the wrong people and doing the wrong stuff and i wouldn t woodruff: margaret warner explores the dramatic results of a new study showing paralyzed patients moving their robotic arms just by thinking. brown: we update the trial of john edwards, as the defense rests its case without calling the former presidential candidate or his mistress to testify. woodruff: and we remember mexican writer carlos fuentes, whose prolific literary career spanned more than five decades. that s all ahead on tonight s newshour. major funding for the pbs newshour has been provided by: and with the ongoing support of these institutions and foundations. and. this program was made possible by the corporation for public broadcasting. and by contributions to your pbs station from viewers like you. thank you. woodruff: the confrontation over raising the national debt ceiling consumed washington for much of 2011. now, the issue has re-emerged. it was raised at a white house meeting today, and sp