Close your eyes and just listen. Even if you aren’t actively thinking about the noises happening around you, your brain is constantly processing sound. That’s because, unlike your eyes, your ears never close. In fact, Northwestern neurobiology professor Nina Kraus, says listening is one of the hardest tasks we ask our brains to do. On today’s episode, Kraus explains how the sounds we’re surrounded by everyday – like a noisy leaf blower or the soothing sound of music – really matter and can impact our physical and mental health. Plus, she shares tips for building a healthy “sonic world.” To learn more about how CNN protects listener privacy, visit cnn.com/privacy