Feeds

Common brain parasite 'can affect host's actions'

One-in-five chance your mind is being manipulated

Choosing a cloud hosting partner with confidence

Boffins here in Blighty say that a brain parasite which is carried by up to 20 per cent of the population is capable of affecting its host's actions for its own benefit – but against the interests of the host.

The parasite in question, Toxoplasma gondii, has now been found to "directly affect" the production of dopamine, a key chemical messenger in the human brain. Dopamine levels are implicated in human illnesses such as attention deficit hyperactivity disorder, Parkinson's disease and schizophrenia.

Toxoplasma gondii's primary host organism is cats, but it can also live in other creatures including humans and rats. Humans are infected with it by eating unwashed vegetables with cat poo on them: it's estimated that between 10 and 20 per cent of Brits carry the protozoan parasite and perhaps 22 per cent of Americans. Normally the hidden brain invader appears to have little effect on a human host, though it can kill in certain cases – for instance in the case of someone whose immune system isn't working.

It's been known for some time that T gondii has a more serious effect on rats and mice, in which they lose their fear of cats or even become attracted to them. This is obviously bad news for the host, as it tends to get killed and eaten, but good news for T gondii as it gets to infect another cat where it can reproduce.

Now, scientists working in Britain and the USA have shown for the first time that T gondii can affect production of dopamine in the brain of a rat host – offering a clue as to how it can manipulate rats' behaviour, and perhaps giving insights into problems of the human brain also. According to a statement issued by Leeds uni announcing the research:

Dopamine is a natural chemical which relays messages in the brain controlling aspects of movement, cognition and behaviour. It helps control the brain's reward and pleasure centres and regulates emotional responses such as fear. The presence of a certain kind of dopamine receptor is also associated with sensation-seeking, whereas dopamine deficiency in humans results in Parkinson's disease.

"Based on these analyses, it was clear that T gondii can orchestrate a significant increase in dopamine production in neural cells," says Dr Glenn McConkey of the Leeds' Faculty of Biological Sciences.

"Humans are accidental hosts to T gondii and the parasite could end up anywhere in the brain, so human symptoms of toxoplasmosis infection may depend on where parasite ends up. This may explain the observed statistical link between incidences of schizophrenia and toxoplasmosis infection."

The full research paper can be read here, published by the journal PLoS ONE. ®

Secure remote control for conventional and virtual desktops

More from The Register

next story
GRAV WAVE DRAMA: 'Big Bang echo' may have been grit on the scanner – boffins
Exit Planet Dust on faster-than-light expansion of universe
Mine Bitcoins with PENCIL and PAPER
Forget Sudoku, crunch SHA-256 algos
SpaceX Dragon cargo truck flies 3D printer to ISS: Clawdown in 3, 2...
Craft berths at space station with supplies, experiments, toys
'This BITE MARK is a SMOKING GUN': Boffins probe ancient assault
Tooth embedded in thigh bone may tell who pulled the trigger
DOLPHINS SMELL MAGNETS – did we hear that right, boffins?
Xavier's School for Gifted Magnetotaceans
Big dinosaur wowed females with its ENORMOUS HOOTER
That's right, Doris, I've got biggest snout in the prehistoric world
Japanese volcano eruption reportedly leaves 31 people presumed dead
Hopes fade of finding survivors on Mount Ontake
That glass of water you just drank? It was OLDER than the SUN
One MEELLION years older. Some of it anyway
Canberra drone team dances a samba in Outback Challenge
CSIRO's 'missing bushwalker' found and watered
prev story

Whitepapers

Forging a new future with identity relationship management
Learn about ForgeRock's next generation IRM platform and how it is designed to empower CEOS's and enterprises to engage with consumers.
Storage capacity and performance optimization at Mizuno USA
Mizuno USA turn to Tegile storage technology to solve both their SAN and backup issues.
The next step in data security
With recent increased privacy concerns and computers becoming more powerful, the chance of hackers being able to crack smaller-sized RSA keys increases.
Security for virtualized datacentres
Legacy security solutions are inefficient due to the architectural differences between physical and virtual environments.
A strategic approach to identity relationship management
ForgeRock commissioned Forrester to evaluate companies’ IAM practices and requirements when it comes to customer-facing scenarios versus employee-facing ones.