Hahahahaha! A psychologist claims evidence for ESP! Oh, those scientists and their April Fools’ jokes’–what? He appears to be serious? He’s published in a reputable psychology journal?
Well, screw that for a lark.
Dr. Daryl J. Bem, a fairly eminent experimental psychologist who should bloody well know better, has published “Feeling the Future: Experimental Evidence for Anomalous Retroactive Influences on Cognition and Affect” in the Journal of Personality and Social Psychology (which should also know better).
I’m not going to attempt to touch the statistical evidence, since folks who know a lot more than I do have a comment in the same issue. (In case you’re interested, they say “We reanalyze Bem’s data with a default Bayesian t test and show that the evidence for psi is weak to nonexistent.” Oh, snap!)
But believe me, there’s plenty to mock. In the first experiment, Bem claims participants predicted in advance when an “erotic image” was going to appear on one of two screens.
The presentiment studies provide evidence that our physiology can anticipate unpredictable erotic or negative stimuli before they occur. Such anticipation would be evolutionarily advantageous for reproduction and survival if the organism could act instrumentally to approach erotic stimuli and avoid negative stimuli.
Seriously? How can he even type that with a straight face?
Here’s the thing my dad and I hashed out: What the hell good is a slight (very, very slight) increase in ability to anticipate something erotic if it’s only noted by the unconscious mind? If you’re gonna be deciding whether or not to have sex, you might want to know about it. You can only get so far on your hormones, dude.
And then things get sillier:
Across all 100 sessions, participants correctly identified the future position of the erotic pictures significantly* more frequently than the 50% hit rate expected by chance…. In contrast, their hit rate on the nonerotic pictures did not differ significantly* from chance…. This was true across all types of nonerotic pictures.
(*Of course, that’s statistical significance not significance in the sense normal people mean. The actual numbers? Small.)
I banged my head against this until I realized what was bugging me: Participants (keep in mind these are college students) were apparently able to predict porn might be coming, but couldn’t accurately predict anything else.
As far as I can tell, what Dr. Bem’s experiment has proved is that college students looking at pictures frequently expect porn. Quelle surprise! (As my mother said when I told her this.)
Seriously, though, with nothing but aggregate numbers to look at, it seems to me that once people saw porn once, they’d anticipate it somewhat more often than anything else. And just by chance, if you’re more likely to anticipate the porn, you’re going to be right more often.
And you’ll note that they weren’t right as often about anything else. But that doesn’t make a whole hell of a lot of sense if we’re talking about some kind of “extrasensory perception.” Because if your brain is (occassionaly!) capable of knowing that the porn is coming, wouldn’t it conversely be able to tell you that porn wasn’t coming? Don’t those two sort of…go together?
Okay, but that’s just experiment one. Maybe the others make more sense, right?
Experiment two used positive and negative subliminal images flashed on a screen. Participants chose between a picture and its mirror image and if they expressed a preference for the one the computer decided to choose, they were shown a positive subliminal image (not described in the article), but if they expressed a preference for the other picture, they were shown a negative subliminal image (also not described).
The theory is that participants were able to psychically guess which image they should choose in order to get the positive stimulus rather than the negative one. But participants weren’t told about the positive and negative images or what might cause them to be exposed to either one, so how the hell would they know what to do in order to get the supposed results? Apparently they were also psychic enough to read the experimenters’ minds? Wow. Now that would impress me.
Subsequent experiments were similar: College students were shown two pictures and instructed to pick the one they preferred, then the computer chose one of the two, and if they student picked the same one as the computer, it was considered a hit.
By the way, did I mention that “on trials with negative picture pairs, participants preferred the target significantly more frequently than the nontarget,… On trials with erotic picture pairs, participants preferred the target significantly less frequently than the nontarget”?
Hmmm. Bem doesn’t actually say, but it sounds to me like when there was porn involved, the college students preferred the porn, which completely overset his results. ‘Nuff said.
Experiment eight was also rather amusing, in which students were tested on their ability to recall a list of words, then were given some of those words to practice and repeat. The idea was to test whether they would retroactively remember those words better for having practiced them.
No, you didn’t misread that. “The results show that practicing a set of words after the recall test does, in fact, reach back in time to facilitate the recall of those words.” I’ll give you some time to hit your head against a wall before we continue.
The article ends, as these things often do, with a discussion section. This section, as all articles on psi phenomena must, mentions quantum mechanics.
Those who follow contemporary developments in modern physics, however, will be aware that several features of quantum phenomena are themselves incompatible with our everyday conception of physical reality.
In other words, “I have no idea how quantum physics works and I have no idea how my proposed ESP works, so it must be the same kind of thing!” Not so much.
Look, I understand there are cases where a small change in ability can confer a large evolutionary advantage. But even if Bem’s results are absolutely true and correctly interpreted, the ability to very, very occasionally unconsciously predict seeing sexual activity or a picture that gives you a negative emotion doesn’t strike me as useful. And why would it have remained unconscious, where it doesn’t do us any particular good?
The best counterargument, of course, is that something doesn’t have to be evolutionarily advantageous to exist, it just has to not be evolutionarily disadvantageous. And that’s true. I can’t imagine that the ability to occasionally know you’re going to see something unpleasant or sexy would make you less able to reproduce. But that’s not an argument that’s going to make me see very unlikely psychic phenomena in very tiny results.
Dr. Bem says that just because we don’t know a workable mechanism for ESP, we shouldn’t immediately toss out all evidence of it. Which sounds logical and rational, but I’ve always believed that extraordinary claims require extraordinary evidence.
And lemme tell ya: This ain’t it.
_____________________________Mara Greengrass Blogger, Mama Mara t
Conflict of interestmI’m an independent contractor working for the association that publishes this journal, but they would be horrified if anyone suggested I was speaking on their behalf.
Editorial Materials and methodsmI used my laptop, my outrage, and my father’s brain in writing this. My method consisted of me reading bits of this aloud to my parents, followed by my hollering “What the FUCK?” and then looking around to make sure my kids weren’t listening. This post also appears on my blog.