
Rage Disorder Linked with Toxoplasmosis (2016) - stephengillie
https://www.scientificamerican.com/article/rage-disorder-linked-with-parasite-found-in-cat-feces/
======
lima
Toxoplasmosis is an extremely interesting parasite. I wouldn't be surprised if
it is recognized as an important public health issue in the coming decade.

Is has been linked to all sorts of disorders, including schizophrenia and
bipolar disorder. Prof. Jaroslav Flegr contributed many important studies,
especially in the early stages of toxoplasmosis research [1]. He was also
featured by an Atlantic article, which was one of the first to bring public
attention to the field of research [2].

One particularly interesting finding is how it interacts with the RH factor.
It might explain the relative stability of the distribution of the two types
in the population even though one of them should have a serious disadvantage
(birth complications) [3].

The hard question is how to prevent it. Due to how many different infection
vectors there are, the only sound pieces of advice are "eat your meat well
done" and "avoid getting in contact with garden soil". Development of a
vaccine for cats is a promising solution since the parasite can only be
transmitted by cats.

[1]:
[https://web.natur.cuni.cz/flegr/publ.php](https://web.natur.cuni.cz/flegr/publ.php)

[2]: [https://www.theatlantic.com/magazine/archive/2012/03/how-
you...](https://www.theatlantic.com/magazine/archive/2012/03/how-your-cat-is-
making-you-crazy/308873/)

[3]:
[https://web.natur.cuni.cz/flegr/pdf/rhWho.pdf](https://web.natur.cuni.cz/flegr/pdf/rhWho.pdf)

~~~
sillysaurus3
After learning about the perverse incentives for publishing scientific papers,
I find it extremely difficult to trust new research. Any tips for reversing
this mindset? I know it's not too great to be feeling this way.

Scientists have immense incentives for publishing new results. As someone
quipped, "there is no cost in getting something wrong; the cost is not being
published."

Toxoplasmosis in particular seems intuitively like the perfect combination of
new research plus massive prestige for whoever publishes papers on the topic.
And we can't trust articles written on the topic either; they do little more
than parrot whatever the scientists say, and don't really cast a critical eye
on the methodology or findings.

Which makes sense. I mean, how could they? None of us are experts the way a
scientist is an expert. But it used to be a hobby of mine to dig through
research papers and find subtle inconsistencies. Take fatal familial insomnia,
for example. It's not fatal due to the insomnia. That's a misnomer. But the
fact that it wasn't related to the insomnia was buried on the 7th page of the
report as basically a footnote.

I don't know. I just wish it were easier to take a lot of this at face value.

~~~
epistasis
>Toxoplasmosis in particular seems intuitively like the perfect combination of
new research plus massive prestige for whoever publishes papers on the topic

Eh, not really much prestige, but perhaps lots of press.

The big thing is to not take any single paper as "scientific truth" like what
you read in a textbook. The scientific literature is not a textbook, it's the
place where science's self-correction happens. Things in text books have been
battle-tested, and widely accepted usually due to replication. And even then,
textbooks have errors and perpetuate some falsehoods! Any individual
scientific paper will not even likely be replicated, because it's working on
something that did not turn out to be fundamental to the path of science.

Scientific papers in the literature are how scientists share their small steps
while exploring the n-dimensional world. That n is very high, so there are
lots of directions to explore, and most of them will not be that interesting.
If it is, somebody else may decide to take a look too. If it's a hot-topic,
then many many people will. Scientists have to operate in a world where they
are exploring what is and is not true, and their relationship with uncertainty
is strong; it's absolutely essential to embrace uncertainty.

The biggest thing is to distrust news reporting about science. It's correct
about 1% of the time. The motivations of a reporter trying to somehow make an
interesting article by deadline on a topic they don't understand are far more
distorted than the scientists publishing a paper they expect 30-50 people to
ever read. And that's if you actually get a real reporter to look at these
things; most articles are just press releases that are cut and pasted from a
university press lackey into the newspaper's publishing system. Those are
usually even worse.

~~~
asdfgadsfgasfdg
> And that's if you actually get a real reporter to look at these things; most
> articles are just press releases that are cut and pasted from a university
> press lackey into the newspaper's publishing system. Those are usually even
> worse.

Actually if the researchers expect the paper to be high impact they will often
provide the press release to the University's press department themselves -
these types of press releases are merely a layman directed abstract and tend
to be reasonably OK.

This raises two interesting points.

1\. Sometimes the lowest quality newspapers have the best quality article on a
given publication.

2\. Why aren't all research publications required to be accompanied by a
second abstract written in plain low jargon language that can be understood at
some level by someone with high school science?

