|
Tag: deception
Evidence that placebos could work even if you tell people they’re taking placebos
In many medical studies, even people who take “fake” treatments, such as sugar pills with no active ingredients, can still feel better. These are the puzzling “placebo effects”. They are common, diverse and powerful and they raise an interesting ethical question – can doctors justifiably prescribe placebos to their patients? The standard answer is no. Doing so patronises the patient, undermines their trust, and violates the principles of informed consent. It compromises the relationship between doctor and patient. At worst, it could do harm.
But many of these arguments are based on the idea that placebo effects depend on belief; people must expect that treatments will work in order to experience any benefits. For a doctor to prescribe a placebo, they’d need to deceive. But according to Ted Kaptchuk from Harvard Medical School, deception may not be necessary. In a clinical trial, he found that patients with irritable bowel syndrome (IBS) felt that their symptoms improved when they took placebo pills, even if they were told that the pills were inactive.
Fabrizio Benedetti, a placebo researcher at Turin Medical School who wasn’t involved in the study, says, “Although several studies suggested that placebos can be equally effective without deception, this is the first rigorous study that provides scientific evidence for this.”
Referring to an earlier study published in the British Medical Journal, he says, “We did the study because we knew that physicians were giving placebo to patients secretly without informed consent. Our study was designed to test whether placebo effects could be harnessed without this secret deception.”
The signature of the bluffing brain
The best poker players are masters of deception. They’re good at manipulating the actions of other players, while masking their own so that their lies become undetectable. But even the best deceivers have tells, and Meghana Bhatt from Baylor University has found some fascinating ones. By scanning the brains and studying the behaviour of volunteers playing a simple bargaining game, she has found different patterns of brain activity that correspond to different playing styles. These “neural signatures” separate the players who are adept at strategic deception from those who play more straightforwardly.
Robots evolve to deceive one another
In a Swiss laboratory, a group of ten robots is competing for food. Prowling around a small arena, the machines are part of an innovative study looking at the evolution of communication, from engineers Sara Mitri and Dario Floreano and evolutionary biologist Laurent Keller.
They programmed robots with the task of finding a “food source” indicated by a light-coloured ring at one end of the arena, which they could “see” at close range with downward-facing sensors. The other end of the arena, labelled with a darker ring was “poisoned”. The bots get points based on how much time they spend near food or poison, which indicates how successful they are at their artificial lives.
They can also talk to one another. Each can produce a blue light that others can detect with cameras and that can give away the position of the food because of the flashing robots congregating nearby. In short, the blue light carries information, and after a few generations, the robots quickly evolved the ability to conceal that information and deceive one another.
Their evolution was made possible because each one was powered by an artificial neural network controlled by a binary “genome”. The network consisted of 11 neurons that were connected to the robot’s sensors and 3 that controlled its two tracks and its blue light. The neurons were linked via 33 connections – synpases – and the strength of these connections was each controlled by a single 8-bit gene. In total, each robot’s 264-bit genome determines how it reacts to information gleaned from its senses.
In the experiment, each round consisted of 100 groups of 10 robots, each competing for food in a separate arena. The 200 robots with the highest scores – the fittest of the population – “survived” to the next round. Their 33 genes were randomly mutated (with a 1 in 100 chance that any bit with change) and the robots were “mated” with each other to shuffle their genomes. The result was a new generation of robots, whose behaviour was inherited from the most successful representatives of the previous cohort.
Orang-utans use leaves to lie about their size
You’ll sometimes hear people lowering their voices to make themselves sound tougher or more commanding. We’re not the only ones – it seems that our close relatives, the orang-utans, pull the same trick, and they use tools to do it. Madeleine Hardus from the University of Utrecht has found preliminary evidence that young orang-utans use leaves for deception, in order to make lower-pitched calls that seem to come from a much larger animal.
While many animals are accomplished tool-users, most use their utensils to find food. A few populations of orang-utans, living in Borneo, are the only animals known to use tools to change the nature of their calls, much like humans use loudspeakers or microphones.
Their tools are leaves, and they’re used in the context of a specific call known as the kiss-squeak. It’s made by orang-utans when they are disturbed by predators like humans, tigers or snakes, or even by rivals of their own species. You can do it yourself: purse your lips together and suck air in sharply to produce a squeaky kissing sound. All orang-utans do it and because these apes are largely solitary, the calls are unlikely to be alarms – they’re probably deterrents instead.
Hardus spent over two years recording over 1,000 kiss-squeaks from 23 wild orang-utans and found that the pitch of the squeaks reflect the size of the animal. Calls made by adult females have a higher maximum frequency than the large elder males, while those made by immature youngsters are the highest of all. This means that the calls could potentially provide information to a canny listener about the size and power of the caller.
To some extent, orang-utans can fake a deeper call by placing a hand in front of their lips, but leaves are the greatest equaliser of all. By stripping a bundle of leaves from a twig and holding them in front of their mouths, even a small adolescent can drop the pitch of its call to below the level of a large unaided male.
DISCOVER's Newsletter
Sign up to get the latest science news delivered weekly right to your inbox!
