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Déjà Vu...Again

A variety of polls in the United States show 80-90% of the population believes in ESP. Perhaps one reason for this high level of belief is that most people have personal experience with ESP.

A Glamour magazine survey found 90% of their readers believed in ESP. Most reported experiences of dreams that foretold exact details of a present situation.

What sorts of ESP-like experiences did readers of Glamour most often report and how might they be explained?

As pointed out in Chapter 2, this feeling of having predicted the present moment is an illusion caused by a temporal lobe discharge. It is the déjà vu sensation.

It feels much like a dream being remem­bered, so people unaware that déjà vu can originate from spontaneous activity in the temporal lobe naturally interpret the sensation as a dream coming true. The illusion is familiar to neurosurgeons who call them "dreamy sensations."

How do people explain déjà vu sensations to themselves?

Dreamy sensations are considered diagnostic of seizure-like activity in the temporal lobe or limbic system. Brain surgeon Foster Kennedy gave the following description:

The patient suddenly becomes aware of everything being changed, yet very familiar: a feeling of remini­scence, as though everything had happened before... The feeling of old-time familiarity is so acute that it seems as though it must be that he surely knows what is about to happen; what the next word in the conversation will be. (in Kahn & Crosby, 1969 p.49)

Psychologists have proposed various ad hoc explanations of déjà vu sensations. Theories involve interplay between different memory systems, or reverb­erating circuits, all very speculative.

There might be no rational explanation for a déjà vu sensation, any more than there are rational explanations for a random hiccup or eyebrow twitch. Sometimes neural circuits activate themselves.

Stressful situations make this more likely, the same way they make seizures more likely. During brain surgery, the sensations can be elicited by direct stimulation of the temporal lobe.

What is remarkable about déjà vu is the complex cognitive processing that takes place during a déjà vu sensation. Every detail of the present moment seems familiar. People often explain this to themselves by assuming they have dreamed the present moment.

If the feeling persists for a few seconds, people feel they are predicting each event as it happens. No wonder many people believe they have experienced episodes of precog­nition.

In a classroom survey, 95% of students in an introductory psychology class reported having déjà vu sensations, and 80% reported cases in which the exact details of a dream or a premonition have "come true."

My theory is that these two events are the same. Feelings of a dream coming true are typically déjà vu sensations inter­preted as dream memories.

How confirming details become part of the tale

Seizures can be triggered by tense situations. déjà vu sensations are probably mild epileptiform (seizure-like) events in the temporal lobe.

I started collecting reports of such events early in my teaching career. I found that many students had experiences that they classified as precognition rather than déjà vu.

They also remembered proof that that the dream had occurred such as discussing the dream with somebody else before the details of the dream came true. Now, that would be really remarkable, if it was documented, but it never was; it was always a retro­spective self-report, the least reliable form of data.

I suspect these memories of telling somebody about the dream are part of the déjà vu sensation itself, similar to what surgeons call déjà pensé. A déjà pensé sensation occurs when a new thought feels familiar, like a person has had the same thought before.

This is like the patient on the operating table who feels she can predict what the surgeon will do next. When a déjà pensé occurs, the logical interpretation (if a person does not know about temporal lobe discharges) is, "I have predicted this."

Here is how déjà pensé could interact with events of everyday life. Let's say the parents of a college student visiting home over vacation are having breakfast before the student gets up, discussing some bad news they just heard: Uncle Bill suffered a broken finger in a bicycle crash.

The college-age son or daughter comes down the stairs for breakfast and hears the bad news. A tiny area in the tempor­al lobe is activated. The student's eyes widen.

"Uncle Bill had a bicycle crash and broke his finger? I dreamed that exact thing! Then, a moment later, "And I remember telling you about that dream! Remember? I said I had dreamed Uncle Bill had a bicycle crash...

I have to assume the memory of having told somebody about the dream is part of the déjà vu sensation. It is confab­ulated, just like the memory of the dream. But it feels real, just the way déjà vu feels real.

What is Mom or Dad going to say at that moment? "I don't believe you!" or "You never told me about any such dream!" Not likely.

Instead, the parent will probably say. "Oh!" And from that point on, the story becomes a family legend involving not just precognition but indisputable proof of precognition.

The student (and soon everybody else) believes that (1) he or she had a dream that foretold Uncle Bill's crash and injury, in detail, and (2) the dream was report­ed to somebody else when it happened, before the accident. Therefore precognition is real.

To be sure, genuine predictions of bad events can happen. They can be based on common sense (like predicting somebody how likes texting while driving will have an accident). Predictions can be based on subtle cues such as shallow breathing in an elderly person (a predictor of death).

However, premonitions of extremely unlikely events (like Uncle Bill breaking a finger in a bicycle crash, or the plane you are about to board going down in flames) are different. Predictions like that hardly ever come true.

Potent Magic

I suggested to students a foolproof way to make an unpleasant premonition NOT come true. Write it down. Date it. Put it in an envelope or computer file addressed to yourself. Then the premonition is guaranteed not to come true.

This apparently works 100% of the time. What happens, if you do this, is that you find the envelope (or computer file) weeks, months, or years later. Open it, read it, and you will realize the feared event never happened.

Remember the event has to be inherently unlikely for this technique to work. Plausible premon­itions like "Our team will lose the champ­ionship" are not affected by this technique.

However, plane crashes and other worry-provoking but highly-unlikely events can be warded off with this procedure. It is potent magic!


Kahn, E. A., Crosby E. C., Schneider, R. C., & Taren, J. A. (Eds.) (1969) Correlative Neurosurgery, 2nd ed. Springfield, IL: Charles C Thomas.

Write to Dr. Dewey at

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