A long-buried, oft-derided theory is gaining traction in the medical world: cats are harboring a parasite that can manipulate human behaviour and personality, sometimes to fatal ends. According to The Atlantic’s Kathleen McAuliffe, the work of Jaroslav Flegr is finding support from others in his field. Flegr theorizes that a parasite called Toxoplasma gondii, which is found in cat feces, can infect the human brain in a variety of ways.
The effects of T. gondii range from seemingly benign — it makes men more introverted and women more extroverted — to deadly, as it may contribute to schizophrenia or to slower reaction times that lead to car crashes.
In Flegr’s estimation, the parasite’s kill count can add up to at “least a million people a year.”
Because the parasite can only reproduce inside of cats, it’s in T. gondii’s best interest to manipulate human beings so it can jump back to another cat. Flegr himself said he didn’t fear Communism or get out of the way of oncoming traffic because he may have subconsciously wanted to die.
Though past reports on T. gondii have made this connection, there was little support for the theory that the virus could have an effect on people. But more and more big names in neuroscience, like Stanford’s Robert Sapolsky, are throwing support behind the research. And two separate Turkish studies confirmed Flegr’s findings on T. gondii’s relationship to traffic accidents.
Effects of the parasite are subtle, making it very difficult to detect on your own. But if you’re a man and you rank the smell of cat urine much more favourably than your friend, you might want to get tested (the effect is the opposite for women).
Now see: Cats Using Computers >
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