Williams: Bem Precognition Post 1

Daryl Bem’s Precognition Experiments: Can We Subtly “Feel the Future?”

Bryan Williams

University of New Mexico In terms of the way it is thought to act in the course of our waking, everyday lives, precognition is often seen as a kind of psychic “sense of foreboding,” a subtle intuitive sense, feeling, or impression warning us about events in the future that may come to affect our lives. This sense, feeling, or impression often seems to come out of nowhere for no apparent reason, and can leave us with the strong conviction that something is about to happen to us and/or someone we care about. An illustrative example comes from a woman who reported her precognitive experience to the Rhine Research Center (RRC) in North Carolina, and which was subsequently published in the book The Gift, co-authored by the RRC’s executive director, Dr. Sally Rhine Feather (Feather & Schmicker, 2005). In the account of her experience, the woman stated:

My husband and I were on an excursion boat. We had saved and planned for the ride, and the gangplank was already up when I got “butterflies.” Our two-month-old daughter was with us. I told my husband I was getting off the boat. He thought I was crazy. I said he could stay, but I had to get off, and I asked the men to put the gangplank down. … The next news bulletin we heard said that there was a collision, and a freighter had hit the excursion boat we had been on. Within fifteen minutes the excursion boat sunk, though all aboard were rescued (pp. 64 – 65).

Accounts of many similar kinds of precognitive experiences are presented in the book, as well as in the recent book The Power of Premonitions by physician Larry Dossey (2009). Making up roughly 13 percent of all the types of precognitive cases that have been reported to the RRC,1 such experiences are suggestive of momentary mind-body feelings of anticipation manifesting just on the edge of conscious awareness. Can we really, in some instances, subtly “feel the future?” Some experiments performed over the past few decades seem to offer evidence suggesting that we can. These include a series of nine experiments performed by social psychologist Daryl Bem (2011a) and his research team at Cornell University, which were just published in the Journal of Personality and Social Psychology, a prominent mainstream publication.2 But before focusing specifically on these experiments, let us take a brief look at some of the others as a prelude: In the experiments on “presentiment” initiated by Dean Radin (1997b, 2004) of the Institute of Noetic Sciences in California, volunteers were randomly shown affective and neutral pictures on a computer screen while the electrical activity in the nerves of their skin (called electrodermal activity, or EDA) was monitored. Affective pictures show things that tend to arouse a strong emotional response in us, whether negative (e.g., violent acts, mutilated bodies, threatening animals) or positive (e.g., erotic images). In contrast, neutral pictures show things that tend to be relatively “bland” and stir little emotion, such as landscapes, household items, and fruit. Radin’s results indicated that, in the few seconds before they were shown an affective picture, the volunteers’ EDA had significantly increased (as compared to the EDA before being shown a neutral picture, which was lower). This suggests that, even before seeing the affective picture, the volunteers had shown a subtle emotional “jump” in anticipation of its appearance, which became known as the presentiment (“pre-feeling”) response.3 Similar results were obtained in follow-up

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studies conducted in two laboratories using different equipment and software (Bierman & Radin, 1997, 1999), countering the argument that the results were due to technical glitches. Instead of using affective pictures, other researchers have tried to evoke a presentiment response in volunteers by playing loud startle sounds (e.g., alarms, sirens, gunshots) into their ears at random times. And just as with the pictures, a significant increase in the volunteers’ EDA was seen in the few moments before they heard the sounds (May et al., 2005; Spottiswoode & May, 2003).4 If subtle precognitive effects like presentiment really do represent a kind of psychic “sense of foreboding” about the future, then they would certainly seem to be useful for our survival. And if that is so, then it is natural to ask, why are they often so subtle that we don’t even notice them? One possible answer could be that these effects are embedded within our normal behavior, and as a result, they are effectively “masked” by it. As parapsychologist Richard Broughton (2006) has stated:

An evolutionary view of these [precognitive effects] would suggest that the underlying system is tightly integrated with all our other information processing and decision making abilities so that it may not be apparent to a person if the information came from the future. It may seem like a hunch, or an intuition (p. 331).

If this suggestion has merit, then it might go a long way towards explaining why the waking intuitive type of precognition case is so much rarer than the dream type (see Note 1). There are currently two ways in which we can basically explore this suggestion. One way is to search for presentiment effects in mainstream psychophysiological studies of emotion and decision making. Dick Bierman (2000) of the University of Amsterdam made a preliminary effort to do this by reanalyzing the data from two studies. In one study (Bechara et al., 1997), researchers at the University of Iowa had monitored peoples’ EDA while they made risky decisions in a gambling task. In the other study (Globisch et al., 1999), a group of European researchers monitored the startle reflex responses of people afraid of snakes or spiders whenever pictures of the feared animal were flashed before them (accompanied by loud startle sounds) at random times. As one might expect, the people in these two studies showed large EDA increases after learning that they had made a bad decision, or after being exposed to the picture of the feared animal, respectively. However, Bierman’s analysis showed that, in the few seconds preceding these outcomes, the people had also shown small but significant EDA increases (akin to presentiment), as if they were already showing subtle emotional responses before the outcomes had even occurred. Later in his own study, Bierman found similar presentiment-like EDA increases displayed by volunteers before they made “errors” (in the form of incorrect choices) in learning a basic grammar task using symbols as “words” (Bierman et al., 2005). The other way is reflected in the approach taken by Bem in his series of nine reported experiments: to look for precognition in reversed forms of well-known psychological effects related to emotion and cognitive thought. The rest of this post will be devoted to a basic summary of these experiments and their results.5

Precognitive Approach and Avoidance The first experiments described by Bem (2011a) in his latest article were initially reported at the 2008 Convention of the Parapsychological Association (PA) (Bem, 2008), and are related to the idea that we tend to approach things that seem positive and beneficial to us, while avoiding things that seem negative and threatening. The experiments were essentially designed to explore

