bogleech:

Well, I guess I should clarify that “mind controlling” parasites are usually a misnomer and a little hyperbolic anyway.

It was believed Cordyceps fungi affected their host’s brains until recently, but then it was proven that they leave the brain entirely intact. Instead, they control the insect’s actual muscles. This is again only possible because an insect has only a couple simple, microscopic muscle strands though, like a few “strings” to manipulate, rather than a larger mammal’s relatively GIGANTIC mass of millions and millions of cells forming thousands of individual muscles.

Parasites that truly alter the host’s mind are only doing so by damaging a single part of it. Target the right point in a mouse’s brain and you just eliminate its fear of predators. Take out certain points in a small fish and you cause it to swim closer to the water’s surface instead of avoiding sea birds.

So what manipulative parasites really do is give the host a single new behavioral “quirk.” It’s pretty much an organism giving another organism a simple mental illness symptom.

The realest equivalent we could ever have to something like Cordyceps or Leucochloridium in humans would probably be indistinguishable from someone gaining a sudden stim behavior or obsessive compulsion and probably no big deal to live with if so many people already do and it still doesn’t turn into an apocalypse or nothin

Toxoplasma, a parasite that makes rats unafraid of predators and is often found in used cat litter, makes infected humans more reckless and may be linked to mental illness. There are estimates that something like 30% of the human population is infected. We certainly haven’t had any sort of apocalypse.