(ISNS) -- A team of mind readers can now pinpoint exactly when a
rat feels uncertain about its choices, simply by measuring its
brain activity. Doubt, they've discovered, creeps into the mind
slowly. It starts with a few nerve cells near the front of the
brain that get themselves into a tizzy. More and more cells join
in, until a line is crossed and the mental maelstrom shakes up
established patterns of brain activity -- allowing rats, and
possibly humans as well, to question their old beliefs about the
world and explore new options, researchers report in the October
5 issue of the journal Science. "When your environment changes,
you want to be able to reevaluate the world," said Alla Karpova,
a neuroscientist at the Howard Hughes Medical Institute’s
Janelia Farm campus in Ashburn, Va. "We have seen an abrupt
change in neural activity at a moment when an animal seems to
abandon a previously held belief." Karpova studies the medial
prefrontal cortex, a brain region that's thought to guide
decisions by weighing