Mind-controlling Parasites! 

I can't look at my cat anymore

so if you get a cat you will get brainwashed to love cats even more?

It's important to note a few things about toxo and cats: first, not all cats have are infected with the parasite. Cats that stay in the house and only eat cooked meat have a much lesser risk of carrying the parasite. They also only shed it in their feces for a certain period of time after the infection and won't be infectious for all of their life. Second, for most people toxo isn't dangerous and many won't have any symptoms. That's usually the case for healthy people with a well functioning immune system, that can take good care of the parasite. Third: there are other ways one can be infected with the oocysts that don't require a cat, such as from soil or water that has been contaminated. Even some raw meat or unwashed fruits can be infectious. Wash your hands often, wash your fruits and vegetables well before consumption and you are good. And try not to eat raw meat. The infection is however very dangerous for pregnant women (well, the infant due to their lack of immunity) and those with a compromised immune system (such as organ transplant receivers and people with AIDS). Generally I dislike the emotion-driven dislike against cats and cat owners that stems from ignorance. Toxo is a serious thing, especially for risk groups, but some people let their stereotypes about "crazy cat ladies" go to their heads which isn't very beneficial in actually taking measures to prevent an infection or spread of the parasite. Plus, dogs can have just as many gross parasite to pass on to humans, such as the fox tapeworm. If it were just because of that, no one should ever be close to another animal or have a pet. The key, which should be more communicated, is to be more careful with hygiene, the handling of meat and foods in general and of course, keeping good care of your cat (if you have one). I found this site had useful tips: www.cdc.gov/parasites/toxoplasmosis/gen_info/faqs.html#spread

Toxoplasmosis is also transmitted by birds like pigeons, so don't worry people, you can still get it even if you stay away from cats :D

So crazy cat ladies are actually being mind controlled?

2:29 You’re welcome all AP Bio students

"But little does it know that that poo has a baby little worm larvae in it that's going to hijack its brain, turn it into a zombie, and drive it's body around like a go-cart." That is both slightly horrifying and hilarious. XD

So that's how the bankers are doing it!

My parasitology professor played this in class~! I was so excited, I almost yelled "HANK!" when it began playing XD

I'm surprised he didn't mention Cordyceps.

I can not thank you enough for all of these videos. In biology im doing a work on epigenetics while im in english is about to hold a speech about parasites. Your videos help me so much. I THANK YOU A THOUSAND TIMES OVER

Great job! Informative AND entertaining!

My mom got toxoplasmosis. It was in her eye, so she can't so very well out of that eye and now has practically no depth perception. She does not drive well now. And we have three cats.

Amazing how much Hank has improved as a narrator these past few years.

You should make another episode or perhaps an erratum about the fungus that turns ants into zombies. That is really amazing. Keep up the good work man, your videos are absolutely brilliant!

love this show!! keep up the good work

Wouldn't you just like to spoon a cat? lol

Crazy cat lady phenomenon...

love how there is an add for a movie about mind control with codes for this video

new favourite channel

did this remind anyone of animorphs?

Damn. I clean the cat litter everyday... Well I'm infected. THANKS TOXOPLASMA!

Correlation does not imply causation! There was a great report in the last few months on some public radio show (radio lab maybe?) that compared competing arguments for and against Toxo related symptoms. There was even one that suggested that the parasite interferes with our perception of speed!

This is the greatest episode of all!!! 😂

I love cats but I don't eat cat poop!

Reminds me of the Goa'uld...

I should have been asleep days ago but I can't stop watching and re-watching these videos.

OMG! i love this show

And I just watched the human parasites video...

And I was thinking about the anime Kiseijuu (Parasyte)

funniest Scishow Ep. Ever

I won't be able to go to sleep for a week now, thanks Hank!

who else came here for information on cordyceps

I just sent this video to my mom, she has like 15 cats. email subject, BRAIN WORMS!! Yes, I'm such a wonderful son. :)

i love your spech very much and your explanation super video

Rofl, I love your use of obscenities in combination with science. Very entertaining and very well researched too. Subscribed.

Why would that make us schizo? Wouldn't it just make us want to spoon with our cats?

DAMN NATURE, YOU SCARY

LOL "these little bastards".... *laptop covered in pepsi nasal mist*

Great video.

what about the mushrooms that mind control a ant to go to a good rooting position and then turn the ant into a mushroom

Glad I'm a dog person.

