Brain cells tune in on success, monkey experiment finds
THURSDAY, July 30 (HealthDay News) -- It is often stated that people learn from their mistakes, but new research sugests people may figure out more from their successes than from their failures.
In experiments with monkeys, researchers at the Picower Institute for Learning and Memory at Massachusetts Institute of Technology (MIT) found that only correct actions resulted in changes in brain cells.
"We have shown that brain cells keep track of whether recent behaviors were successful or not," professor of neuroscience Earl K. Miller said in a news release from MIT. When a behavior was successful, brain cells became more finely tuned to what the monkey was learning. But failure produced little or no change in the brain, nor any improvement in behavior, the researchers found.
The study, published in the July 30 issue of Neuron, offers new insight into how the brain uses environmental feedback to change in response to experience.
In this study, monkeys were shown alternating images and were rewarded depending on whether they shifted their gaze to the right or the left. The monkeys used trial-and-error to determine the appropriate responses to the individual images.
"If the monkey just got a correct answer, a signal lingered in its brain that said, 'You did the right thing.' Right after a correct answer, neurons processed information more sharply and effectively, and the monkey was more likely to get the next answer correct as well," Miller said in the news release.
But after a monkey made an error "there was no improvement. In other words, only after successes, not failures, did brain processing and the monkeys' behavior improve."
The Society for Neuroscience has more about brain plasticity.
-- Robert Preidt
SOURCE: MIT, news release, July 30, 2009
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