"Swinging" when sick is actually to save life, and Nature reveals how the brain manipulates it all

When we are sick and feel unwell, we often become reluctant to eat, drink water, or move around
.
These behavioral changes are what scientists call "sickness behavior
.
"

These sick behaviors may make us feel uncomfortable, but in fact, when we or other animals are injured or infected by pathogens, these behaviors play an energy-saving effect – saving metabolic energy, leaving energy for the immune response, and therefore essential
for the survival of the individual.
Conversely, animals are forced to eat when they are sick and the risk of death increases
significantly.

But how did this extremely common act of sickness come about? How does the brain coordinate this desire not to eat and drink, but to lie flat? Recently, a study in the journal Nature uncovered the neural mechanism in mouse experiments: a special group of neurons in the brainstem regulates different sick behaviors, causing them not to want to eat, drink and move around
when they are sick.
This study directly links inflammation to the regulation of behavior by neural pathways, providing new insights
into the interaction of the immune system with the brain.

"Our understanding of the role the brain plays in infection is still in its early stages," said Jeffrey M.
Friedman, a professor at The Rockefeller University who led the study, "but based on these results, we now have the opportunity to explore: What does the brain look like when we are sick?" ”

In the latest study, the authors decided to find out the brain regions
behind the mice's sick behavior.
They exposed mice to lipopolysaccharides, which activate the immune system of mice and induce sick behavior
as a component of bacterial cell walls.