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whether or not we are able to anticipate the appearance of these things in the future through precognition. Let’s see how. Experiment 1: Precognitive Detection of Erotic Pictures To explore the idea of approaching positive things, Bem and his team decided to use something that can be considered positive in a titillating way: pictures of erotic scenes. At its heart, this experiment consisted of a basic two-choice precognition test that is conceptually consistent with many earlier kinds of tests,6 and is useful for the simplicity of its design. An illustration of the test is shown in Figure 1 below. During the test, a participant is seated before a computer screen. Following a short relaxation period, the participant completes a series of 36 individual test trials. At the beginning of each trial, the participant is shown digital images of two curtains side-by-side (Step 1 in Figure 1), and asked to choose the curtain that he or she thinks will soon be selected to have an erotic picture behind it (Step 2). Once the participant has chosen a curtain, the computer randomly selects one of the curtains to be the precognitive target (i.e., the one that will have the picture behind it) (Step 3). The computer then opens the curtain and reveals what it is behind it to the participant. If the curtain that the participant chose was the target, then the trial is considered a success (a “hit”), and the erotic picture behind the curtain is shown (Step 4). Otherwise, there is only a blank screen behind the curtain. The process then begins again at Step 1 for the next trial. The main thing to keep in mind here in terms of precognition is that the computer selects the target curtain only after the participant has chosen a curtain.

1. Participant is shown two 2. Participant is asked to 3. Computer randomly 4. If the curtain that thecurtain images side-by-side choose which curtain will selects one curtain as participant chose is the

have the picture behind it the target (will have target, computer showspicture behind it) picture to participant

Figure 1. A basic illustration of the experimental test for the precognitive detection of erotic pictures (Bem’s Experiment 1). The steps in a successful test trial (a “hit”) are illustrated here; see text. With two curtains to choose from, the probability of getting a hit is 1 in 2 (i.e., 50/50). Thus, the average hit rate expected by chance over the course of the test is 50%. The precognition hypothesis would predict that the participant is able to obtain a significantly higher percentage of hits. In addition to the erotic pictures, Bem and his team also used negative and neutral pictures on some of the test trials. They compared the hit rate on these “non-erotic” (control) trials with the hit rate on the erotic trials to see “… whether there is something unique about erotic content in addition to its positive valence and high arousal value” (Bem, 2011a, p. 409).

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Bem and his team also examined participants’ precognitive test performance in relation to a certain personality characteristic known as “stimulus-seeking.” This is related to the broader personality characteristic of extraversion, possessed by people who are highly sociable (i.e., if you are a highly outgoing person who enjoys being around people, you are likely to be characterized as an extravert). Because of their outgoing personality and desire to be active socially, extraverted people may be rather susceptible to boredom when alone or in socially dull situations, and may then want to seek out new and more stimulating situations. If that is so, then we might predict that extraverted people would also likely be high “stimulus-seeking” individuals. Previous research has produced statistical evidence to suggest that extraversion may be associated in some way with positive performance on ESP tests (Honorton et al., 1998). On the basis of its relation to extraversion, we might predict that people who rate themselves highly on a basic scale of stimulus-seeking would also perform well on the precognition test, given its stimulating nature with the use of erotic pictures. This is exactly what Bem and his team predicted in their experiment. The results from Bem’s Experiment 1 are graphically summarized in Figure 2 below. As indicated by the bar on the far left, the participants were able to produce an overall hit rate (53.1%) on the erotic trials that was significantly higher than the chance-expected rate of 50%, with odds against chance of around 100 to 1. In contrast, the hit rate on the control trials using non-erotic pictures (second left bar) was below the chance rate, and not statistically significant. As predicted, people who rated themselves as high in stimulus-seeking performed extremely well on the erotic trials, with an overall hit rate of 57.6%.

Precognitive Detection of Erotic Pictures (Bem Experiment 1)

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Erotic Non-Erotic (Control) High Stimulus Seekers Low Stimulus Seekers

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Figure 2. Summary of the results from Bem’s Experiment 1. Below each bar is an estimate of the statistical significance, in terms of odds against chance (usually in psychology, odds of at least 20 to 1 are taken to be statistically significant). The red horizontal line at 50% indicates the hit rate expected by chance.

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Experiment 2: Precognitive Avoidance of Negative Pictures To test the idea of avoiding negative things, Bem and his team opted to use affective pictures of negative content, like those used in the presentiment experiments described above. As in the first experiment, this second one was comprised of a two-choice precognition test, although a slightly different approach was taken. An illustration of the experiment is shown in Figure 3 below. During the experiment, the participant again sat before a computer screen. After the brief relaxation period, he or she completed 36 test trials. At the beginning of each trial, the computer displayed a neutral picture alongside a mirror image of that picture (Step 1 in Figure 3). The participant is then asked to choose the picture that he or she likes better (Step 2). After the participant has selected a picture, the computer randomly selects one of the two as the target (Step 3), which determines the kind of feedback picture that will be subliminally shown to the participant by flashing it rapidly on the screen, just on the edge of perception (Step 4). If the neutral picture preferred by the participant was the one selected as the target, then the computer flashes a positive (erotic) picture to the participant. However, if the neutral picture preferred by the participant was not the target, then the computer rapidly flashes a negative (threatening) picture to the participant. After a short pause, the process begins again at Step 1 for the next trial. The general idea here is that the participant is trying to hit the target (which leads to the positive picture) while avoiding the non-target (which leads to the negative picture). Since the computer selects the target only after the participant has made a choice, it is thought that the participant will have to use precognition in order to know which of the two neutral pictures the target will be.

Figure 3. A basic illustration of the experimental test for the precognitive avoidance of negative pictures (Bem’s Experiment 2). With two pictures for the participant to choose from, the probability of a hit is again 1 in 2 (50/50). And with the participant predicted to prefer the target while avoiding the non-target, the precognition hypothesis would again predict that the participant’s hit rate will be notably above the chance rate of 50%.

1. Participant is shown a

subliminal (rapid) flash: 33 milliseconds

if target: positive

if non-target: negative

2. Participant is asked to 3. Computer randomly 4. If target picture is the one neutral picture alongside choose the picture he or selects one picture as that participant chose, then a its mirror image she likes better the target positive (erotic) image is rapidly

shown. Otherwise, a negative (threatening) picture is shown

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The results summary for Bem’s Experiment 2 is shown in Figure 4 below. The far left bar indicates that, as predicted, the participants tended to prefer the future target picture, and had collectively produced a significant, above chance hit rate of 51.7%. Another way of saying this is that the participants had successfully avoided the non-target (associated with the negative picture) to a significant degree. Like in Experiment 1, participants who rated themselves as stimulus-seekers again performed well on the test.

