Those Infectious Ideas.

“When we learn something new, our neurons tear down old connections and build new ones. In the process they cast off lots of molecules. To the immune system, this waste may look like an infection or some other kind of trouble, resulting in inflammation and the release of harsh compounds that normally fight viruses but can also interfere with the brain and its function.”

A novel path of brain research suggests our immune system may play a key role in determining intelligence. “The same T cells that protect the brain from inflammation also work to keep us sharp; and in what appears to be a feedback loop, the mere act of learning reinforces the effect.”