"An unexpected event appears to clear out what you were thinking," said Adam Aron, a neuroscientist at the University of California, San Diego, who led the research.
"The radically new idea is that just as the brain's stopping mechanism is involved in stopping what we're doing with our bodies it might also be responsible for interrupting and flushing out our thoughts," Aron said.
"We are providing a neural mechanism by which that happens," he added. "The same stopping system that gives you that kind of jolt when you are getting out of the elevator, and someone else is in your way and you have to stop, that same stopping system is stopping your train of thought."...
"We've shown that unexpected, or surprising, events recruit the same brain system we use to actively stop our actions, which, in turn, appears to influence the degree to which such surprising events affect our ongoing trains of thought," said cognitive neurologist Jan Wessel, who worked on the study and who is now at the University of Iowa. (read the whole article?)