Mind Control Parasites and Human Behavior

A while back someone recommended Vinge’s “Rainbow’s End”. One of the plot elements is, more or less, a mind-control virus.

It turns out that someone — well, something — else had the same idea. Researchers have figured out that Toxoplasma gondii parasites are able to affect the behavior of the host so as to act in the interests of the parasite. In this case, the parasite causes infected rats to deliberately put themselves in danger, increasing the odds that they’ll be eaten by a cat. Why? Because the body of a cat is the only place T. gondii can have sex. And even parasites wanna get laid.

Okay, interesting. What does that have to do with security?

Depending on where you live in the world, 25-95% of the people are infected by T. gondii. It turns out that these parasites are able to affect people in similar ways as they do rats.

People with T. gondii infections are marked by a few characteristics, compared with those that aren’t: – slower reflexes
– reduced altruism
– a reduced hunger for new stimuli
– increased extroversion
– reduced conscientiousness
– reduced diplomatic skill
– increased belief that people can be controlled by hypnotism or “other means”
– and, most importantly, when attacked a tendency tend to stop fighting at a critical point because “something in their subconscious betrays them”

Now if only someone would come up with an easy way to diagnose and cure toxoplasmosis… we need one of those body scanner things from Star Trek.

Only tangentially related, rather disgusting, and yet still good enough to link to: http://fray.com/drugs/worm/ http://www.metafilter.com/115998/Tapeworms-Living-Inside-Peoples-Brains



“Tachyzoites and other invading T. gondii can bring a human several weeks of low-grade, achy, flulike discomfort […]

A healthy human immune system doesn’t necessarily eliminate the banana-clone army but typically drives it to retreat. Under full attack, the parasite wraps itself in tiny bomb-shelter cysts, mostly in the muscle and brain tissues of its host. (Not many parasites can safecrack their way into the well-protected brain, but once there, they enjoy a respite from the full strength of the host immune system.)

Inside these cysts, T. gondii keep the cloning, and thus the infection, going in slow motion for years, ready to jump to any new host if given a chance. These cysts are the T. gondii form accused of mind control and other mind-jacking stunts in affected humans.”


“Cloninger’s TCI showed that infected subjects, both men and women, have decreased scores on factor NS – novelty seeking, i.e. a lower tendency to search for new stimuli (Flegr et al., 2003; Skallová et al., 2005).[…]

Some studies also suggest that infected subjects have higher scores on Cloninger’s ST – self-transcendence (Novotná et al., 2005; Skallová et al., 2005). The NEO-PI-R questionnaire showed more extraversion in infected subjects, both men and women, and less conscientiousness in comparison with Toxoplasma-free subjects (Lindová et al., 2012). […]

infected men more often reported that diplomacy is not their strong point, that their instinctive (reflex) behaviour under imminent danger is rather slow and passive, that they believe that some people have the power to impose their will on others with hypnosis or through other means and that when they are attacked, physically or otherwise, or when they should fight for something important, they stop fighting at a certain moment because their own subconsciousness betrays them and they loss the will to fight back. The infected women more often report that diplomacy is not their strong point, that their instinctive (reflex) behaviour under imminent danger is rather slow and passive, that they believe that some people have the power to impose their will on others with hypnosis or otherwise and that they have a weak instinct for self-preservation: in situations where somebody else might be afraid, for example being alone in a forest at night or in an empty house, they remain calm. […]

Toxoplasma-infected subjects have prolonged reaction times, […]

The impaired psychomotor performance of infected subjects can explain the higher risk of traffic accidents and work accidents observed in four retrospective studies (Alvarado-Esquivel et al., 2012; Flegr et al., 2002; Kocazeybek et al., 2009; Yereli et al., 2006) […]

A double-blind observational study showed that Toxoplasma-infected men scored lower in clothes tidiness than uninfected men, whereas infected women scored higher (but not significantly so) than uninfected women (Lindová et al., 2006). Similarly, infected men scored lower and infected women scored higher in sociability. These outcomes match the results of the personality questionnaires. The infected rural male students scored higher in suspiciousness while infected rural female students scored lower in suspiciousness than their non-infected peers (Lindová et al., 2006), which again agrees with the results obtained with Cattell’s 16PF questionnaire. However, the very opposite was true for students of urban origin – infected male students showed lower and infected female students higher suspiciousness than their Toxoplasma-free peers. Using the method of experimental games, it was shown that both infected men and infected women were less altruistic than Toxoplasma-free subjects in the Dictator game while in the Trust game, the infected men were less altruistic and infected women were more altruistic than Toxoplasma-free men or women (Lindová et al., 2010). […]

infected male university students (age 19–22 years) have increased concentrations of testosterone (Flegr et al., 2008a; Flegr et al., 2008b) and, from photographs, their faces are rated as more masculine and dominant by females (Hodková et al., 2007). In contrast, infected female students have decreased levels of testosterone – which corresponds to decreased levels of testosterone in infected male and female mice (Kaňková et al., 2011). Infected male students are 3 cm taller than non-infected male students and both male and female students have a lower index finger to ring finger ratio (Flegr et al., 2005b), which is considered as an indication of being exposed to higher concentrations of testosterone during pregnancy (Manning, 2002). The increased concentration of testosterone was also recently reported in Toxoplasma-infected men, women (Shirbazou et al., 2011) and rats (Vyas, 2013).”

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