Precognitive Avoidance of Negative Pictures (Bem Experiment 2)

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Figure 4. Summary of the results from Bem’s Experiment 2. Above each bar is an estimate of the statistical significance, in terms of odds against chance. The red horizontal line at 50% indicates the chance expected hit rate.

Retroactive Priming Experiments 3 and 4 in Bem’s (2011a) article were also initially reported at the 2008 PA Convention (Bem, 2008), and deal with a well-known psychological effect known as priming, which can have a subtle influence on a person’s judgment of the emotional affectiveness of a certain object. To explain what this means, it is probably best to illustrate it, as I have done in the top part of Figure 5 below. In a typical priming experiment in conventional psychology, a participant sits before a computer screen that initially displays a fixation point, which focuses the participant’s vision toward the center of the screen (the crosshairs in Step 1 at the top of Figure 5). A short time later, the participant is shown a picture and asked to judge, as quickly as they can, whether it shows something pleasant or unpleasant (Step 4). But right before the picture is shown, a word (called a prime, which can either be positive or negative) is subliminally shown to the participant by flashing it quickly on the screen, just on the edge of perception (Step 2). Experiments indicate that

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participants tend to respond faster in their judgments when the picture and the flashed prime are consistent in emotion (i.e., they are either both positive or both negative) than when they are inconsistent (i.e., one is positive, but the other is negative) (Klauer & Musch, 2003). The bottom part of Figure 5 illustrates Bem’s parapsychological version of the priming experiment, which is essentially the same as the typical experiment, except that it is (in a sense) run backwards. Instead of presenting the prime word before the participant’s judgment, the computer presents it after the judgment (Step 4 at the bottom of Figure 5). In this case, in order to influence the participant’s judgment in the past, it is thought that the priming effect will have to work backwards in time. Another way to look at it is that the participant has a precognitive impression of the prime that he or she will be shown in the future. In light of this scenario, Bem and his team labeled this parapsychological version of the experiment as retroactive priming (i.e., a backwards-acting priming effect).

Priming Effect (conventional psychology):

TYPICAL RESPONSE TIME:cute faster if prime was “cute” or

ugly than if prime was “ugly”

2. A prime word (positive1. A fixation point (cross) 3. Blank screen for 4. Picture is shown, and or negative) is quickly is shown on the screen 150 milliseconds participant is asked to flashed (150 msec.) quickly judge whether it

is positive or negative

Retroactive Priming (parapsychology):

TYPICAL RESPONSE TIME:faster if prime was “tasty” tastythan if prime was “bitter” or (but note here that response bitterwas made BEFORE prime

Figure 5. A basic illustration of a typical priming experiment in conventional psychology (top) and Bem’s parapsychological version of the experiment (bottom), as each would look on a computer screen. Carefully note that in Step 2 at the top and Step 4 on the bottom, two prime words are shown together on the screen for the sake of the example. In the actual experiment, only one of these words would appear on the screen. In Experiments 3 and 4, participants completed a series of 64 test trials. In half of the trials, the participants were faced with the retroactive version of the priming experiment. Then in the other half, the participants experienced the typical version. The results indicated that, in both cases, the participants’ judgments were influenced by the priming effect. In the typical version, the participants showed a significant tendency to respond 23 to 27 milliseconds faster when the picture and prime were consistent than when they were inconsistent, at odds greater than 100,000 to 1 against chance. In the retroactive version, the participants showed a tendency to respond 15 to 17 milliseconds faster, which, despite a being smaller difference, is still significant at odds

1. A fixation point (cross) is shown on the screen

2. Picture is shown, and participant is asked to quickly judge whether it is pleasant or unpleasant

3. Blank screen for 4. A prime word (positive is shown)

300 milliseconds or negative) is quickly flashed (500 msec.)

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between 42 (Exp. 4) and 166 (Exp. 3) to 1 against chance. This offers evidence to suggest that the priming effect may work backwards as well as forward. A slight variation of Bem’s priming experiment was used in a recent study conducted at the University of Edinburgh to explore the possible relation between mental health and paranormal experiences (Rabeyron & Watt, 2010). In this variation, the picture became the prime, and the participant made a judgment on whether the word was pleasant or unpleasant. Otherwise, the experiment was the same as Figure 5. Although the participants showed the typical priming effect in this variation, they did not clearly show a retroactive priming effect. The latter finding might have been due to the slight change made in the experiment, or to the subtle nature of the effect (i.e., it’s so subtle that it is not expected to reliably occur each and every time). Further attempts to repeat Bem’s priming experiment, whether directly or conceptually (as in the variation), are needed to learn more.

Retroactive Habituation Experiments 5 and 6 in Bem’s (2011a) article were initially reported at the 2003 PA Convention (Bem, 2003), and are based on a well-known psychological effect called habituation. This in turn is based on a well-known psychological effect known as the Mere Exposure Effect, in which people come to like a certain object or sensation after they have been exposed to it a number of times (i.e., the more they are exposed to it, the more they come to like it). A simple example of this effect might be gradually coming to like a certain catchy tune after you’ve heard it a few times on the radio. The effect may also be akin to the idea that “we like what we are used to.” The illustration in the top part of Figure 6 shows how the effect is typically induced in conventional psychological experiments. In the typical experiment, a participant sits before a computer screen that is initially blank. After a short time, a negative picture is subliminally shown to the participant by flashing it several times on the screen in rapid succession, just on the edge of perception (Step 1 in the top part of Figure 6). In most cases, this subliminal exposure occurs so fast that the participant is able to realize that the picture has just been shown, but is not able to recognize exactly what it showed. Following this subliminal exposure, the participant is shown two negative pictures side-by-side on the screen (Step 2) and asked to choose the one he or she prefers more (Step 3). Even though the participant is not likely to have recognized the content of the subliminally flashed picture, he or she still tends to select that picture as the preferred one. The reasoning behind this might seem a bit unclear or confusing to some readers, so let me try to explain: By exposing it to the participant several times beforehand (despite how fast that exposure was), the subliminally flashed picture loses some of its negative emotional intensity. In a sense, by being exposed to it, the participant becomes somewhat “used to” the picture (hence the term “habituation”) and prefers it because of its reduced negative emotional impact on him or her (as compared to the emotional impact of the other picture, which the participant hasn’t been exposed to before). An analogy might be drawn to a more familiar situation: let’s say that we’re watching a scary movie on DVD, and a monster suddenly jumps in front of the screen to frighten us, when we’re not expecting it. Our usual instinctive response is to jump up and yell in fright. But then if we rewind the DVD and see the same monster scene again, we are not as scared because we’ve already seen it before and are expecting it. In other words, we have already become used to seeing it. And in principle, the more we watch it again, the less scared we will become. That is the purpose that the subliminally flashed picture is meant to serve: it effectively lessens

