The brain is undoubtedly a complex and clever organ, but new research suggests it might be even more impressive than you originally thought. It turns out that the brain is particularly adept at discovering early-stage disease in other people.
The study was done at the Karolinska Institutet’s Department of Clinical Neuroscience. It found that not only can the brain detect disease before it breaks out, but humans also “have a tendency to act upon the signals by liking infected people less than healthy ones”.
Researchers injected harmless bacteria into subjects, meaning that their immune system responded and they developed classic symptoms of disease like tiredness and fever for a few hours.
Another group of people was exposed to the smells and images of these “diseased” subjects, alongside a group of perfectly healthy subjects. Their brain activity was measured in an MR scanner and they were asked to rate how much they liked the various people.
By looking at the photographs, they were asked who looked sick, who they considered attractive and who they would want to socialise with.
Principal investigator Professor Mats Olsson said: “Our study shows a significant difference in how people tend to prefer and be more willing to socialise with healthy people than those who are sick and whose immune system we artificially activated.”
It makes sense, it’s definitely preferable to hang out with people who aren’t diseased, but who knew the brain could detect this so early on?
Olsson said that this is biological confirmation of the argument that survival means avoiding infection as much as possible, but accepts that it doesn’t include people you have a close relationship with. It would be a bit much for parents to avoid their children when they catch a cold, wouldn’t it?
