Researchers performed functional magnetic resonance imaging (fMRI) of people's brains while they first tried to rapidly learn, then recall, a set of words as colorful pictures flashed in the background. Researchers then surprised the study subjects with a memory test about the pictures instead of the words.

Learning the pictures proved much more difficult when also trying to remembering a word, but became easier when a word was forgotten, a team from the Netherlands' University of Amsterdam and Duke University found.

According to the brain scans, the areas involved in learning the pictures were less activated when trying to recall the words at the same time -- a point the researchers noted in the current issue of PLoS Biology. The findings suggests that the recall process may suppress the parts of the brain involved in learning, the researchers said.

The scans also revealed a region in the left frontal part of the brain that was only active when the participants were successful at both learning and remembering. The activity seen here, though, was only noted in participants who showed little problem with the learning activity, suggesting that their brain activity wasn't affected by also trying to remember something at the same time.

The suggestion of a switchboard region of the brain is backed up by previous research showing that people who have damaged this area do not rapidly adapt to new situations well, but instead tend to abide by old rules.

More information

The U.S. National Library of Medicine has more about memory.