A brain parasite that amazingly alleviates rats' innate fear of cat urine does not affect other kinds of fear, a new Stanford University study suggests. Normally, the smell of cat piss scares the hell out of rats. Yet when the rodents are infected with the parasitic germ Toxoplasma gondi, they don't seem to mind the urine. Even more unusual though is that they react normally to other scary or unfamiliar things like open spaces and odd smells. From LiveScience:
This discovery could shed light "on how fear is generated in the first place" and how people can potentially better manage phobias, researcher Ajai Vyas, a Stanford University neuroscientist, told LiveScience…
Although the disease (that the parasite) causes in humans is rarely dangerous, it is the reason that pregnant women are sometimes told to avoid cat litter boxes (toxoplasmosis is risky for infants and others with compromised immune systems). Some scientists have suspected it might be linked to mental disorders such as schizophrenia and even neuroticism.
In 2000, scientists revealed T. gondii could modify the brains of rats to make them attracted to cat urine instead of afraid of it. Researchers suspect the germ does so to make it easier for it to jump into cats to begin the sexual part of its life cycle.
Link (via Fortean Times)
