Forbes is a leading source for reliable business news and financial information. Watch news, politics, economics, business & finance on Forbes.com. The Birth of Religion We used to think agriculture gave rise to cities and later to writing, art, and religion. Now the world’s oldest temple suggests the urge to worship sparked civilization. Excelle Sports Travel Talks with Elizabeth Beisel and Allison Schmitt. Mack Horton Has Fan To Thank For Possibly Averting Health Scare. China’s Sun Yang Fathered Child Amid Controversial Career. Watch: Sarah Thomas 56 Hour. How Your Cat Is Making You Crazy. No one would accuse Jaroslav Flegr of being a conformist. Starting in the early 1. And if it was messing with his mind, he reasoned, it was probably doing the same to others. The parasite, which is excreted by cats in their feces, is called Toxoplasma gondii (T. Since the 1. 92. 0s, doctors have recognized that a woman who becomes infected during pregnancy can transmit the disease to the fetus, in some cases resulting in severe brain damage or death. Take a trip around the world with CBC Radio's As It Happens. Take a trip around the world with CBC Radio's As It Happens. Hear from the people at the centre of the stories of the day. From the complex to the weird. Well, actually, Yoshinori Ohsumi has won the prize for his work on autophagy, a cellular process you may have never heard of before. The word means “self eating”, and it’s an important pathway that takes chunks of the. Forbes Welcome page -- Forbes is a global media company, focusing on business, investing, technology, entrepreneurship, leadership, and lifestyle. This channel comprises content supplied by vendors. An introduction to the Physics Package from Maple. A computational tool that can handle a wide range of physics calculations to further decrease. RunwayRiot is the fashion, style, and beauty site for women of all sizes. Shop the Riot for the hottest and latest trends! Millennials have surpassed Baby Boomers as the nation’s largest living generation, according to population estimates released this month by the U.S. Millennials, whom we define as those ages 18-34 in 2015, now. Healthy children and adults, however, usually experience nothing worse than brief flu- like symptoms before quickly fighting off the protozoan, which thereafter lies dormant inside brain cells. He also believes that the organism contributes to car crashes, suicides, and mental disorders such as schizophrenia. When you add up all the different ways it can harm us, says Flegr, . Because he struggles with English and is not much of a conversationalist even in his native tongue, he rarely travels to scientific conferences. And, he believes, his views may invite deep- seated opposition. Psychedelic as his claims may sound, many researchers, including such big names in neuroscience as Stanford. Indeed, recent findings from Sapolsky. Even more amazing is how it does this: the organism rewires circuits in parts of the brain that deal with such primal emotions as fear, anxiety, and sexual arousal. Fuller Torrey, director of the Stanley Medical Research Institute, in Maryland. I think it bears looking at. I find it completely credible. On the verge of killing a dog, bat, or other warm- blooded host, it stirs the animal into a rage while simultaneously migrating from the nervous system to the creature. But aside from rabies, stories of parasites commandeering the behavior of large- brained mammals are rare. The far more common victims of parasitic mind control. A wormlike larva emerges from the egg, and then releases chemicals that prompt the spider to abandon weaving its familiar spiral web and instead spin its silk thread into a special pattern that will hold the cocoon in which the larva matures. Almost 3. 0 years ago, as he was reading a book by the British evolutionary biologist Richard Dawkins, Flegr was captivated by a passage describing how a flatworm turns an ant into its slave by invading the ant. A drop in temperature normally causes ants to head underground, but the infected insect instead climbs to the top of a blade of grass and clamps down on it, becoming easy prey for a grazing sheep. The sheep grazes on the grass and eats the ant; the worm gains entrance into the ungulate. For example, he says, he thought nothing of crossing the street in the middle of dense traffic, . I wondered what was wrong with myself. As it happened, the 6. T. In fact, just as Flegr was arriving, his colleagues were searching for infected individuals on whom to test their improved diagnostic kits, which is how he came to be asked one day to roll up his sleeve and donate blood. He discovered that he had the parasite. After an infected cat defecates, Flegr learned, the parasite is typically picked up from the soil by scavenging or grazing animals. Humans, on the other hand, are exposed not only by coming into contact with litter boxes, but also, he found, by drinking water contaminated with cat feces, eating unwashed vegetables, or, especially in Europe, by consuming raw or undercooked meat. Hence the French, according to Flegr, with their love of steak prepared saignant. The infected rodents were much more active in running wheels than uninfected rodents were, suggesting that they would be more- attractive targets for cats, which are drawn to fast- moving objects. They also were less wary of predators in exposed spaces. Little, however, was known about how the latent infection might influence humans, because we and other large mammals were widely presumed to be accidental hosts, or, as scientists are fond of putting it, a . But even if we were never part of the parasite. But fortunately for him, 3. Czechs had the latent form of the disease, so plenty of students were available . In addition, he used a computer- based test to assess the reaction times of participants, who were