Mind Controlling Parasites

August 30, 2010

Torah Kachur

Science in Seconds news alert!!  New wave of terrorist weapons - Mind Controlling Infections


Okay, Bin Laden isn't funding biotech labs in caves in Afghanistan and Ss is not in the business of fear-mongering, but the idea that infections can control behaviour goes beyond syphilis tunneling holes in Shakespeare's brain. 


There are many different parasitic infections that control the brain of the host - mostly in insects but in rats and humans as well.  Toxoplasma gondii is a parasitic microbe that has a freaky infection cycle.  Normally infecting the brains of rats, it only sexually reproduces in the gut of cats then is spread through cat poo.  Cats and rats generally don't play well together so the parasite is left with a bit of a problem. 


The solution - take over the brain of the infected rat and force it to like cats, the dispicable rat will like cats so much it will seek them out.... only to get eaten. 

         Torah Kachur Science in Seconds Toxoplasma cat infection parasite mind-control

Normally, the scent of cat pee is pretty offensive to rats (and humans alike) and they exhibit reactions akin to fear when they smell it.  Which makes evolutionary sense - rats should be scared of cats and all the smells associated with them.  But, Toxoplasma controls the rat brain to make it think it actually likes the smell of cat pee, and only cat pee.  In other words, this infection can manipulate the brain to turn fear into friend.  


It is unclear how this tiny protozoa can manipulate a single fear response - but infections seem to localize to a region in the brain known as the amygdala - a region associated with fear responses.  This type of research is scary (pardon the pun), we like to think the human mind is above biology - something ethereal and beyond understanding.  But, a simple protozoa can evolve a way to target a specific fear in rats (which are essentially small humans from a scientific standpoint).


So the next obvious question - are humans subjected to Toxoplasma infections?  And does this explain cat lovers?


Yes, humans can be infected by the parasite and infection rates are an estimated 60 million in the US (20% of the population).  Infection has been linked to everything from an increased car accident rate, to a driving force in human culture, to schizophrenia.


There are 38.2 million households with at least one cat.  This may finally explain it.



Email (optional)


© 2010 Science in Seconds. All rights reserved.     Disclaimer  |  Contact  |  Subscribe
Friend Science in Seconds on Facebook Follow Science in Seconds on Twitter Science in Seconds RSS Feed