Physicians have long observed a mystifying phenomenon: After a bout of infection or an autoimmune disease flare-up, some people experience prolonged mood swings, emotional dysregulation, and changes in behavior. But the precise connection between inflammation, mood, and behavior has remained elusive.
Now, two new studies from Harvard Medical School and Massachusetts Institute of Technology, published April 7 in Cell, detail the steps of an intricate brain-immune crosstalk that accounts for this long-known but poorly understood observation.
The work, conducted in mice and funded in part by the National Institutes of Health, pinpoints the molecular roots of the phenomenon and shows how immune molecules called cytokines influence brain activity.
Scientists already knew that cytokines affect emotions…