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our emotional arousal (fear or disgust) to the negative image as we become used to seeing it several times, even briefly (hence the term “mere exposure”). By becoming “used to” (i.e., habituated) the picture in this manner, its emotional impact on us becomes less effective and thus, we might prefer it over other negative pictures that we’ve never seen before. Another experiment has demonstrated that negative words can be just as effective as pictures in producing the Mere Exposure Effect when subliminally flashed to the participant (Dijksterhuis & Smith, 2002). As it might now seem clear, the Mere Exposure Effect has been known about for some time, but it was the research of social psychologist Robert Zajonc (1968, 2001) that really led to its close empirical study. Between 1968 and 1987, a total of 208 experiments on the effect had been published, and a meta-analysis of these by psychologist Robert Bornstein (1989) provided highly significant evidence for its effectiveness, with odds of well over 10 million to 1 against chance. At one point, the sales media had reportedly tried to take advantage of this effect to sell products by quickly flashing subliminal messages such as “Drink Coke” on TV and movie screens, in the hope that doing this would subtly influence peoples’ preferences toward the product and persuade them to buy it (Merikle, 2000). The bottom part of Figure 6 shows Bem’s parapsychological version of the experiment on the Mere Exposure Effect. It is essentially the same as the typical version of the experiment, with the exception that it is (in a sense) run backwards. Instead of subliminally flashing the negative picture before the participant makes a preferred picture choice, it is only flashed after the participant’s choice (Step 4 at the bottom of Figure 6). It is thought that, in order to habituate the participant to the subliminally flashed picture in the past, the effect will have to, in a sense, work backwards in time. Another way to look at it is that the participant has a precognitive impression of the picture that he or she will be subliminally shown in the future. In light of this scenario, Bem and his team labeled this parapsychological version of the experiment as retroactive habituation (i.e., a backwards-acting habituation effect).

(Figure 6 can be found on the next page)

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Habituation by the Mere Exposure Effect (conventional psychology): subliminal (rapid) flash: 17 milliseconds

2. Participant is shown 1. Computer flashes one negative 3. Participant is asked to two pictures side-by-side, picture to the participant in rapid choose the one that he orwhich are roughly matchedsuccession, barely on the edge of she prefers more in their negativity perception

Retroactive Habituation (parapsychology):subliminal (rapid) flash: 17 milliseconds

1. Participant is shown 2. Participant is asked to 3. Computer randomly 4. Computer flashes the target to two pictures side-by-side, choose the one that he or selects one picture to be the participant in rapid succession,which are roughly matched she prefers more the target barely on the edge of perception in their negativity

Figure 6. A basic illustration of a typical experiment on habituation in conventional psychology (top) and Bem’s parapsychological version of the experiment (bottom). Experiment 5: Retroactive Habituation I In Experiment 5, participants completed 48 trials in the retroactive habituation test as shown at the bottom of Figure 6. Because the participant again has two pictures to choose from, the probability of getting a hit is 1 in 2 (50/50). Since it is thought that the participant will prefer the target picture that the computer will subliminally flash in the future, the precognition hypothesis predicts that the participant will be able to score a hit rate significantly above the 50% expected by chance. The results of the experiment are summarized on the left side of Figure 7 below. As predicted, the participants collected obtained a hit rate of 53.1%, significantly above chance at odds of 70 to 1. In contrast, control test trials in which neutral pictures were used instead of negative ones resulted in a hit rate of 49.4%, which is slightly below chance and not statistically significant.

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Retroactive Habituation (Bem Experiments 5 & 6)

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Figure 7. Summaries of the results from Bem’s Experiments 5 and 6. Above or below each bar is an estimate of the statistical significance, in terms of odds against chance. The red horizontal line at 50% indicates the chance expected hit rate. Note that the hit rate was predicted to be above chance for negative pictures, and below chance for erotic pictures (see text for explanation). Experiment 6: Retroactive Habituation II (Erotic Pictures) The Mere Exposure Effect appears to produce the opposite effect for positive (erotic) pictures. Needless to say, erotic pictures can often produce a lot of excitement and sexual arousal in us. However, if we are repeatedly exposed to the same erotic image, the excitement and arousal that it produces can become less effective on us because we may become “bored” of it (i.e., habituated to it). In the typical habituation experiment, exposure to a subliminally flashed positive picture is thought to produce this same kind of “boredom” effect. Thus, when erotic pictures are used in the experiment instead of negative ones, it is predicted that when the participant is shown two erotic pictures side-by-side (as in Step 2 at the top of Figure 6) and asked to choose the one he or she prefers (Step 3), the participant will not choose the picture that was subliminally flashed beforehand in Step 1. In other words, the participant will prefer the non-target picture. Extending this to the retroactive habituation experiment (bottom of Figure 6), it is predicted that the participant will not choose the picture that will be subliminally flashed to them in the future. How will they know which one that will be? This is where precognition is assumed to play its role. On this basis, it is predicted that the participant will actually avoid (or miss) the target rather than hit it, since the target picture is the one that will be subliminally flashed. Thus, the participants should show a hit rate that is below chance rather than above it. This is the prediction that was tested in Experiment 6, and as we can see from the middle bar on the right side of Figure

