NPR's "Hidden Brain" program took a look at the science of compassion in a program featuring Professor of Psychology Scott Plous and the "Day of Compassion" exercise that he leads in his social psychology courses at Wesleyan and in his Social Psychology MOOC on Coursera. "Scott radiates kindness," said host and science correspondent Shankar Vedantam in introducing Plous. More than 250,000 students from around the world signed up for the first run of Plous' MOOC. The course capstone was the Day of Compassion exercise in which "students had to spend one day being deliberately kind and generous toward others. Scott asked them to notice how these actions…