John Sutter plays some sounds and asks his listeners to tell him how they feel. He finds that these sounds can trigger emotions, similar to Pavlov's famous experiment with dogs way back in 1897. This associative learning where we're associating a cause with an effect is central to how animals, how we learn and how we deal with the world.
The response to the death of the 29-year-old has differed from that of previous cases of police killings; we ask what the tragedy indicates about how America deals with police violence. Our correspondent says a lawmaker’s murder in Afghanistan highlights the misery of women under the Taliban. And why a decades-old model of animal and human learning is under fire.
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