Terence Hines - Pseudoscience and the Paranormal

The convincing nature of prophetic dreams is enhanced by the fact that we don’t remember the vast majority of our dreams. In fact, some people never remember any dreams. But they do dream. When these individuals are brought into a sleep laboratory and awakened during a REM period, they report normal dreams. The dreams that are most likely to be remembered are ones that take place just before awakening in the morning or, more to the point of the present discussion, those that “come true.” If a dream doesn’t “come true” there is very little chance that it will be remembered. We have all had the experience of awakening and not remembering any dreams. Then, sometime later during the day, something happens to us, or we see or hear something that retrieves from our long-term memory a dream we had had, but which, until we were exposed to what is called a retrieval cue, we were unable to recall voluntarily. Of course, if we had not been exposed to the retrieval cue, we would never have been aware that the dream had occurred. Thus, the nature of memory for dreams introduces a strong bias that makes dreams appear to be much more reliably prophetic than they are—we selectively remember those dreams that “come true.”

Another familiar factor works to make dreams appear more prophetic than they are—the multiple out. People will frequently count a dream as “coming true,” even if the events in the dream and the events in real life are only somewhat similar. A personal example: One night when I was living in Boston, I had a dream about a horrible accident on the Boston subway system’s Green Line. In my dream the accident took place underground (a large part of the Green Line is above ground). There were many dead, much blood, and a great number of injured. I mentioned the dream to a friend. A few months later, there was an accident on the Green Line. A car empty of passengers was traveling on the section of track above ground. It derailed and rolled down a small embankment. No one was hurt and, since it was a Saturday, no one was really very much inconvenienced. Yet my friend was convinced that my dream had been a psychic prophecy that had come true. She was a bit miffed that I didn’t immediately agree that psychic phenomena were real.

Of course, the accident in my dream and the real-life accident were entirely different. To count the two as a “match” and classify my dream as prophetic would mean my dream almost had to come true: Sooner or later, some type of accident, large or small, will occur on any subway line. Further, dreams don’t come with little disclaimers at the end stating “this dream invalid for purposes of prophecy in thirty days.” Thus, they have practically an endless amount of time to come true. Given this, it’s hardly surprising that some do.

Alcock (1981) reports an experiment that shows that eliminating the opportunity for multiple outs in dreams eliminates their seemingly prophetic nature. He is often confronted by people who report that their dreams “always come true.” I have had people make similar reports to me. Alcock simply asks these people to keep a dream diary, in which they write down their dreams upon awakening. When this is done, the dreams all at once stop being accurate. The diary is a written record of the dream and it prevents the dreams from being “misremembered” as more accurate than they really were.

Hunches, intuition, and “feelings” that something is going to happen seem to be accurate more often than would be expected by chance, for similar reasons. We forget the hunches that don’t come true, but remember the ones that do. I used to own a secondhand Pinto. I often had hunches that something would go wrong with the car. Not surprisingly, eventually one of the hunches came true. Consider how multiple outs can operate to inflate the “hit rate” of hunches. A wife has a strong feeling that her husband has been involved in a serious car accident and becomes very worried. Upon returning from work, she finds her husband in perfect health. Was the hunch wrong? A believer in the prophetic power of hunches would be very likely to count the hunch as a hit if: (1) the husband had been in a minor accident; (2) had seen a serious accident ; (3) had seen a fender bender or minor accident; or (4) had seen what was almost a serious accident. After all, the believer in the prophetic nature of hunches or dreams will tell you, these things aren’t precise—they must be interpreted to make them meaningful. The interpretation always place takes place after the fact.

Seemingly amazing coincidences that have convinced some people of the reality of ESP are due to similar memory-biasing mechanisms. A classic example is to be thinking of someone and, minutes later, having them call. Is this sort of instance amazing proof of direct mind-to-mind communication? No—it’s just a coincidence. It seems amazing because we normally don’t think about the millions of telephone calls made each day and we don’t remember the thousands of times we have thought of someone when they haven’t called.

Hintzman, Asher, and Stern (1978) have nicely demonstrated selective memory for coincidences in a laboratory setting where the coincidences were under strict control. In one experiment, subjects rated a list of nouns on various characteristics (size and attractiveness). They were not told that they would later be asked to recall the words. After a brief “filler task” designed to pass the time and occupy the subjects’ attention, a set of pictures of objects was rated. Some of the pictures corresponded to some of the words that had been rated in the first part of the experiment and this correspondence was what was defined as a coincidence for the purposes of the experiment. When the subjects, without previous warning, had to recall as many of the words they had previously rated as they could, their memory was much better for words if that word’s corresponding picture had been rated in the picture-rating portion of the study. This occurred even if the subject didn’t notice that some of the pictures corresponded with the words.

In a second experiment Hintzman, Asher, and Stern (1978) showed that the same effect was found if the pictures were rated first. Finally, in a third experiment, it was found that the effect of the coincidence was maintained over a period of twenty-four hours. In this final study, a set of words was rated, then came a filler task, then a set of pictures was rated. Memory was not tested—again unexpectedly—until the next day. This series of experiments demonstrates that coincidences are better remembered than noncoincidences.

Related to hunches is the phenomenon of déjà vu, which means “already seen” in French. In a déjà vu experience, a place or situation seems familiar even though the person having the experience knows that he has never been in that place or situation before. Such experiences have led some people to conclude that they had visited the familiar location in a past life. One need not resort to reincarnation for an understanding of déjà vu; it can be understood in terms of normal memory function. Specifically, déjà vu results when two different memory processes that normally occur together occur separately. Usually when we find ourselves in a familiar location, we have both a memory of the previous experience or experiences at that location and a feeling of familiarity. In the déjà vu situation, the feeling of familiarity is present, but the memory of previous experience is not, either because it is too weak or because there was no previous experience. In this latter situation, the mechanism that generates the feeling of familiarity has briefly malfunctioned.

There is much laboratory evidence for the dissociability of actual retrieval of a memory and a feeling of familiarity (Gardiner and Richardson-Klavehn 2000). In the “tip of the tongue” situation (Brown and McNeill 1966; Gruneberg and Sykes 1978) you know you know the answer to a question—that is, you are familiar with it—but you can not retrieve it. This effect is especially annoying when it occurs when one is taking an exam or playing a game. The reverse situation can also be shown to occur. People may have no consciously retrievable memory of learning, for example, a list of words, but will relearn the words faster than if they had never learned them in the first place (Nelson 1978).