instructed to press a button as soon as a white square popped up anywhere against the dark background of the monitor. The subjects who tested positive for the parasite had significantly delayed reaction times. Flegr was especially surprised to learn, though, that the protozoan appeared to cause many sex- specific changes in personality. Compared with uninfected men, males who had the parasite were more introverted, suspicious, oblivious to other people. Infected women, on the other hand, presented in exactly the opposite way: they were more outgoing, trusting, image- conscious, and rule- abiding than uninfected women. The findings were so bizarre that Flegr initially assumed his data must be flawed. So he tested other groups. Again, the same results. Then, in search of more corroborating evidence, he brought subjects in for further observation and a battery of tests, in which they were rated by someone ignorant of their infection status. To assess whether participants valued the opinions of others, the rater judged how well dressed they appeared to be. As a measure of gregariousness, participants were asked about the number of friends they. To test whether they were prone to being suspicious, they were asked, among other things, to drink an unidentified liquid. The results meshed well with the questionnaire findings. Compared with uninfected people of the same sex, infected men were more likely to wear rumpled old clothes; infected women tended to be more meticulously attired, many showing up for the study in expensive, designer- brand clothing. Infected men tended to have fewer friends, while infected women tended to have more. And when it came to downing the mystery fluid, reports Flegr, . They wanted to know why they had to do it. After consulting the psychological literature, he started to suspect that heightened anxiety might be the common denominator underlying their responses. When under emotional strain, he read, women seek solace through social bonding and nurturing. In the lingo of psychologists, they. Perhaps he was looking at flip sides of the same coin. Closer inspection of Flegr. This suggested to him that Toxoplasma might have an adverse impact on driving, where constant vigilance and fast reflexes are critical. He launched two major epidemiological studies in the Czech Republic, one of men and women in the general population and another of mostly male drivers in the military. Those who tested positive for the parasite, both studies showed, were about two and a half times as likely to be in a traffic accident as their uninfected peers. When I met Flegr for the first time, last September, at his office on the third floor of Charles University. But once you get past the riotous red hair, his style is understated. Thin and slight of build, he. As our conversation proceeds, I discover that his latest findings have become. Possibly for that reason, women shown photos of these men rate them as more masculine than pictures of uninfected men. With up to one- third of the world infected with the parasite, Flegr now calculates that T. In addition, reanalysis of his personality- questionnaire data revealed that, just like him, many other people who have the latent infection feel intrepid in dangerous situations. So before coming to Prague, I. It seemed a good time to see what his intuition would tell me. It might just make you a little less introverted. You usually need about 5. The vast majority of people will have no idea they. Many schizophrenia patients show shrinkage in parts of their cerebral cortex, and Flegr thinks the protozoan may be to blame for that. He hands me a recently published paper on the topic that he co- authored with colleagues at Charles University, including a psychiatrist named Jiri Horacek. Twelve of 4. 4 schizophrenia patients who underwent MRI scans, the team found, had reduced gray matter in the brain. After reading the abstract, I must look stunned, because Flegr smiles and says, . When they merged the MRI results with the infection data, however, he went from being a doubter to being a believer. Just as Flegr was embarking on his human trials, Webster, then a freshly minted Ph. D., was launching studies of Toxo- infected rodents, reasoning, just as Flegr did, that as hosts of the parasite, they would be likely targets for behavioral manipulation. She quickly confirmed, as previous researchers had shown, that infected rats were more active and less cautious in areas where predators lurk. But then, in a simple, elegant experiment, she and her colleagues demonstrated that the parasite did something much more remarkable. They treated one corner of each rat. They spent more time in the cat- treated areas. The effect was so specific to cat urine, she says, that . Given the surgically precise way the microbe alters behavior, Webster anticipated that it would end up in localized regions of the brain. But the results defied expectations. Nonetheless, the cysts were most abundant in a part of the brain that deals with pleasure (in human terms, we. Perhaps, she thought, T. The approach brought to light a striking talent of the parasite: it has two genes that allow it to crank up production of the neurotransmitter dopamine in the host brain. Dopamine is a critical signaling molecule involved in fear, pleasure, and attention. Furthermore, the neurotransmitter is known to be jacked up in people with schizophrenia. Antipsychotic medicine designed to quell schizophrenic delusions apparently blocks the action of dopamine, which had suggested to Webster that what it might really be doing is thwarting the parasite. Scientists had already shown that adding the medicine to a petri dish where T. So Webster decided to feed the antipsychotic drug to newly infected rats to see how they reacted. Lo and behold, they didn.
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