Oh my god. I got an advertisement for the new evil dead, and that combined with mind control parasites scared the crap out of me!!!

keep up the good work!

sooo my parasitic worm in plague inc is one of the few to take over the brain? good to know... (I'VE GOT TO GET OUT OF HERE... THEY KNOW!!!!!!)

WOW weird?!

Notes from Scott Westerfeld's "Peeps": For some reason the trematodes always infect the snail's left eyestalk Birds never evolved to avoid the glowing snails because the trematodes do no harm to the birds.. About 50% of the human population has toxoplasma in their brains. It was observed that men with toxo -don't shave everyday -don't wear ties too much -don't like following social rules Women with toxo -like to spend money on clothes -tend to have a lot of friends -seem more attractive than non-infected women for some reason Researchers found that in general the infected are more interesting to be around. People without toxo -like following the rules -are more likely to pay back borrowed money -show up for work on time -the men get into fewer fights -the women have fewer boyfriends But maybe some people always hated going to work on time and realized that if cats had to go to work, they would be late too. They adopted cats and then got toxo. Maybe the other people got dogs who followed the rules. Fetch. Sit. Stay. Their brains stayed toxo free. But maybe not. Maybe the infected were already infected and were driven to get cats. Chicken or the egg?

ya i've seen that one a few years ago, probably the most terrifying thing i've ever heard of that occurs naturally

anyone here played parasite eve?

yet another reason not to own a cat 😵

This is amazing!

Oh thank you so much for making this video I'm hyper paranoid and pathologically afraid of bugs and parasites larger than 1 millimeter and I was eating.

but I love my cats :(

Cat:*snuggles my face*. Me:Please don't give weird parasites

Oh man.. this topic with that weird fluttery greenscreen effect. If im looking at hank, all that movement in my peripheral vision just looks like creepy crawlies all moving around. Surprisingly effective combo, intended or not.

Thanks for making my day xD

this was so funny, the way u presented it.

I love you hank

1:40 "I'll see you one of those, and... raise you, a hair-worm. These little... BASTARDS!..." Emotionally one of the most awesome sentences I've ever heard come out of Hank.

Now you have to wonder whether it's you who loves your cat or the wooorrrrrmmm......

you are really channeling Geoff Goldblum in this episode, Hank!

you're my hero

"...Wouldn't you love to spoon a cat?" best line I have heard all day. On a side note, your videos are great. I really enjoy bouncing around your channel. =)

Just finished Crash Course and tuned into VLogBrothers and Scishow. You guys are great! On the subject of parasites, I was wondering if rabies would come up. I don't know much about it, but thought it had the property of getting into someone's brain and making them go crazy - such that it could be blocked and treated before getting into the brain, but not afterwards. Not sure if that's correct though. I'm curious about it, so consider this my request for rabies as a scishow topic.

there's a bug called a jewel beetle (?) that's native to NA and first stings a particular kind of cockroach - paralysing only it's front legs, and then does a kind of brain surgery to it making it a zombie. It then lays it's eggs inside the cockroach and the larvae have fresh food when they hatch.

Somewhere I once saw someone say that said if you've ever come into contact with cat feces through one means or another, you've got a 50% chance of developing schizophrenia. And then I began to twitch at the terrible misuse of statistics.

Two parasite videos, one of which is about mind control, and no mention of Cordyceps? I think this would be a great topic! (Especially with the recent release of the PS3 game The Last of Us which is all about human cordyceps and that is a damns terrifying idea)

There's a type of parasite that attaches to crabs and takes over the crab's mind. I forgot what it's called, but it feeds off the crab and makes the crab try to help the parasite eggs spread.

Well what I've read, the same parasite that affects rats can also affect humans by taking away fear and slowing us down by emiting some chemical in our brain that gives a slight sense of euforia. Thus the thing is pretty much fucking around with our brain chemistry. So while it might not "yet" give us direct orders, it certainly does make us less afraid and more careless about the danger.

Yes they are brothers...They have a channel together called 'vlogbrothers' More on that matter, Hank hosts the monthly game show on Mental Floss.

Radiolab podcasts on iTunes has an episode about this. There's research that suggests toxo leads to somewhat more reckless driving, and rash decisions.