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7, that prediction was confirmed: the participants scored a hit rate of 48.2% when the erotic pictures were used, which is significantly below the 50% expected by chance. In addition, Bem and his team again tested participants with negative pictures to see if the result from Experiment 5 (first bar on the left side of Figure 7) could be reproduced. Indeed, the participants again scored significantly above chance (51.8%, first bar on the right side of Figure 7). In contrast, control test trials using neutral pictures again resulted in a hit rate that was slightly below chance and not significant (last bar on right side of Figure 7). However, something unexpected and of potential interest arose in the trials using the neutral pictures when they were looked at a bit more closely, and that became the focus of Experiment 7 (discussed below). Other Retroactive Habituation Experiments by Independent Researchers Already there have been a few independent researchers who have performed experiments to try and reproduce Bem’s findings on retroactive habituation. One experiment (Hadlaczky, 2006), conducted at the University of Stockholm, was an effort to reproduce Bem’s quite closely (by using the same computer software), with one of the only differences being that it had used a slightly higher number of subliminal flashes than in Bem’s experiments. However, the resulting hit rate was at chance, which could be due to the noted difference or perhaps even to the subtle nature of the effect. Another experiment (Batthyány, 2010), conducted at the University of Vienna, attempted to reproduce Bem’s findings by testing female participants in groups of five. The procedure was roughly the same as in Bem’s experiment (bottom of Figure 6), except that in this variation, each pair of images was projected onto a wall for ten seconds, during which time each participant in the group wrote down her preferred picture in a booklet. When this ten-second period was up, the computer randomly selected the target and subliminally flashed it (as in Steps 3 & 4 at the bottom of Figure 6) to the group. Comparable to Bem’s participants, the group participants in this study produced a significant, above-chance hit rate of 53.3%, which has odds of about 50 to 1 against chance. Efforts by two other research groups have produced some intriguing results. A team from Liverpool Hope University College in the UK performed a slight variation of Bem’s experiment, in which the participants were people who were afraid of spiders (Savva et al., 2004). Instead of being shown negative pictures (as in Step 1 at the bottom of Figure 6), the spider-fearing participants were shown two matched pictures of spiders (which could be considered negative pictures to the participants because of their admitted arachnophobia). After the participants chose their preferred picture, the computer randomly selected one of the spider pictures and subliminally flashed it (as in Steps 3 & 4). Following the same prediction for negative pictures, it was predicted that the participants would prefer the spider picture that would be flashed to them in the future. This is what was indeed found for the spider-fearing participants, while other participants who were not afraid of spiders showed no such preference. The Liverpool Hope team attempted to reproduce this finding in a follow-up study consisting of two experiments (Savva et al., 2005). In the first experiment, the spider pictures were supraliminally flashed (meaning that they were flashed long enough for the participant to recognize the content of the picture) rather than subliminally flashed. Although the participants in this first experiment had produced an overall hit rate (53%) that was above chance and significant, the difference between the spider-fearing participants and the other (non-fearing) participants was not reproduced. Post-test interviews with the participants had revealed some of them had shut

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their eyes or turned their heads when the spider picture was flashed, which could explain why the difference was not reproduced. To control for this, the Liverpool Hope team monitored the participants in their second experiment and reminded them not to cover their eyes or turn away when the spider picture was flashed. Despite this, the overall hit rate was at chance in the second experiment, and the difference was again not reproduced. However, the Liverpool Hope team did find something of possible interest when they examined the data after the fact, which relates to the effects described in Bem’s Experiment 7 (described in the next section below). In another experiment conducted at the University of Gothenburg in Sweden (Parker & Sjödén, 2010), participants experienced the Mere Exposure Effect both in its typical form (top of Figure 6) and in its parapsychological form (retroactive habituation; bottom of Figure 6). The results suggested that participants who showed habituation by the Mere Exposure Effect had also shown retroactive habituation. In other words, participants who exhibited habituation in its typical form could also apparently exhibit its precognitive form. These two experiments seem to offer some preliminary promise for potentially verifying and extending Bem’s findings, although other experiments must still be done.

Retroactive Induction of Boredom (and Aversion) As mentioned, something unexpected and of potential interest arose in the retroactive habituation test trials that used neutral pictures. We saw that, initially, the neutral pictures tended to produce hit rates that were close to chance and not statistically significant (Figure 7). However, Bem and his team noticed in Experiment 6 that when the neutral picture selected as the target was subliminally flashed to the participants at least ten times, the participants started avoiding (or missing) it to a statistically significant degree (i.e., they produced a hit rate that was significantly below chance, as indicated by the far left bar in Figure 8 below). Of this, Bem (2011a) notes: “As with a too frequent TV commercial, the many repeated exposures [i.e., subliminal flashes] retroactively rendered the neutral target picture boring, or even aversive, and hence less attractive than its matched non-target” (p. 417). Bem initially reported this result at the 2005 PA Convention (Bem, 2005), and the attempt to reproduce it became the focus of Experiment 7. As shown in Figure 8 below, the results of Experiment 7 indicated that the participants produced a hit rate that was below chance. Although it was in the right direction, the hit rate is not statistically significant. However, it was mentioned previously that people who rate themselves high on the stimulus-seeking scale may be rather susceptible to boredom. If that is so, then one might predict that participants who rate themselves high on stimulus-seeking should also produce a significantly below chance hit rate. That is what Bem and his team found, as indicated by the third bar in Figure 8. As a result, they labeled this effect as the retroactive induction of boredom (i.e., a backwards-acting “boredom” effect).

