Dr. Bailey has nearly 20 years of experience studying bidirectional interactions between host physiology and the microbes that naturally reside within the gastrointestinal tract (i.e., the gut microbiota). Dr. Bailey’s studies were among the first to show that stressful situations can lead to changes in the composition of the gut microbiota and his current studies are now focused on the impact that changes to gut microbiota composition have on the functioning of the immune system and on nervous system activity.