What researchers did was teach the participant a new series of symbols (not our common Arabic numerals) that represented numbers. While their brains were being shocked, they tested their ability to organize the numbers. People who had received the electricity were better than people who weren't.
While there's no safe, practical use for these findings at the moment, scientists are excited at the prospect of being able to improve people's abilities in the future. And while people will still need to put an effort behind these skills, they can still help people. In the meantime, please don't lick batteries before your math tests.