News From NPR

Scientists are beginning to understand how people tune in to a single voice in a crowded, noisy room.

This ability, known as the "cocktail party effect," appears to rely on areas of the brain that have completely filtered out unwanted sounds, researchers report in the journal Neuron. So when a person decides to focus on a particular speaker, other speakers "have no representation in those [brain] areas," says Elana Zion Golumbic of Columbia University.

Attorney General Eric Holder appeared before the Senate Judiciary Committee on Wednesday to answer questions on everything from gun control to the Department of Justice's failure to prosecute Wall Street. But he was also asked about an issue proponents of marijuana legalization have been following closely: what the DOJ plans to do about Colorado and Washington state, which have defied federal law by legalizing recreational use of the drug.

Arkansas has approved a law banning most abortions after 12 weeks of gestation, as both houses of the state's legislature vote to override a veto by Democratic Gov. Mike Beebe. The Republican-backed Human Heartbeat Protection Act will become the nation's most restrictive law.

In vetoing the Senate version of the bill Monday, Beebe said that it "would impose a ban on a woman's right to choose an elective, nontherapeutic abortion well before viability."

Sen. Rand Paul has been talking for hours on the floor of the Senate today in an effort to delay the nomination of John Brennan for CIA chief.

More than three decades ago, Soviet soldier Bakhretdin Khakimov went missing in Afghanistan after he was wounded in battle with Afghan mujahedeen forces.

His whereabouts remained unknown until two weeks ago, when he was tracked down by a team from the Warriors-Internationalists Affairs Committee, a Moscow-based nonprofit that looks for Soviet MIAs in Afghanistan.