Science Fiction Dictionary
A  B  C  D  E  F  G  H  I  J  K  L  M  N  O  P  Q  R  S  T  U  V  W  X  Y  Z

 

Toxoplasma Gondii Parasite Mind Control

Half of the world's human population is infected with Toxoplasma. Parasites in the body - and the brain. Remember that.

Toxoplasma gondii is a common parasite found in the gut of cats; it sheds eggs that are picked up by rats and other animals that are eaten by cats. Toxoplasma forms cysts in the bodies of the intermediate rat hosts, including the brain. Since cats don't want to eat dead, decaying prey, Toxoplasma takes the evolutionarily sound course of being a "good" parasite, leaving the rats perfectly healthy. Or are they?


(Toxoplasma gondii)

Oxford scientists discovered that the minds of the infected rats have been subtly altered. In a series of experiments, they demonstrated that healthy rats will prudently avoid areas that have been doused with cat urine. In fact, when scientists test anti-anxiety drugs on rats, they use a whiff of cat urine to induce neurochemical panic. However, it turns out that Toxoplasma-ridden rats show no such reaction. In fact, some of the infected rats actually seek out the cat urine-marked areas again and again. The parasite alters the mind (and thus the behavior) of the rat for its own benefit.

If the parasite can alter rat behavior, does it have any effect on humans? Dr. E. Fuller Torrey (Associate Director for Laboratory Research at the Stanley Medical Research Institute) noticed links between Toxoplasma and schizophrenia in human beings, approximately three billion of whom are infected with T. gondii:

  • Toxoplasma infection is associated with damage to astrocytes, glial cells which surround and support neurons. Schizophrenia is also associated with damage to astrocytes.
  • Pregnant women with high levels of antibodies to Toxoplasma are more likely to give birth to children who will develop schizophrenia.
  • Human cells raised in petri dishes, and infected with Toxoplasma, will respond to drugs like haloperidol; the growth of the parasite stops. Haloperidol is an antipsychotic, used to treat schizophrenia.
Dr. Torrey got together with the Oxford scientists, to see if anything could be done about those parasite-controlled rats who were driven to hang around cat urine-soaked corners (waiting for cats). According to a recent press release, it turns out that haloperidol restores the rat's healthy fear of cat urine. In fact, antipsychotic drugs were as effective as pyrimethamine, a drug that specifically eliminates Toxoplasma.

Are parasites like Toxoplasma subtly altering human behavior? As it turns out, science fiction writers have been thinking about whether or not parasites could alter a human being's behavior, or even take control of a person. In his 1951 novel The Puppet Masters, Robert Heinlein wrote about alien parasites the size of dinner plates that took control of the minds of their hosts, flooding their brains with neurochemicals. In this excerpt, a volunteer strapped to a chair allows a parasite to be introduced; the parasite rides him, taking over his mind. Under these conditions, it is possible to interview the parasite; however, it refuses to answer until zapped with a cattle prod.

He reached past my shoulders with a rod. I felt a shocking, unbearable pain. The room blacked out as if a switch had been thrown.. I was split apart by it; for the moment I was masterless.

The pain left, leaving only its searing memory behind. Before I could speak, or even think coherently for myself, the splitting away had ended and I was again safe in the arms of my master...

The panic that possessed me washed away; I was again filled with an unworried sense of well being...

"What are you?"
"We are the people... We have studied you and we know your ways... We come," I went on, "to bring you peace.. and contentment-and the joy of-of surrender." I hesitated again; "surrender" was not the right word. I struggled with it the way one struggles with a poorly grasped foreign language.
"The joy," I repeated, "-the joy of . . .nirvana." That was it; the word fitted. I felt like a dog being patted for fetching a stick; I wriggled with pleasure.

Still not sure that parasites can manipulate the behavior of host organisms? Consider these other cases:

  • The lancet fluke Dicrocoelium dendriticum forces its ant host to attach to the tips of grass blades, the easier to be eaten. The fluke needs to get into the gut of a grazing animal to complete its life cycle.
  • The fluke Euhaplorchis californiensis causes fish to shimmy and jump so wading birds will grab them and eat them, for the same reason.
  • Hairworms, which live inside grasshoppers, sabotage the grasshopper's central nervous system, forcing them to jump into pools of water, drowning themselves. Hairworms then swim away from their hapless hosts to continue their life cycle.

