Tracing Molecules That Make the Brain-Body Connection

Researchers once considered the body's network of immune defenses a system unto itself, but they have learned over the past 15 years that it is intimately intertwined with the nervous and endocrine systems. Recently, researchers have begun unraveling the molecular links between these systems, which include the interleukins and hormones such as corticosteroids. And as these connections come to light, they are helping explain some previously mysterious correlations between mental and hormonal states and the immune system.