(Figure 8 can be found on the next page)

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Retroactive Induction of Boredom (Bem Experiment 7)

46

47

48

49

50

51

Experiment 6 Experiment 7 High Stimulus Seekers Low Stimulus Seekers

Hit

Rat

e (%

)

24 to 1 odds

9 to 1 odds

52 to 1 odds

< 2 to 1 odds

Figure 8. Summaries of the results from the retroactive habituation test trials in Bem’s Experiments 6 and 7 that used neutral pictures subliminally flashed ten times. Above or below each bar is an estimate of the statistical significance, in terms of odds against chance. The red horizontal line at 50% indicates the chance expected hit rate. Note that the hit rate was predicted to be below chance for the neutral pictures in this case (see text for explanation). Retroactive Aversion It was mentioned in the previous section that the team at Liverpool Hope University College had possibly found something interesting after the fact in the second experiment of their follow-up study on retroactive habituation using spider pictures (Savva et al., 2005). This finding relates to retroactive aversion, an effect similar to the retroactive induction of boredom. As Bem (2011a, p. 417) notes in the quote cited above, repeated exposure to the subliminally flashed picture can sometimes make the picture become aversive. (An analogy can be drawn to the example Bem gives of the too frequent TV commercial: when you’ve seen the same commercial on TV one too many times, not only do you get bored of it, you also begin to get “sick and tired” of seeing it.) And if the picture becomes aversive, then the participants who find it aversive (such as the participants who are not afraid of spiders, because the spider pictures have no effect on them) may start to avoid it, rather than hit it. Like in the retroactive induction of boredom, we should see these participants produce a hit rate that is significantly below chance in such a case. And that is what the Liverpool Hope team found when they reexamined the data from their second experiment. Instead of the chance-expected hit rate of 50%, the participants who were not afraid of spiders had obtained a 45% hit rate, which has odds of about 62 to 1 against chance.

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Since this finding was obtained after the fact, it should be taken with caution, but it seems to call for further empirical exploration of retroactive aversion.

Retroactive Facilitation of Recall We may often take it for granted that we are able to remember things that have happened to us in the past, but what if we could remember things that happen in the future? Such an idea was alluded to by Louisa Rhine (1954), the matriarch of modern parapsychology, in her study of spontaneous precognitive experiences in everyday life. She noticed that in their accounts, many of the people who experienced precognition “… have marvelled [sic] at the fact that the experience was just like ‘remembering’ the future” (p. 121). Bem (2011a) alludes to a similar idea in an excerpted scene he cites from Lewis Carroll’s classic tale Alice in Wonderland. Bem notes that in this scene, “… the White Queen explains to Alice that the citizens of her country have precognitive ability; or, as she puts it, ‘memory works both ways in her land’ and she herself remembers best ‘things that happened the week after next.’ When Alice says that ‘I’m sure mine only works one way … I can’t remember things before they happen,’ the Queen disparagingly remarks, ‘It’s a poor sort of memory that only works backwards’” (p. 419). Although it would clearly go against our common everyday view about how memory works, possessing the ability to remember the future would certainly seem to be advantageous. As social psychologist Melissa Burkley (2010) points out, “How much better would our lives be if we could live in the White Queen’s kingdom, where our memory would work backwards and forwards? For instance, in such a world, you could take an exam and study for it afterwards to make sure you performed well in the past.” Bem and his team essentially designed Experiments 8 and 9 with Burkley’s exam suggestion in mind to explore the possibility that memory can work backwards as well as forward. Figure 9 illustrates the experiment, which generally proceeded as follows: A participant sits before a computer screen, which displays a long list of 48 words taken from four separate categories (foods, animals, clothes, and occupations). Each word in the list is shown one at a time, and the participant is asked to visualize each one (Step 1). Then, after all of the words in the list have been shown, the participant is suddenly given a “pop quiz,” in which he or she is asked to type down as many words as he or she can recall from the list (Step 2). Afterward, the computer randomly selects half of the words from the list (i.e., 24 words; 6 from each of the four categories) to serve as practice words (Step 3). The remaining words, which were not selected by the computer, serve as non-practice (control) words. The computer then presents the selected practice words in a new randomized list on the screen, and the participant is asked to “study” them by locating in the list the six words that belong each category, selecting them, and then re-typing them (Step 4). Based on the idea that the practice effects of this post-quiz “study” session may work backwards in time, the precognition hypothesis predicts that the participant will recall more of the practice words during the pop quiz than the non-practice (control) words to a significant degree.

(Figure 9 can be found on the next page)

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Figure 9. A basic illustration of the experiment on the retroactive facilitation of recall (Bem’s Experiments 8 and 9). The precognition hypothesis basically assumes that the practice effects of Step 4 may (in a sense) work backwards in time to affect the participant’s quiz performance in Step 2. Carefully note that in Step 1, the list of words is shown on the screen for the sake of the example. In the actual experiment, each of the words would only be shown one at time on the screen, without any of the others present. Also, in Step 4, the words in the practice list would be found, selected, and re-typed into their categories (in this example, they’re not; the two selected words are not in the same category, and are highlighted here simply to be consistent with Steps 2 & 3). On the surface, the results of the two experiments seemed to offer statistical evidence to support the idea that practicing a list of words in the future can affect quiz performance in the past, with odds of 33 to 1 against chance in Experiment 8. During the study session in Experiment 9, the participants were instead presented with the practice words (set into their proper categories) and simply asked to visualize them again as in Step 1. In this case, they did even better on the quiz, with odds against chance of 500 to 1 against chance. There is, however, a potential caveat. In examining these results, University of Hertfordshire psychologist Richard Wiseman (2010) noticed the possibility that, when the researchers were scoring the quizzes and correcting any misspelled words, they may have already known which words were practice words, and which words were not. If that is so, then Wiseman suggests that “[t]his procedure presented an opportunity for subjective bias to enter the scoring system” where, in the process of correction, the researchers could (consciously or unconsciously) alter the words to produce spurious correct answers (i.e., false hits). Bem (in Wiseman, 2010) has provided a response to this criticism, noting that the computer system is designed in such a way that any corrections are logged and can be compared against a copy of the original data. Moreover, an original copy of the data record is retained that cannot be altered. In addition, Bem showed that misspelled words do not significantly change any of his positive results. Despite this, additional studies will need to be carried out in order to better control for this issue. At least one additional study has been already been carried out by two psychologists who attempted to reproduce Bem’s findings on the retroactive facilitation of recall. Their study (Galak & Nelson, 2010) was essentially the same as Bem’s, with the exception that it was conducted entirely on-line (over the Internet). They were unable to reproduce his findings. An issue might be raised, however, with the fact that theirs was an on-line study, in that there are many uncertainties about the factors that may have an effect on performance. For instance, it is not clear whether the participants had completed the experiment in a place where they were entirely free of distractions.

