There is a whole industry of social psychologists specialising in – and getting funded for – studying “social priming”. The more astonishing or contra-intuitive the result the more attention, the more publicity and the more funding the researcher seems to get. But it seems that many (maybe most) of these study results are irreproducible. It is not implausible that priming does (should) affect subsequent behaviour but social psychologists seeking fame through astonishing results (often, it seems, made-up results) have not helped their own cause. The list of questionable “social priming” results is getting quite long:
- Thinking about a professor just before you take an intelligence test makes you perform better than if you think about football hooligans.
- people walk more slowly if they are primed with age-related words
- A warm mug makes you friendlier.
- The American flag makes you vote Republican.
- Fast-food logos make you impatient
- lonely people take longer and warmer baths and showers, perhaps substituting the warmth of the water for the warmth of regular human interaction
Attention-grabbing results seem to be common among social psychologists of all kinds. A made-up result which says that “the smarter a man is, the less likely he is to cheat on his partner” generates the expected headlines and spots on TV talk shows. Diedrik Stapel made up data to prove that “meat eaters are more selfish than vegetarians”. Dirk Smeesters claimed that “varying the perspective of advertisements from the third person to the first person, such as making it seem as if we were looking out through the TV through our own eyes, makes people weigh certain information more heavily in their consumer choices” and that “manipulating colors such as blue and red can make us bend one way or another”. But Smeesters too has now admitted cherry picking his data. A raft of retractions followed and is still going on.
A paper published in PLoS ONE last week1 reports that nine different experiments failed to replicate this example of ‘intelligence priming’, first described in 1998 (ref. 2) by Ap Dijksterhuis, a social psychologist at Radboud University Nijmegen in the Netherlands, and now included in textbooks.
David Shanks, a cognitive psychologist at University College London, UK, and first author of the paper in PLoS ONE, is among sceptical scientists calling for Dijksterhuis to design a detailed experimental protocol to be carried out indifferent laboratories to pin down the effect. Dijksterhuis has rejected the request, saying that he “stands by the general effect” and blames the failure to replicate on “poor experiments”.
An acrimonious e-mail debate on the subject has been dividing psychologists, who are already jittery about other recent exposures of irreproducible results (see Nature 485, 298–300; 2012). “It’s about more than just replicating results from one paper,” says Shanks, who circulated a draft of his study in October; the failed replications call into question the underpinnings of ‘unconscious-thought theory’. ….
….. In their paper, Shanks and his colleagues tried to obtain an intelligence-priming effect, following protocols in Dijksterhuis’s papers or refining them to amplify any theoretical effect (for example, by using a test of analytical thinking instead of general knowledge). They also repeated intelligence-priming studies from independent labs. They failed to find any of the described priming effects in their experiments. ……
……. Other high-profile social psychologists whose papers have been disputed in the past two years include John Bargh from Yale University in New Haven, Connecticut. His claims include that people walk more slowly if they are primed with age-related words.
Bargh, Dijksterhuis and their supporters argue that social-priming results are hard to replicate because the slightest change in conditions can affect the outcome. “There are moderators that we are unaware of,” says Dijksterhuis.
But Hal Pashler, a cognitive psychologist at the University of California, San Diego — a long-time critic of social priming — notes that the effects reported in the original papers were huge. “If effects were that strong, it is unlikely they would abruptly disappear with subtle changes in procedure,” he says. ….
This fall, Daniel Kahneman, the Nobel Prize-winning psychologist, sent an e-mail to a small group of psychologists, including Bargh, warning of a “train wreck looming” in the field because of doubts surrounding priming research. He was blunt: “I believe that you should collectively do something about this mess. To deal effectively with the doubts you should acknowledge their existence and confront them straight on, because a posture of defiant denial is self-defeating,” he wrote.
……. Pashler issued a challenge masquerading as a gentle query: “Would you be able to suggest one or two goal priming effects that you think are especially strong and robust, even if they are not particularly well-known?” In other words, put up or shut up. Point me to the stuff you’re certain of and I’ll try to replicate it. This was intended to counter the charge that he and others were cherry-picking the weakest work and then doing a victory dance after demolishing it. He didn’t get the straightforward answer he wanted. “Some suggestions emerged but none were pointing to a concrete example,” he says.
Social psychology and social psychologists have some way to go to avoid being dismissed out of hand as charlatans.