Not all science-fictional parasites are harmful; read about the Crosswell tapeworm from Brian Aldiss' 1969 story Super-Toys Last All Summer Long, which keeps people who overeat from becoming obese. Not to mention robots based on parasites. Read press release on evidence for link between Toxoplasma and schizophrenia, Suicidal grasshoppers. Story via blogger Carl Zimmer and his readers.

Scroll down for more stories in the same category. (Story submitted 2/7/2006)

Follow this kind of news @Technovelgy.

| Email | RSS | Blog It | Stumble | del.icio.us | Digg | Reddit |

Would you like to contribute a story tip? It's easy:
Get the URL of the story, and the related sf author, and add it here.

Comment/Join discussion ( 45 )

Related News Stories - (" Medical ")

Drug To Regenerate Teeth In Humans
'We want to do something to help those who are suffering from tooth loss or absence,' said lead researcher Katsu Takahashi.

Illustrating Classic Heinlein With AI
'Stasis, cold sleep, hibernation, hypothermia, reduced metabolism, call it what you will - the logistics-medicine research teams had found a way to stack people like cordwood and use them when needed.' - Robert Heinlein, 1956

Brainoware Reservoir Computation Of Biological Neural Networks
'Head cheese. Cultured brains on a slab.' - Peter Watts, 1999.

Forward CarePod The AI Doctor's Office
'It's an old model,' Rawlins said. 'I'm not sure what to do.'

 

Google
  Web TechNovelgy.com   

Technovelgy (that's tech-novel-gee!) is devoted to the creative science inventions and ideas of sf authors. Look for the Invention Category that interests you, the Glossary, the Invention Timeline, or see what's New.

 

 

 

 

Science Fiction Timeline
1600-1899
1900-1939
1940's   1950's
1960's   1970's
1980's   1990's
2000's   2010's

Current News

LORIS Passive-Gripper Climbing Robot
'At the end of each appendage's eight fingers there are tinier appendages...'

Neuroplatform Human Brain Organoid Bioprocessor Uses Less Electricity
'Cultured brains on a slab.'

Drug To Regenerate Teeth In Humans
'We want to do something to help those who are suffering from tooth loss or absence,' said lead researcher Katsu Takahashi.

Coin-Sized Nuclear Battery Good For 100 Years
'...power pack the size of a pea.'

Live Stream With Meta-Ban Multimodal Smart Glasses
'...the bug-eyed, opaque gape of her True-Vu lenses.'

'Autonomous' Waymo Improves Driving With Remote Human Operators
'...some bored drone pusher in a remote driving centre has got your life... in his hands.'

Will Whales Be Our First Contact?
'He had piloted the Adastra to its first contact with the civilization of another solar system.'

Heinleinís Controlway - Connected and Automated Vehicle (CAV) Corridor In Michigan
'Well, that's us,' said Lazarus.

NYC/Dublin Portal Fails To Meet 'Guardian Of Forever' Standards
I am the Guardian of Forever.

SliceIt! Why Not Teach Robots To Use Knives?
'One building now gushed forth smoke and another stench that was unmistakable.'

FLOAT Levitating Train On The Moon ala Clarke
'The low-slung monorail car, straddling its single track, bored through the shadows on a slowly rising course.'

Singapore Writers Push Back On LLM Training
'...we've promised him a generous pension from the royalties.'

SpaceX Intros Extravehicular Activity Suit
'Provision had been made to meet the terrific cold which we knew would be encountered the moment we had passed beyond the atmosphere.'

Athena Smart Security Guard Robot With Face Recognition
'You are who we say you are, Dr. Dakin,' Turner said.'

The FLUTE Project - A Huge Liquid Mirror In Space
'It's area, and its consequent light-gathering capacity, was many times greater than any rigid mirror...'

Robot Preachers Found To Undermine Religious Commitment
'Tell me your torments,' the Padre said, in an elderly voice marked with compassion.

More SF in the News Stories

More Beyond Technovelgy science news stories

Home | Glossary | Invention Timeline | Category | New | Contact Us | FAQ | Advertise |
Technovelgy.com - where science meets fiction™

Copyright© Technovelgy LLC; all rights reserved.