New Research released from CA Berkley on Monday reveals a scary twist to the scenario of “The Cat and Mouse”. The parasite found in cat’s fecal matter, Toxoplasma, linked to spontaneous abortions in pregnant women and fatal to immune-compromised patients, has an even stranger effect in mice.
Research showed that mice infected by the parasite lose their fear of cats! Some might say that is good for the cat but it is also good for the parasite. By the cat eating the mouse, the parasite will reenter the cat’s intestinal tract where it is the only place the parasite can sexually reproduce, continuing the cycle of infection.
The twist is that the parasite’s ill effects seem to be permanent because the fearless behavior in the mice persists long after the mouse recovers from the flu-like symptoms of toxoplasmosis, and for months after the parasitic infection is cleared from the body. The parasite is no longer in the brain of animals yet research showed some kind of permanent long-term behavior change occurs, even though we do not know what the actual mechanism is…yet!
Wendy Ingram speculates that with further research the parasite indeed damages the smell center of the brain, as well as directly affecting the neurons involved in memory and learning. Ingram became interested in the protozoan parasite after reading about its behavior-altering effects in mice and the implications. These dormant brain “cysts” in immune-compromised people, leads to death, and some preliminary studies suggests the chronicity is linked to schizophrenia and or suicidal behavior.
With the help of UC Berkley professors of molecular and cell biology, Ingram set out three years ago to discover how Toxoplasma affects mice’s hard-wired fear in cats. “The idea that the parasite knows more about our brains than we do, and has the ability to exert desired change in complicated rodent behavior, is absolutely fascinating.”
Currently one-third of the people in the world have been infected with Toxoplasma and probably have dormant cysts in their brains.
Stay tuned…more research to come on this interesting topic. Makes you wonder how little we do know about the brain and the central nervous system.
Thanks Stuart Little