By monitoring activity levels in the human brain's prefrontal cortex, the researchers demonstrate for the first time that people who have more activity in the left side of this area also have a stronger immune response against disease. The findings, soon to be published in the online edition of the journal Proceedings of the National Academy of Sciences, pinpoint one of the mechanisms underlying the link between mental and physical well-being.
Numerous scientific studies show that keeping a positive attitude can keep a person healthy, says Richard Davidson, a UW-Madison neuroscientist and senior author of the paper. But he adds that the reasons why this connection exists are poorly understood.
By turning to the brain - an organ that sends signals that guide emotional response - Davidson and his group have identified one possible explanation: activity in the prefrontal cortex, a region of the brain long associated with affective style, or how a person responds emotionally to an event.
"Emotions play an important role in modulating bodily systems that influence our health," says Davidson. "We turned to the brain to understand the mechanisms by which the mind influences the body."
While earlier studies have linked emotional and physical health, as well as brain activity and affective style, Davidson says none have established a direct link between brain activity and immune function.
The latest study by the UW-Madison group demonstrates this connection.
For the study, the researchers worked with 52 individuals between the ages of 57 and 60 who were recruited from the Wisconsin Longitudinal Study - a long-term study of more than 10,000 people who graduated from Wisconsin high schools in 1957. Sp
Contact: Richard Davidson
University of Wisconsin-Madison