The world of psychological research was not ready for the storm it faced in 2011.
Daryl Bem, Emeritus Professor of Psychology at Cornell University, published an article in the Journal of Personality and Social Psychology that provided evidence of an “anomalous retroactive influence of some future event on an individual’s current responses”.
He argued that his nine reported experiments disproved the unidirectional flow of time, and that conscious cognitive and emotional awareness allow us to “feel the future” in a manner that could not be “anticipated through any known inferential process”.
In short, Bem claimed proof that humans were capable of precognition and premonition.
The experiments themselves were certainly eye-catching.
In one, participants were presented with two pictures of curtains on a computer screen. Participants were told that behind one set of curtains was an image and behind the other was a blank wall. The images were sourced from the International Affective Picture System — a bank of photographs designed for use in studies on emotion and attention.
In addition to these, Bem included some images of his own. Or rather, images that he had selected himself. These were erotic pictures that depicted “couples engaged in nonviolent but explicit consensual sexual acts.”
Or the shorthand, porn.
The participants’ task was simple. They had to click on the curtains that hid the picture.
The difficulty of the task should be clear — how often can you predict the result of a coin toss? About half the time. And that is what would be expected in this case if humans were unable to feel the future.
Bem predicted, however, that participants would choose the curtains that hid the erotic images (porn) more than half the time. He reasoned that the ability to anticipate these would confer an evolutionary advantage for reproduction.
Alarmingly, he was correct.
Participants were found to be acting at chance for non-erotic images but were able to find porn like a truffle pig could truffles.
Well, maybe not so much.
When the curtains hid an erotic image, participants clicked on it 53.07% of the time. This might seem fairly small, however, most science operates on ‘statistical tests of significance’ — and even a small effect can be considered significant if it happens often enough. And in this case, Bem found statistically significant evidence that his participants were able to feel the future.
These results were backed up by the other eight experiments in his paper. Bem had provided scientific evidence of what most rational-thinking people considered to be impossible.
Understandably, Bem’s claims — and the evidence that supported them — drew a great deal of attention.
Wiertz, A.J. Nude behind the curtain. Wiertz Museum. https://commons.wikimedia.org/wiki/File:Nude_behind_the_curtain.jpg
Bem’s research is an important chapter in the history of parapsychology — a field dedicated to the study of certain unusual events associated with the human experience. The Parapsychological Association (PA) defines parapsychological research as concerning extrasensory perception (ESP), mind-matter interactions, and “survival” experiences (i.e. hauntings, reincarnations, near-death-experiences, etc).
PA state that parapsychological researchers are not simply researchers of “anything paranormal” — specifically precluding “astrology, UFOs, searching for Bigfoot, the Loch Ness monster, paganism, Satanism, vampires, alchemy, or witchcraft” from their work.
Bem is an example of a psi researcher. Psi is defined by the PA as a neutral term for ESP and mind-matter related phenomena. Bem proposed that his research was an example of precognition, a form of ESP. However, he did acknowledge that it might instead represent a mind-matter interaction. He suggested that participants might have been responsible for influencing the output of the random number generator responsible for assigning the placement of the erotic images.
It is commendable to approach research with an open mind.
Parapsychology is widely considered to be a pseudoscience. Critics point out that its claims violate well-established laws of physics and that it has provided precious little evidence in order to overturn them. They accuse definitions used in the field of being at best imprecise and at worst obfuscatious.
Parapsychology is criticised on the foundations of its methods. Researchers continue to look for paranormal effects, despite over 150 years of documented failures. Critics suggest that parapsychological researchers are unwilling to accept a null result — that failed experiments are ignored rather than accepted.
Most parapsychological research is published in niche journals, the quality of which has often been questioned. Many sceptics point out that parapsychological research is rife with errors, bias, and generally questionable research practices.
And this is perhaps what was most compelling about Bem’s research.
Bem’s work met the accepted standard of scientific rigour — and as such passed the peer-review process to be published in a journal with a good reputation. Bem himself had an established career as a mainstream psychologist before he focused on parapsychological research. It was not so easy to dismiss his experiments as the workings of a crackpot on the fringes.
The unprovable had finally been proved. ESP had been demonstrated in laboratory conditions. The mysteries of the universe had been revealed as more mysterious than we had thought. There was no more quibbling with the facts.
Well, not quite.
