The illusory truth effect

Research has revealed that there is a colony of cockroaches on the moon, the descendants of the cockroach that went in Apollo 11. You don’t believe me? Didn’t you read it in the papers?  A magazine article? On WhatsApp? It is probably true, otherwise why would so many people write about it.

That is how the human mind works. When a person hears the same information several times, no matter how absurd it is, the mind starts convincing us of its truthfulness. WhatsApp forwards are a classic example of this, where, if misinformation is circulated a number of times, it takes on the status of truth. This is called the illusory truth effect.

Researchers, led by Liza Fazio at Vanderbilt University, have shown that when one hears something for the second or third time, the brain responds faster to it. This faster response is wrongly considered by the person to be a signal for the information being true. Gord Pennycook, a psychologist at Yale University, studies the spread of misinformation, and has shown through experiments that when participants were told something and then told the same thing the next day their familiarity with the news led them to rate it as being true. The frustrating truth about the illusory truth effect is that it happens to us unthinkingly. Even people who are knowledgeable about topics can fall prey to it, specially if it is reinforced by an equally lazy “mentor” type like a teacher/doctor/parent. In 2015, Fazio and co-authors published a paper that found that prior knowledge about a topic doesn’t inoculate you to the effect.

The illusory truth effect has been studied for decades. Typically, experimenters in these studies ask participants to rate a series of trivia statements as true or false. Hours, weeks, or even months later, the experimenters bring the participants back again for a quiz. On that second visit, some of the statements are new and some are repeats. And it’s here that the effect shows itself: Participants are reliably more likely to rate statements they’ve seen before as being true — regardless of whether they are. When you’re hearing something for the second or third time, your brain becomes faster to respond to it. “And your brain misattributes that fluency as a signal for it being true,” says Fazio “The more you hear something, the more you’ll have this gut-level feeling that maybe it’s true.”

People often pass on information without validating its source. The internet is full of amazing seeds that make you lose weight immediately, miracle hair oils and, of course, cancer cures. Studies have shown that fake information tends to circulate much faster than real information, and is remembered and believed by people for a longer period of time. This is especially true when the information encountered is in line with our beliefs or desires. E.g. immigrants are the cause of all social and economic issues, women are bad drivers, the British are responsible for all of India’s problems, drugs must be tested on animals before being ready for human consumption and so on.

Does that last one sound familiar? Many of you might be thinking “But of course drugs have to be tested on animals. Scientists have been doing so for 100 years, so it must be necessary.”

While we expect politicians to tell lies, no one exaggerates and twists truth as much as the so called scientist. 100 years later we are no closer to even discovering what causes cancer – much less what cures it. But tests on over 50 million animals go on annually and, in order to justify this , things are periodically put into the papers that a cure is just round the corner. We have not even been able to deal with teenage acne, rheumatoid arthritis, diabetes, obesity, Alzheimer's – all of which are on the rise – but scientific misinformation goes on to keep us from questioning the huge amounts of money given by governments and charities to pay salaries.

Animals are completely different from humans –anatomically, genetically and metabolically – even their basic cellular structures. So, even if a particular medicine or procedure is effective or safe on an animal, it may have adverse effects on humans. Even more importantly, human diseases occur naturally, while experiments on animals involve an artificial re-creation of the disease in the animal, which is inevitably inaccurate. Giving a rat diabetes, by destroying its pancreas and then injecting it with drugs to see its effect on the disease, has no bearing at all on the human condition. Rats have been genetically modified to be cancer ridden. Not one experiment on them has shown the way forward to curing the disease in humans.

Data derived from testing on animals cannot be accurately extrapolated to humans. The American Federal Agency for Food and Drug Administration has confirmed that nine out of ten drugs, shown to be successful in animal tests, have failed in human trials. E.g. a drug named Cylert was passed through animal tests and proposed to treat Attention Deficit Hyperactivity Disorder. However, when administered to children it had disastrous effects, causing liver failure in 13 children, 11 of whom either died or had to undergo liver transplants. Vaccines tested on animals pass the tests. The same vaccines given to children in India have caused so many recent deaths.

Clearly, animal testing is not just a waste of time and money, it also has the potential of huge damage to humans.

The flipside is equally dangerous – there are drugs that fail animal testing but could potentially be very useful for humans. E.g. the path-breaking drug penicillin was found to be ineffective on rats and rabbits and had a deadly effect on guinea pigs and hamsters. Scientists were discarding it. However, since passing animal testing was not considered mandatory at that time, it was tested directly on humans and opened up the entire field of antibiotics for human welfare. Because the scientists are so stubborn about animal testing, there may be a number of potential cures that have never reached us.

Despite common sense telling us that a rat is not a monkey is not a human, animal testing has been mandatory for decades and is allowed, even encouraged, by non scientific people who falsely believe it to be useful. This is a real life example of the illusory truth effect.

New technologies have now been developed, which are more effective ways of predicting effects on humans. We have mass spectrometry, genome mapping, innovative imaging techniques and highly developed computer models capable of simulating parts of the human body, to name just a few. In-vitro experiments, using human blood and tissue to determine toxicity. have 2-3 times more accurate results than animal testing. Research on humans, such as clinical studies by analyzing a patient’s condition and responses to treatments, provide vital information, and have given us treatments for childhood leukaemia, thyroid disease, current HIV and AIDS therapies and many more. Similarly, autopsies have given critical information about human bodies and their interaction with a variety of drugs and procedures.

Even though we encounter new and valid information, we continue supporting the pointless practice of animal testing, under the false belief that it is useful to medical research. Scientists, universities and big pharmaceutical companies have been perpetuating this belief systematically for years, as it helps them accumulate huge research funding and cover up their inaction and inefficiency. Companies that earn millions selling harmful products like cigarettes, sugar, colas, genetically modified foods, polluting cars etc., benefit by influencing research and hiding the real effects of their products on people by saying that their products are safe based on ‘successful’ animal tests.

This age, more than any other, is, on one hand, victim to an overload of information, giving us little time to go into details. On the other, it is easy to expose fraud which has been posing as science. I would encourage you to read up on the failure and potential disasters of animal testing, because it is not about the animal’s life: it is about yours.

Maneka Sanjay Gandhi
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*Proper wildlife rehabilitation is an extremely biologically and ecologically responsible attitude toward all living things.*