According to LiveScience, as reported in the Journal for Proceedings of the Royal Society — Biology, a parasite known for manipulating rat behavior also appears to have consequences for humans and indeed may have shaped whole cultures.

Toxoplasma gondii is carried by various warm-blooded mammals. Its effect on rats has been documented. Rats are normally very cautious around cats, for obvious reasons. Infection with the parasite makes them more likely to frequent areas marked by cat urine.

This is bad for the rats, but good for the parasite that uses the cat’s body as part of its lifecycle.

What of people, who often get infected through close contact with cats? Previous research has established an apparent connection between the parasite and schizophrenia. It damages special cells in the brain that are similarly damaged in schizophrenia. Likewise, when women who are infected give birth, the probability goes up that their children will later develop schizophrenia.

Now, research by Dr. Kevin Lafferty at the University of California, Santa Barbara implies a broader impact. Half of humanity is estimated to carry this parasite, so such a finding would have vast significance.

In humans, it appears to induce a kind of neuroticism labeled “guilt proneness.”

Infection is not evenly distributed across the globe. In fact, some countries are relatively free of the parasite while in others infection of people is almost universal.

Dr. Lafferty developed a hypothesis that widespread infection throughout a society could affect behavior at every level, and therefore in effect drive the society in certain directions.

His research focused on countries that scientifically track cultural data as well as levels of T. gondii infection. He found that high levels of T. gondii infection correlate to high levels of neuroticism.

He cautioned that, “Different responses to the parasite by men and women could lead to many additional cultural effects that are, as yet, difficult to analyze.”

What is the significance of this? First, if individuals and even whole populations can have something as fundamental as personality driven by a parasite it suggests a whole new approach to the treatment of mental illness. 

If this naturally occurring microbe can make a person neurotic for life, it should be possible to genetically engineer a different microbe that offsets this effect or induces calmness and equanimity.

But the consequences go well beyond this. In addition to the obvious risk of governments using this technology for “Brave New World” social engineering, there exists the very real present-day possibility that significant other aspects of human life are being unknowingly driven by microbes.

For example, “nanobacteria” are microscopic self-replicating structures smaller than viruses, whose behavior is so strange that scientists still debate whether or not theyre living organisms. These were discovered just a few years ago, yet are implicated in arteriosclerosis.

There’s no evidence that nanobacteria drive behavior. But the fact that they were unknown as recently as the early 1990s should give us pause.

Might other microbes be driving us in other ways? On the face of it, neurosis is not a self-serving behavior. Neurotics tend to be socially maladjusted and less happy than others. Yet human neurosis might serve the T. gondii, for example, by leading people to bond more closely with cats.

That strikes me as a very intelligent follow-on research study. I also hope that University of California researchers and their colleagues at other institutions are now moving to study the correlation between neurosis and this pathogen. Specifically, is it a one-to-one correlation or is neurosis sometimes caused by other factors?

The answer to that could drive the future of psychotherapy.

Going beyond this, it would not surprise me if subsequent research were to find other microbes implicated in other self-destructive human behaviors such as morbid obesity and anorexia, to name but two.

It’s also possible, of course, that neurosis is unique. All this beckons for further research.

How is this related to investments? Here’s how I see it: The discovery that a microbe can drive human behavior on a lifelong basis suggests the possibility of powerful new therapeutic modalities for treating mental illness.

I fully expect that as I write these words, researchers at some university are closely studying the lifecycle and infectious mechanisms associated in humans with lowly T. gondii. Their purpose is to fully understand it. Once understood, the microbe could be genetically modified for all kinds of other purposes, including “crowding out” the naturally occurring variety.

What would it be worth to have a vaccine against neurosis? That’s but one shining promise here.

To your profitable future,
Jonathan Kolber
December 3, 2007

P.S.: I recently told my Emerging Capital Report readers about a small, under-the-radar pharmaceuticals pioneer that has brought America’s most dreaded disease to its knees… This tiny company is on the verge of making investors some big money.

Investigating Human Behavior was originally featured in the Penny Sleuth.