~~~
vilhelm_s
I think maybe it depends a little bit on which university it is: perhaps a
small university will not have enough money to hire a big dedicated PR office,
so they will rely more on materials submitted directly by the scientist and
stick closer to reality. But the PR offices of big universities (in particular
MIT) put out pure hype which is very precariously connected to reality. A lot
of work goes into these press releases (they will send someone from the PR
office to interview the researcher and so on), but the work is not really
aimed towards providing an accurate summary of the research...

~~~
gumby
As an MIT graduate I sadly concur with this statement.

------
Pigo
Joe Rogan has talked about this at length on his show several times, and had
Robert Sapolsky as a guest to talk about this.

They actually say the parasite causes rats to become sexually attracted to
cats, causing them to pass on to the cat once it's inevitably killed. Life
sure does find a way.

[https://www.youtube.com/watch?v=NroiGfNohPo](https://www.youtube.com/watch?v=NroiGfNohPo)

~~~
nealabq
If you're starting a family, consider these words from Robert Sapolsky:

"The parasite my lab is beginning to focus on is one in the world of mammals,
where parasites are changing mammalian behavior. It's got to do with this
parasite, this protozoan called Toxoplasma. If you're ever pregnant, if you're
ever around anyone who's pregnant, you know you immediately get skittish about
cat feces, cat bedding, cat everything, because it could carry Toxo. And you
do not want to get Toxoplasma into a fetal nervous system. It's a disaster."

"There's a long-standing literature that absolutely shows there's a
statistical link between Toxo infection and schizophrenia. It's not a big
link, but it's solidly there. Schizophrenics have higher than expected rates
of having been infected with Toxo, and not particularly the case for other
related parasites. Links between schizophrenia and mothers who had house cats
during pregnancy."

[https://www.edge.org/conversation/robert_sapolsky-
toxo](https://www.edge.org/conversation/robert_sapolsky-toxo)

~~~
piyh
Can also really fuck up your eyes

[https://aapos.org/client_data/files/2015/1230_fig2congenital...](https://aapos.org/client_data/files/2015/1230_fig2congenitaltoxoscar.jpg)

~~~
woliveirajr
And when you have that black hole very close (or over) that light part, it
means that your toxo lesion is over the sport where all your eye nerves go,
and then you become blind. Or almost, depending the exact position. Or you are
"cured" but keep seeing eye floaters for the rest of your life.

------
woliveirajr
The treatment for Toxo isn`t a easy one: when thing get serious you take
massive doses of pyrimethamine and sulfadizine, for example, and have to take
extra folinic acid (not folic, folinic).

And it won't kill all T. Gondii, it will remain latent inside your body.

There were some studied, few years ago, about combining pyrimethamine and
aminoacids to kill the latent toxo, but I didn't find the results, if it even
worked or not.

For almost everybody, infection will go away without signs. For few others, it
will make you remember it for the rest of your life.

~~~
ajmurmann
Thank you for this explanation! I listened to a long radio special about
behavior assuring parasites a long time ago. Toxoplasma Gondii played a big
role in the report and ever since I've been dumbfounded why we don't treat it.
Even though it doesn't seem to have a negative immediate health benefit
behavior alteration especially towards higher risk taking is terrifying to me.
Thanks to your explanation of the cost of treatment this makes more sense.

------
phkahler
They say about 20 percent of the US population has been infected and then we
see this:

The research team found that 22 percent of the people with IED tested positive
for toxoplasmosis exposure, compared with only 9 percent of the healthy
control group. About 16 percent of the group with other psychiatric disorders
tested positive for toxoplasmosis, too.

So the people with IED had about the same rate of infection as the general
population. This looks to me like one of those "nothing to see here"
situations based on the numbers.

~~~
AnimalMuppet
Maybe not. That 9% number for the control group stands out. That number and
the 20% number for the population as a whole seem to me to be incompatible -
or, perhaps, measured in different ways.

If the 9% healthy and 22% with IED are both accurate (and the 20% number is
the one that's off), then there may in fact be something to see here.

------
Ovah
Years ago I attended a lecture on Toxoplasmosis gondii. Intriguing
(unattributed) points made by the scientist: 1) there's a higher prevalance of
infection in car crash victims than control 2) by hijacking dendritic cells
(blood immune cell), the parasite is able to bypass the blood brain barrier
(highly protective filter of brain) 3) once in the brain, it may form cysts
that may lay dormat 4) a significant portion of the world population is
infected 5) if have cats weren't allowed as pets, there would hardly be any T.
gondii infections

------
ajmarcic
Toxoplasmosis is naturally contracted from cat exposure and care.