Lacey, C. Thoughtograph, or Psychic Photograph (1894-98). The Metropolitan Museum of Art, New York. https://images.metmuseum.org/CRDImages/ph/original/DP275696.jpg
If the wider research world had to accept Bem’s results, it was not going to do so without a fight.
And so critics began to analyse his work. There were accusations of “dirty test tubes” — experimental malpractice or corner-cutting that paved the way for questionable results. Further arguments were made that his statistical approach was lacking. Re-examination of his data suggested that his findings weren’t as significant as he had claimed. And so on.
Ultimately the key to scientific research is replication. It is important that an effect is not only found once, but that it can be found time and time again. In his paper, Bem welcomed attempts to replicate his research. He stood by his work and his findings.
And so the replications began. And they found what most people expected — no evidence of precognitive abilities.
But the story doesn’t end quite there.
Bem’s research is not unique in that it could not be reliably replicated. The wider research world was at that time coming to terms with the ‘replication crisis’ — a widespread failure to replicate experiments, including those that were more palatable on the surface.
This is a problem that has affected many areas of science, including chemistry, biology, and physics. However, it has been a particular problem in psychology. With many celebrated effects (such as the ‘power pose’) falling victim to replication failures.
Dirty test tubes, it turns out, might be found in many places.
One particular pressure is publication bias. Journals prefer to publish work with positive results — that is, work that ‘finds’ something. Careers are largely built on publication record, and the pressure to publish is strong. This can lead to questionable research practices being rewarded, perpetuating a broken system.
A proposed solution to this problem is pre-registering studies with a journal. Researchers submit their method and rationale prior to collecting data. If the journal considers the research question to be compelling and the method to be strong, they commit to publishing the work. Regardless of how the results turn out.
Bem’s paper has caused a monumental shift in modern scientific thinking. Albeit, due to the effects it has had on improving standards and approaches in research methodology. As it stands, no convincing evidence has been provided of psi phenomena.
Intentionally or otherwise, Bem’s work held up a mirror to psychological research. It demonstrated that issues were present within the scientific process, and great efforts have been made towards addressing these.
There is one final study to consider.
A replication of Bem’s hidden picture experiment has been pre-registered in Royal Society Open Science. You can read the manuscript now, complete with its delete-as-appropriate conclusions, prior to data collection.
The authors clearly do not expect a positive result. If they find one, they will report that it does not “confirm, nor contradict the existence of ESP in general”. Instead, they will conclude that their and Bem’s findings cannot be explained by known experimental biases. Future research will then be needed to explain the causal mechanism behind the results.
I do not expect that this conclusion will survive to the final manuscript. But only time will tell.
Unless of course, I am wrong. In which case we have a lot more explaining to do.
Alcock, J. (2011). Back from the future: Parapsychology and the Bem affair. Skeptical Inquirer, 35(2), 31-39.
Baker, M. (2016). 1,500 scientists lift the lid on reproducibility. Nature News, 533(7604), 452.
Bem, D. J. (2011). Feeling the future: experimental evidence for anomalous retroactive influences on cognition and affect. Journal of personality and social psychology, 100(3), 407.
Engber, D. (2017). Daryl Bem proved ESP is real: Which means science is broken. Slate.
Kekecs, Z., Aczel, B., Palfi, B., Szaszi, B., Szecsi, P., Zrubka, M., ... & Dubrov, D. (2019). Raising the value of research studies in psychological science by increasing the credibility of research reports: The Transparent Psi Project-Preprint. PsyArXiv. https://psyarxiv.com/uwk7y/
Parapsychological Association (2015) Frequently Asked Questions. https://www.parapsych.org/section/36/frequently_asked_questions.aspx
Rabeyron, T. (2020). Why most research findings about psi are false: the replicability crisis, the psi paradox and the myth of Sisyphus. Frontiers in Psychology, 11, 2468.
Reber, A. S., & Alcock, J. E. (2020). Searching for the impossible: Parapsychology’s elusive quest. American Psychologist, 75(3), 391.
Rouder, J. N., & Morey, R. D. (2011). A Bayes factor meta-analysis of Bem’s ESP claim. Psychonomic Bulletin & Review, 18(4), 682-689.
Cover photo: Robert Sheaffer, CC BY-SA 3.0 <https://creativecommons.org/licenses/by-sa/3.0>, via Wikimedia Commons. https://upload.wikimedia.org/wikipedia/commons/2/27/DarylBem.jpg