- Sad, fearful and angry thoughts can weaken the body's
protective immune system and make it more vulnerable to disease, according
to a brain scanner study published today.
- Researchers have long known that a link exists between
psychological states and immune response, notably between depression and
vulnerability to a wide range of diseases. However, the mechanism behind
this link is poorly understood.
- Now a direct connection between brain activity and immune
function has been demonstrated in an experiment by a team at the University
of Wisconsin, Madison.
- A paper by the team in the journal Proceedings of the
National Academy of Sciences today pinpoints one of the mechanisms underlying
the link, revealing it to lie in the brain's prefrontal cortex. This region
has long been associated with emotions, as well as planning and awareness.
- Dr Richard Davidson and colleagues asked 52 female subjects
to recount either the best or worst times of their lives by thinking and
then writing about these subjects.
- As the subjects wrote, the researchers measured physiological
indicators of emotional reactions and used electroencephalograph recordings
to measure electrical activity in the brain.
- Each participant was then given a flu shot, and flu antibody
levels were measured at intervals in the six months afterwards. Those subjects
who exhibited more intense negative emotions while recounting negative
experiences produced a weaker response to the vaccine, suggesting they
had impaired immunity.
- While earlier studies had linked emotional and physical
health, as well as brain activity and emotion, Dr Davidson said none had
established a direct link between brain activity and immune function.
- © Copyright of Telegraph Group Limited 2003.