Neuroscientist John Cryan investigates how the gut microbiome affects the mammalian brain. He is Chair of the Department of Anatomy and Neuroscience and Principal Investigator in the Alimentary Pharmabiotic Center at University College of Cork (Ireland). His research has far-reaching public health implications, from how we view Caesarean sections, to how the microbiome influences brain development, to the impact of probiotics on mood. John’s work shows that the term “gut feeling” might actually make neurobiological sense.