Study shows changes in two regions right before an error is made
WEDNESDAY, April 23 (HealthDay News) -- Sometimes while performing repetitive tasks, people make mistakes.
Now new research has uncovered the existence of a pattern of activity across two regions of the brain that occur up to 30 seconds before some, but not all, errors are made.
The finding counters the popular view that human error is simply a function of instantaneous brain blips, while also suggesting that some mistakes are neurologically predictable. And in theory, the mapping of such brain sequences could ultimately lead to the development of brain-monitoring techniques intended to boost individual safety by warning of imminent mistakes.
"It's not that this pattern of brain activity always happens before an error," said study author Dr. Tom Eichele, of the department of biological and medical psychology at the University of Bergen, in Bergen, Norway. "But we did see that when you have this pattern, the likelihood of making an error is 50 percent greater than otherwise."
Eichele and his team reported the findings in this week's issue of the Proceedings of the National Academy of Sciences.
The authors set out to observe pre-error brain activity with the aid of functional MRIs. This scanning technology allows physicians to take snapshots of changes in brain blood flow that accompany any increase or decrease in activity throughout different regions of the brain.
Thirteen healthy men and women between the ages of 22 and 29 participated in the study.
All were asked to engage in a standard visual test known as the "flanker task." This visual exercise required the participants to quickly view repeated images of a central pointed arrow surrounded by peripheral arrows pointing either in the same director or in the opposite direction of the center arrow.
The participants had to repeatedly identify -- as fast as possible -- whether or not each successive picture displayed central and peripheral arrows pointing together or inversely. The researchers noted that typically when arrows do not all point in the same direction response time slows and becomes less accurate.
About 400 rounds of the flanker task exercise were conducted, and an analysis of fMRI brain scans taken during the test revealed that prior to the commission of an error, the brain launched two simultaneous activities in two distinct brain regions.
The first site of activity was the frontal lobe of the brain, which controls cognition and working memory. A boost in this region's activity usually occurs to optimize a person's ability to maintain and complete tasks. However, before making of a mistake, this area was found to gradually ratchet down its activity.
At the same time as frontal lobe action decreased, activity actually increased in a second grouping of several regions in the back of the brain, known as the "Default Mode Network" (DMN). In this particular region, an increase in activity is usually linked to a resting or relaxed state of mind.
The twin brain actions were found to initiate at least six seconds before a mistake took place, and as early as 30 seconds prior to an error.
Though Eichele and his team had tallied an 8 percent to 9 percent overall error rate in the flanker test, they stressed that not all the committed errors were linked to such synchronized brain patterns. However, when the up/down regional sequencing unfolded, it appeared to raise the risk for making an error by 50 percent.
"This pattern is not the sole causal factor for mistakes," said Eichele. "But it's a contributing factor, that might relate to the brain being tired and needing a break. For now, we're continuing our research. But you can already imagine that some day we might be able to measure this phenomenon in people as they go along performing real-world tasks, using mobile and wireless EEG devices, to measure the brain's electrical activity and predict errors before they happen.
"But that's way down the road," he added. "Five, ten, fifteen years down the road."
H. Elliot Albers, director of the Center for Behavioral Neuroscience at Georgia State University in Atlanta, described the findings as "very interesting."
"I think it offers possibilities for the future," he said, "in terms of understanding how the brain either recognizes errors it's about to make or how it's going to cause mistakes in advance, if in fact the patterns are causative. And, yes, understanding all of this very well might lead to safety applications in the future. But, I agree, that's way down the road."
For more on how the brain works, visit the National Institute of Neurological Disorders and Stroke.
SOURCES: Tom Eichele, M.D., Ph.D., department of biological and medical psychology, University of Bergen, Bergen, Norway; H. Elliot Albers, director, Center for Behavioral Neuroscience, Georgia State University, Atlanta; April 21-25, 2008, Proceedings of the National Academy of Sciences
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