New Connections Found Between Spleen and Brain

In the past, scientists discounted the importance of the spleen, a five-ounce organ located in the upper left abdomen. Now, there's an increasing understanding of the spleen's importance as a part of the immune system, filtering blood and removing old blood cells.

Writing this week in the Proceedings of the National Academy of Sciences, a team of investigators reports that the spleen and the brain may be more closely connected than previously thought.

The splenic nerve, the researchers find, can communicate with the vagus nerve, which then serves as a conduit of information from the brain to the immune system. Manipulating the central nervous system may allow medical professionals to stimulate activity within the spleen, producing compounds needed to fight infection.

Scientist Mauricio Rosas-Ballina, one of the researchers on the project, talks with host Ira Flatow about the findings.