1. Participant is shown a list of 48 words, one at a time, and asked to visualize them (e.g., toast)

2. Participant is next given a “pop quiz,” in which he/she isasked to type as many wordsfrom the list as he/she can recall

3. Computer randomly selects 24 words from the list (6 from each of the four categories in list)to be practice words

4. Computer presents practice words in a randomized list, and participant is asked to find,select, and re-type them

salad teacher scarf cat doctor toast horse shoes

cat bread toast...horse... toast socks jeans...? janitor frog

apple jeans

jeans…toast… type

type

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Performing the experiment in a laboratory helps to better control for such varying factors. This issue seems to be especially critical when it comes to a controversial topic such as psychic phenomena. For now, we’ll just have to wait and see what results come out of additional experiments.

Conclusion Bem’s latest series of experiments on precognition certainly provide some interesting and promising results; as Bem (2011b) himself notes: “Across all nine experiments, the combined odds against the findings being due to chance are greater than 70 billion to 1.” But as always in parapsychology, there is still much additional work to be done. If the few attempts made so far are anything to go by, efforts to repeat a parapsychological experiment and obtain similar findings can sometimes be rather complicated and difficult. Such tends to be the nature of mental phenomena that are inherently subtle, vary greatly from person to person, and which depend primarily upon statistical evaluation, so a number of experiments are usually needed before any firm conclusions can be drawn (and this goes not just for psychic phenomena, but also for many other forms of human behavior). But apart from their positive results, one big advantage to Bem’s experiments is that they introduce experimental methods for testing precognition (and psychic phenomena in general) that are simple in design and relatively easy to perform. In particular, Bem notes that these experiments make use of familiar psychological effects, take only 15 to 30 minutes to complete, and require little equipment other than a computer. Hopefully, this should encourage other researchers, both in and out of parapsychology, to adopt Bem’s methods and perform additional experiments to try and further confirm his results. And if researchers inside and outside of parapsychology are able to reproduce them to at least a fair degree, then perhaps mainstream psychology will begin to treat the topic of psychic phenomena a bit more seriously. We have yet to see what the future may bring, so to speak, but there now seems to be a promising avenue for testing precognition as it might occur under more “real world” circumstances. With this promise leading the way, let’s just see what the future brings, shall we?

Notes 1) The other types of precognitive cases include dreams, which seem to be the most common type at 57%; and vivid sensory-like hallucinations, which make up only about 13% (Feather & Schmicker, 2005, p. 37; Rhine, 1954). 2) For those readers who are familiar with the research literature of parapsychology, you might recall that it was Professor Bem who co-authored, along with the late Charles Honorton of Psychophysical Research Laboratories (PRL) in New Jersey, the well-known article describing the meta-analysis of the successful series of automated ganzfeld ESP studies conducted at PRL, which was published in the prominent mainstream journal Psychological Bulletin in 1994 (Bem & Honorton, 1994). 3) Of course, we all have the ability to anticipate (or “predict”) the occurrence of some future events through logical inference, so at first, this finding may not seem like much. However, the key thing to keep in mind when it comes to presentiment is that the future event (seeing the affective picture) occurs at random times. And if it occurs randomly, then it is not possible to predict its occurrence through inference because you don’t know exactly when it will occur, since it doesn’t follow a set pattern. And if we don’t know when it will occur, how can we possibly respond to it beforehand? This is where precognition (in the form of the presentiment response) is thought to play its role. 4) For readable summaries of the presentiment experiments, see the relevant chapters in the books by Radin (1997a, Ch. 7; 2006a, Ch. 10). He also reviews these and similar types of experiments in an article appearing in a separate conference anthology (Radin, 2006b).

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5) In addition to the basic summary I provide here, there are several blog articles available on the Internet that provide short summaries of Bem’s experiments, and that are accessible to the general reader. Some of these, such as the one on Oklahoma State University psychologist Melissa Burkley’s (2010) “The Social Thinker” blog on the Psychology Today website, are positive and open-minded. Others, such as that written by York University psychologist James Alcock (2010), are critical and represent the typical skeptical viewpoint toward precognition and psychic phenomena in general. As noted by Dean Radin (2010), a close look at some of these blogs (such as Alcock’s) often reveals standard skeptical arguments that are not always well supported by the parapsychological research literature. See also Bem’s (2011b) response to Alcock’s blog. The World of Parapsychology website has compiled a running list of on-line commentaries and critiques relating to Bem’s experiments, which can be found at this URL: http://www.thewop.org/?s=daryl+bem. 6) These tests include the early card-guessing tests, as well as computerized tests in which people were asked to predict the target that would later be selected by an electronic random number generator. Incidentally, a meta-analysis of these tests by the late Charles Honorton and Diane Ferrari (1989) indicated that they collectively showed positive statistical results for precognition, which were associated with astronomically high odds against chance (well over a billion to one). Thus, there was already a sound empirical basis for Bem’s chosen approach.

References Alcock, J. (2010, December 3). Back from the future: Comments on Bem. Committee for Skeptical Inquiry

blog article available at: http://www.csicop.org/specialarticles/show/back_from_the_future. Downloaded December 7, 2010. (Also appears an article in the March/April 2011 issue of The Skeptical Inquirer)

Batthyány, A. (2010, November). Retrocausal habituation and induction of boredom: A successful replication of Bem (2010; Studies 5 and 7). Preprint article available over the Internet at: http://ssrn.com/abstract=1715954. Downloaded February 10, 2011.

Bechara, A., Damasio, H., Tranel, D., & Damasio, A. R. (1997). Deciding advantageously before knowing the advantageous strategy. Science, 275, 1293 – 1295.

Bem, D. J. (2003). Precognitive habituation: Replicable evidence for a process of anomalous cognition. Proceedings of Presented Papers: The Parapsychological Association 46th Annual Convention (pp. 6 – 20). Cary, NC: Parapsychological Association, Inc.

Bem, D. J. (2005). Precognitive aversion. Proceedings of Presented Papers: The Parapsychological Association 48th Annual Convention (pp. 31 – 35). Petaluma, CA: Parapsychological Association, Inc.

Bem, D. J. (2008). Feeling the future III: Additional experimental evidence for apparent retroactive influences on cognition and affect. Proceedings of Presented Papers: The Parapsychological Association 51st Annual Convention (pp. 24 – 32). Columbus, OH: Parapsychological Association, Inc.

