Now a new study in Scientific Reports has tested the effect of naltrexone on musical enjoyment. Researchers at McGill University instructed a 15 students to choose two pieces of music that they loved—songs that make them feel chills—and bring them to the lab. There, the subjects received either naltrexone or a placebo. An hour later, the students listened to their chosen music, as well as two "neutral" songs that the scientists selected. As the music played, the students used a slider to indicate their current level of pleasure, while sensors measured electrical activity in their facial muscles. Before leaving, they took a survey about their reactions. A week later, the subjects went through the same thing, this time with the naltrexone group receiving placebos and vice versa.