Adolescents act much like adults in many situations, but often act more impulsively under stress. One explanation, a University of Pittsburgh neuroscientist says, may lie in the brain's working memory.

Working memory is where the brain stores information used to make immediate calculations and it develops and changes from childhood to adulthood.

Pitt's Beatriz Luna reported last week at the Society for Neuroscience meeting in San Diego on brain-imaging studies of working memory that she performed using pre-adolescent, adolescent and adult volunteers. She found that as people age, they incorporate additional regions of the brain into their working memory.

A region used by adults, the medial temporal lobe, may make the difference, she suggested, enabling adults to keep information in working memory long enough that they can make rational decisions under pressure.