Bem, D. J. (2011a). Feeling the future: Experimental evidence for anomalous retroactive influences on cognition and affect. Journal of Personality and Social Psychology, 100, 407 – 425.

Bem, D. J. (2011b, January 6). Response to Alcock’s “Back from the Future: Comments on Bem.” Committee for Skeptical Inquiry blog response article available at: http://www.csicop.org/specialarticles/show/response_to_alcocks_back_from_the_future_comments_on_bem. Downloaded January 13, 2011.

Bem, D. J., & Honorton, C. (1994). Does psi exist? Replicable evidence for an anomalous process of information transfer. Psychological Bulletin, 115, 4 – 18.

Bierman, D. J. (2000). Anomalous baseline effects in mainstream emotion research using psychophysiological variables. Proceedings of Presented Papers: The Parapsychological Association 43rd Annual Convention (pp. 34 – 47). Raleigh, NC: Parapsychological Association, Inc.

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Bierman, D. J., & Radin, D. I. (1997). Anomalous anticipatory response on randomized future conditions. Perceptual and Motor Skills, 84, 689 – 690.

Bierman, D. J., & Radin, D. (1999). Conscious and anomalous nonconscious emotional responses: A reversal of the arrow of time? In S. R. Hameroff, A. W. Kazniak, & D. J. Chalmers (Eds.) Towards a Science of Consciousness III: The Third TUSCON Discussions and Debates (pp. 367 – 385). Cambridge, MA: Bradford/MIT Press.

Bornstein, R. F. (1989). Exposure and affect: Overview and meta-analysis of research, 1968 – 1987. Psychological Bulletin, 106, 265 – 289.

Broughton, R. S. (2006). Encounters at the frontiers of time: Questions raised by anomalous human experiences. In D. P. Sheehan (Ed.) Frontiers of Time, Retrocausation – Experiment and Theory (pp. 329 – 339). AIP Conference Proceedings Vol. 863. Melville, NY: American Institute of Physics, Inc.

Burkley, M. (2010, October 11). Have scientists finally discovered evidence for psychic phenomena? New studies show people can anticipate future events. Psychology Today “The Social Thinker” blog article available at: http://www.psychologytoday.com/blog/the-social-thinker/201010/have-scientists-finally-discovered-evidence-psychic-phenomena. Downloaded December 3, 2010.

Dijksterhuis, A., & Smith, P. K. (2002). Affective habituation: Subliminal exposure to extreme stimuli decreases their extremity. Emotion, 2, 203 – 214.

Dossey, L. (2009). The Power of Premonitions: How Knowing the Future Can Shape Our Lives. New York: Dutton Adult.

Feather, S. R., & Schmicker, M. (2005). The Gift: ESP, the Extraordinary Experiences of Ordinary People. New York: St. Martin’s Press.

Galak, J., & Nelson, L. D. (2010, October 29). A replication of the procedures from Bem (2010, Study 8) and a failure to replicate the same results. Preprint article available over the Internet at: http://ssrn.com/abstract=1699970. Downloaded December 3, 2010.

Globisch, J., Hamm, A. O., Esteves, F., & Öhman, A. (1999). Fear appears fast: Temporal course of startle reflex potentiation in animal fearful subjects. Psychophysiology, 36, 66 – 75.

Hadlaczky, G. (2006). Precognitive habituation: An attempt to replicate previous results. Preprint article available over the Internet at: http://www.essays.se/essay/fe6b43b515/. Downloaded December 3, 2010.

Honorton, C., & Ferrari, D. C. (1989). “Future telling”: A meta-analysis of forced-choice precognition experiments, 1935 – 1987. Journal of Parapsychology, 53, 281 – 308.

Honorton, C., Ferrari, D. C., & Bem, D. J. (1998). Extraversion and ESP performance: A meta-analysis and a new confirmation. Journal of Parapsychology, 62, 255 – 276.

Klauer, K. C., & Musch, J. (2003). Affective priming: Findings and theories. In J. Musch & K. C. Klauer (Eds.) The Psychology of Evaluation: Affective Processes in Cognition and Emotion (pp. 7 – 49). Mahwah, NJ: Lawrence Erlbaum Associates.

May, E. C., Paulinyi, T., & Vassy, Z. (2005). Anomalous anticipatory skin conductance response to acoustic stimuli: Experimental results and speculation about a mechanism. Journal of Alternative and Complementary Medicine, 11, 695 – 702.

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Radin, D. I. (1997a). The Conscious Universe: The Scientific Truth of Psychic Phenomena. San Francisco: HarperEdge.

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Radin, D. I. (2004). Electrodermal presentiments of future emotions. Journal of Scientific Exploration, 18, 253 – 273.

Radin, D. I. (2006a). Entangled Minds: Extrasensory Experiences in a Quantum Reality. New York: Paraview Pocket Books.

Radin, D. I. (2006b). Psychophysiological evidence of possible retrocausal effects in humans. In D. P. Sheehan (Ed.) Frontiers of Time, Retrocausation – Experiment and Theory (pp. 193 – 213). AIP Conference Proceedings Vol. 863. Melville, NY: American Institute of Physics, Inc.

Radin, D. I. (2010, December 3). My comments on Alcock’s comments on Bem’s precognition article. Entangled Minds blog article available at: http://deanradin.blogspot.com/2010/12/my-comments-on-alcocks-comments-on-bems.html. Downloaded December 7, 2010.

Rhine, L. E. (1954). Frequency of types of experience in spontaneous precognition. Journal of Parapsychology, 18, 93 – 123.

Savva, L., Child, R., & Smith, M. D. (2004). The precognitive habituation effect: An adaptation using spider stimuli. Proceedings of Presented Papers: The Parapsychological Association 47th Annual Convention (pp. 223 – 229). Cary, NC: Parapsychological Association, Inc.

Savva, L., Roe, C. A., & Smith, M. D. (2005). Further testing of the precognitive habituation effect using spider stimuli. Proceedings of Presented Papers: The Parapsychological Association 48th Annual Convention (pp. 163 – 170). Petaluma, CA: Parapsychological Association, Inc.

Spottiswoode, S. J. P., & May, E. C. (2003). Skin conductance prestimulus response: Analyses, artifacts, and a pilot study. Journal of Scientific Exploration, 17, 617 – 641.

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