Now many of us think that shows like The Walking Dead are just fictional and can stuff like that can never happen to us in real life right?… Or can it? Around 40% of all life on Earth is parasitic. Parasites are very common, such as the blood sucking leeches and the stomach digestive tapeworms, but there parasites out there far scarier than this; parasites that can control your brain.
Parasites are organisms that live on or inside another organism, feeding off of its resources to survive, and damaging it in the process. They use their host as a source of shelter and food. For example a certain species of parasitic wasps that lay their eggs inside caterpillars, and the babies consume it from the inside out. They do this because inside the caterpillar they are protected from predators. But once they emerge, they are vulnerable. One solution to this problem is to manipulate the host into creating a shelter for the larvae to seek shelter in. The Hymenoepimecis argyraphaga wasp injects its host with a paralytic chemical and then lays its egg in the abdomen of a spider. The spider slowly recovers not knowing that baby wasps are feeding on its blood. When the larvae are ready to pupate, they release a chemical into the spider’s brain, which controls the spider into spinning a cocoon for the larvae. Another example is the Jewel Wasp, which infects cockroaches and hijacks their nervous system, which puts them into a trans. The Jewel wasp releases chemicals that interfere and influence the dopamine and octapine signaling pathways into the brain of the cockroach, which prevents movement. The accuracy of this behavior is incredible, the wasp is able to inject the chemicals right into the right into the sub-oesophageal ganglion of the brain; the part responsible for laying eggs.
Manipulation of neurotransmitters such as serotonin, octaopamine, and dopamine, is a common strategy of parasites to control host behavior. Serotonin is likely to underlie parasitic mind control in many gammerid infections, and dopamine appears to play a key role in T. gondii infections, and is widely spread by parasitic wasps. T. gondii parasite infection has been linked to schizophrenia and suicidal behavior. Toxoplasma gondii controls host behavior through the formation of cysts in the human brain, which secrete the enzyme tyrosine hydroxylase, increasing production of neurotransmitters, which implicit sever human behavior and mental health fluctuations.
As well as injecting neurotransmitters directly into the brain, parasites can accomplish the same behavioral manipulations by influencing the biochemical pathways that produce the neurotransmitting proteins such as dopamine etc. For example gammarid parasites have been found to change the levels of arginine kinase, which is a protein that produces the neurotransmitter nitric oxide. Similar parasites have caused their grasshopper hosts to commit suicide by lunging themselves into streams and lakes.
Although these mind controlling parasites may seem scary or creepy to us, we must remember that were all part of the evolutionary chain, and every living organism must do all it can to survive, and they have been doing so since the beginning of time. Across the world parasites are controlling hosts do as they please. Maybe a zombie apocalypse is around the corner, who knows?