Anecdotally I see mentally ill people as being drawn to cat ownership for
their personal comfort and fascination.
[https://en.wikipedia.org/wiki/Louis_Wain](https://en.wikipedia.org/wiki/Louis_Wain)

It is a difficult leap to go from saying "people with certain mental illnesses
own cats, and thus are likely to have TP" to "TP causes mental illness".

If we are to believe cat owners are more likely to have mental illness, a
correlation of mental illness and TP serum positivity follows naturally.

~~~
nerpderp83
Are you saying people with mental illness seek comfort via pets (cats).
Shouldn't we see an affinity for other social pets besides cats?

~~~
shubb
You could probably answer this question using this resource [1].

However, someone used it to show no associations between psychotic episodes
(specifically) AFTER controlling for other factors (that are associated with
cat ownership)[2].

Using the adjustments they made, I could wildly speculate that possibly dog
owners will be less likely than cat owners to have mental illness, because
dogs require a certain amount of wealth, living space, etc - and the lack of
these things is associated both with cat ownership and mental illness, maybe,
just not in rural areas...

[1][http://www.bristol.ac.uk/alspac/researchers/access/](http://www.bristol.ac.uk/alspac/researchers/access/)
[2][https://www.cambridge.org/core/journals/psychological-
medici...](https://www.cambridge.org/core/journals/psychological-
medicine/article/curiosity-killed-the-cat-no-evidence-of-an-association-
between-cat-ownership-and-psychotic-symptoms-at-ages-13-and-18-years-in-a-uk-
general-population-cohort/75C9A48B669BE36E947AFB0BC5CB00CA/core-reader)

------
jhanschoo
Note that toxoplasmosis is extremely common and is sufficiently benign for
most people that it does not really warrant worry or concern from the general
populace. There are more important and actionable factors affecting most of
us.

~~~
tartuffe78
Said the parasite!

------
oldsklgdfth
Robert Sapolsky, a neuroscientist, talking about toxoplasmosis.

[https://www.youtube.com/watch?v=m3x3TMdkGdQ](https://www.youtube.com/watch?v=m3x3TMdkGdQ)

He touches on some very interesting observations that have been made about the
infection and behavior.

------
averagewall
This is the same parasite that supposedly causes mice to become permanently
unafraid of cats and attracted to cat urine.

~~~
slig
There are videos showing mice going after cats and the cats know instinctively
that there's something very wrong and they run away.

~~~
bogomipz
Do you have a link?

~~~
slig
This is not the video I had in mind, but here it is
[https://youtu.be/XQ4Y27RQaZk](https://youtu.be/XQ4Y27RQaZk)

------
HillaryBriss
> _It correlates also with diseases burden associated with bipolar disorder,
> obsessive compulsive disorder, and epilepsy_

though the headline does not emphasize it, there's an OCD correlation too.

------
prepaciously
It makes one wonder how healthy those home-grown salad vegetables might really
be, given that a garden plot makes a convenient litter tray for roaming
felines.

~~~
planteen
What makes you think commercial fruits & vegetables are any different? Nearly
every farm has tons of feral cats around.

~~~
prepaciously
I must admit I didn't know about the feral cats wandering around farms. But I
do imagine that farmers wash their produce more _consistently_ than home
growers do, and that feline density is higher in the suburbs.

------
FranOntanaya
I imagine people that grow up around stray cats are likely to have a different
upbringing to people that don't.

~~~
codingdave
That statement is a tautology. What exactly are you trying to imply by it,
though?

~~~
racer-v
I imagine GP is suggesting correlation as opposed to causation.

------
fnord123
This is consistent with research linking Toxoplasmosis with PMDD [0]

[0]
[https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5012242/](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5012242/)

------
antidaily
So I had a thing with this as a young kid. It caused burn-like scars on my
retina. No symptoms after that or vision changes. Did it alter my brain? I
don't _think_ so. I will rage in my car when someone is in the left lane
driving slow.

~~~
eritain
There is so much visual processing machinery in the retina that some
neuroscientists describe it as an outpost of the visual cortex. In that sense,
scarring your retina might indeed have altered your brain. But not in a way
that's related to emotional control.

~~~
jpfed
Your eyes are also an outgrowth of the neural tube.

------
theyregreat
If it makes rats sexually attracted to cats, it may not be such a trivial
disease.

------
Dowwie
I can see attorneys using this as a defense going forward

~~~
nerpderp83
Honorable Members of the Jury, you can clearly see that my client couldn't
possibly be responsible for his actions, as he just ingested a Twinkie with a
Soft Nougatie Cat Feces Filling!

------
ggm
reversible? or permanent brain function change?

