The brain parasite "Toxoplasma gondii" causes extroversion. The parasite's life cycle usually runs through rats and mice, where it releases hormones to reduce their fear of cats eating the parasitic mice. The parasite then multiplies in the cats via the excrement. And since the parasite also infects humans, the hormone release there leads to extroversion. The estimated number of people affected by parasites is 22,5% of all Americans over the age of 12. So you can now scientifically correctly claim the following: A very large proportion of successful career people, business clowns and tie wearers are actually just sick ass fiddles. Very interesting!
I guess - and even halfway seriously, you can easily solve a lot of the problems in the world like wars, business fools, footballers, politicians in general and the conservative part of them in particular by exterminating this one parasite. They will then all become sensible and we will have more world peace, hippies, artists and creatives, scientists in general and space and biotech in particular. Snip from Scientific American magazine:
Feeling sociable or reckless? You might have toxoplasmosis, an infection caused by the microscopic parasite Toxoplasma gondii, which the CDC estimates has infected about 22.5 percent of Americans older than 12 years old. Researchers tested participants for T. gondii infection and had them complete a personality questionnaire. They found that both men and women infected with T. gondii were more extroverted and less conscientious than the infection-free participants. These changes are thought to result from the parasite's influence on brain chemicals, the scientists write in the May / June issue of the European Journal of Personality.
“Toxoplasma manipulates the behavior of its animal host by increasing the concentration of dopamine and by changing levels of certain hormones,” says study author Jaroslav Flegr of Charles University in Prague, Czech Republic. Although humans can carry the parasite, its life cycle must play out in cats and rodents. Infected mice and rats lose their fear of cats, increasing the chance they will be eaten, so that the parasite can then reproduce in a cat's body and spread through its feces.
In humans, T. gondii's effects are more subtle; the infected population has a slightly higher rate of traffic accidents, studies have shown, and people with schizophrenia have higher rates of infection — but until recent years, the parasite was not thought to affect most people's daily lives. In the new study, a pattern appeared in infected men: the longer they had been infected, the less conscientious they were.