventral tegmental area (SN/VTA).
Oddball Advantage
Participants scored best on those tests when oddball images had been part of the series of pictures.
On the brain scans, the SN/VTA showed more activity when people saw the oddball images, compared to images they'd seen many times or just a few times before.
The SN/VTA makes a chemical called dopamine. Novelty may bring a reward in the form of more dopamine, the researchers suggest.
"We believe that experiencing novelty might, in itself, have an impact on our dopamine levels," Duzel says in the university news release.
"We hope that these findings will have an impact on behavioral treatments for patients with poor memory," he adds.
The study only included healthy young adults. So it's not clear if the results apply to people with cognitive problems.
Reaping Novelty's Rewards
It's not that the brain is fickle. But it may have a bit of the what-have-you-done-for-me-lately outlook.
The brain is always looking for a reward, and if it's learned that it won't get rewarded by very familiar information, it takes its chances with novelty, the researchers reason.
The study included some faces showing negative emotions, but that didn't change the results.
It would be interesting to repeat the test with some happy faces, says an editorial in Neuron.
"By beginning to trace links between novelty, reward, and memory, Bunzeck and Duzel have given us a good start toward understanding the motivation that drives explorers and scientists alike," write the editorialists.
They included Brian Knutson, PhD, of Stanford University's psychology department.
SOURCES: Bunzeck, N. Neuron, Aug. 3, 2006; vol 51: pp 369-379. News release, University College London. Knutson, B. Neuron, Aug. 3, 2006; vol 51: pp 280-282. News release, Cell Press.