Using functional MRI to watch human brains in action, the researchers showed that emotional stimuli and "attentional functions" like driving move in parallel streams through the brain before finally meeting up in a specific part of the brain's prefrontal cortex.
The results, published in the August 20 issue of The Proceedings of the National Academy of Sciences (PNAS), help explain why a person who suddenly feels a pang of emotion is especially likely to lose focus. They also may lead to new avenues of research for treating depression, attention-deficit disorder, post-traumatic stress syndrome and other disorders.
"We've known for a long time that some people are more easily distracted and that emotions can play a big part in this," said Kevin S. LaBar, assistant professor at Duke's Center for Cognitive Neuroscience and an author of the study. "Our study shows that two streams of processing take place in the brain, with attentional tasks and emotions moving in parallel before finally coming together." The two streams are integrated in a region of the brain called the anterior cingulate, which is located between the right and left halves of the brain's frontal portion and is involved in a wide range of thought processes and emotional responses.
LaBar and his colleagues used functional MRI devices to study the brains of neurologically healthy subjects who tried to pay attention to specific visual targets on a screen. The test subjects were distracted in various ways, sometimes by images that were likely to evoke an emotional response. The results confirmed previous findings that emotional stimuli are more likely to cause a person to lose focus. However, they also shed light on the
Contact: David Jarmul