The voices..they speak to me....they tell me....to love cats? I honestly cant argue with that train of thought.

i find it very hard to eat and watch this at the same time.

Scishow I hope you lose as much sleep making these videos as I do watching them.

It would be neat to observe the physical interaction between parasite and host. What is connected to where and what is being transferred or propagated between the two that would explain the change in behavior. Makes me wonder if you could fight off a parasite with will power alone.

When I first watched about that in a Discovery documentary in class I had nightmares for a week. Ironically, the girl sitting near me had a panic attack when it moved on to spiders.

Let's see what wonderful Scishow has to show me today!....o_o

I think his also relates to Paralysis ticks if you get one on your head you cannot think straight, specifically about the possibility of having a tick, this has happened to myself and to 2 others that I know.

I have read of some research where the toxo parasite makes cat urine smell good to other mammals. This is why the rats are attracted to the cats. It also is speculated why certain people horde cats. Not surprisingly they were found to have high toxo levels in their systems.

You forgot to mention the sugar addiction caused by a systemic yeast infection. Chronic obesity and bad acne caused by systemic yeast that ALSO makes you feel absolutely horrible when not consuming massive quantities of sugar, which has the wonderful side effect of lowering the immune system's defensive capability against said yeast by increasing the basic acidity of the body tissues (via massive amounts of sucrose which causes the kidneys to retain more water). Scary stuff, but all true.

Imagine if you heard voices but it started early childhood so you grew up just thinking of them as your own "sudden insights" instead of conceptualizing them as voices in your head? But then your immune system would probably be brought on board with the process resulting in human symbiosis with T. Gondii. The person would likely be very creative and feel particularly inspired by cats, even like they have a psychic connection. In fact it would be a psychic connection.

I love this overlord parasitic puppet master mind controller there my favorite species on the earth XD

It actually bursts from the brain stem- the neck. Scientist have recently discovered like four other strains of this fungi, each of which targets specific types of insects. Its very fascinating.

And there's also Dicrocoelium dendriticum, which is a parasite fluke that lives in cows. Cows poop the eggs with the larva, snails eat the eggs accidentally, then carry them along, then the eggs will exit the snail through its slime, then ants will eat the slime (because they love it) and then the dicrocoelium will take over their brain and make them climb up grass leaves and hold onto those leaves with their jaws so cows will eat them again when they graze.

as long as the cats don't have toxo-carrying rats to eat, they won't poop out toxo for humans to contract

I like how Hank is so angry at these organisms as if they had a nefarious intelligent. "Bastard"!

DAMN, I'M STAYING AWAY FROM MY CAT NOW. DAMN NATURE! YOU SCARY!

There are obviously parallels in human society which reveal certain types of persons and organizations as being parasitic in nature with respect to society at large, and one might say that there are behavioral traits which conduct themselves via their individual host which are likewise parasitic, these may be cognitive, emotional, physico-pathognomic, or any combination of these. I will seek to demonstrate in future videos of my own what are the ontological (spiritual) sorts of parasites.

You could do a video on parasitoidal fungi. They are interesting (and terrifying).

"The crazy, cat lady phenomenon." XD

Tochukaso is a fungus in the real world that is an endoparasitoid that replaces the host tissue and can affect the behavior of its insect host. Paras is an insectoid creature resembling the nymph stage of a cicada, with the unique feature of having mushrooms known as tochukaso growing from its back. ... So At the end even pokemon is subdued by such a parasite

you should have talked about the parasites that uses ants. It's called Cordyceps Fungi, really spooky stuff.

the moment he brings up the cats, my cat leaps into the room.

If you want to know more about toxoplasmosis look up "Stuff you should know" a podcast, has tons of great topics in more depth than these but similar in topic/style. Think they have around 800+ podcasts now, been listening for years.

"Because cats don't eat cat poop" my cats eat each others vomit and each other's hair.

You forgot the Cordyceps fungus, the craziest of them all!

...Oh...Cats...how I love thee and your mind altering shenanigans in order to dominate the will of mankind...Triumph of the Will?

*hank says hairworm* *My hair starts itching*

Cats really don't need any enticement to hunt and eat rats!

I REMEBER LEARNING ABOUT THIS!!!