Remote Perception at Stanford Research Institute

2008-07-10 8:46

The Stanford Research Institute conducted experiments on Uri Geller's abilities. This video summarizes the findings; you can find the full scientific paper produced below.



Text for narration of SRI film entitled "Experiments with Uri Geller"





Throughout mankind's history there has existed a folklore that certain gifted individuals have been capable of producing physical effects by means of some agency generally referred to as psychic or psychoenergetic. Substantiation of such claims by accepted scientific methodology has been slow in coming, but recent laboratory experiments, especially in the Soviet Union and Czechoslovakia, and more recently in our own laboratory, have indicated that sufficient evidence does exist to warrant serious scientific investigation. It would appear that experiments could be conducted with scientific rigor to uncover not just a catalog of interesting events, but rather a pattern of cause-effect relationships of the type that lend themselves to analysis and hypothesis in the forms with which we are familiar in the physical sciences. SRI considers this to be a valid area for scientific inquiry.
As scientists we consider it important to examine various models describing the operation of these effects so that we can determine the relationship between extraordinary human functioning and the physical and psychological laws we presently understand. It is not the purpose of our work at SRI to add to the literature another demonstration of the statistical appearance of these phenomena in the laboratory, but rather we seek to achieve an understanding more compatible with contemporary science, and more useful to mankind.
This film describes a 5-week investigation conducted at Stanford Research Institute with Uri Geller, a young Israeli. The film portrays experiments that we performed with him just as they were carried out. Each scene has been taken from film footage made during actual experiments; nothing has been restaged or specially created. It is not the purpose of the film to demonstrate any purported psychic abilities of Mr. Geller but rather to demonstrate the experiments done with him and his response to the experimental situation.
Meet Uri Geller. One of the types of demonstration that Geller likes to do is to sit with a group of people and attempt to send a number to various people in the room. With Uri Geller, this is Edgar Mitchell, who with his eyes covered is trying to pick up the number that Geller is sending. Also, we see Wilbur Franklin of Kent State, Harold Puthoff and Russell Targ of SRI, along with Don Scheuch, Vice President for research at SRI. Dr. Scheuch is trying to receive and then write down the number that Geller is sending. In this case, Scheuch is successful in picking up the number.
Of course, this is not a laboratory experiment, since the activity is totally under Geller's control. It was set as an absolute that experiments, to be worthy, had to be under Institute control. Here we show a series of experiments where, previously, 15 drawings were placed in double-sealed envelopes in a safe for which none of the experimenters had the combination. It took signatures of both the key researchers to remove a drawing at random from the collection in the safe. One of the researchers would then, in this case Targ, look at the drawing outside the experimental room, reseal the envelope, enter the experimental room, whence Geller's task was to draw what he perceived in the envelope.
This is Geller's representation of what he believed was sealed in the envelope. At no time during these experiments did he have any advance knowledge of the target material. As far as he is concerned, these could be drawings of any kind, whether a design or a representational picture. In fact, this is the most off-target of the drawings that he did.
Here -- the experiment is repeated, this time with Puthoff as a sender, just to check that the identity of the sender is of no significance in the experiment. Additionally, all experiments are tape recorded to guard against any verbal cueing on the part of the experimenters.
This is the drawing that Geller has made to correspond to the target object. The rectangle on the clip-board represents the TV screen in Geller's mind on which he claims to project the image he is trying to draw. As you can see, he is quite elated about getting the right answer. Before he does this, it is usually preceded by several minutes of "I can't do this--it's impossible. I want to stop, Let's wait."
Here in the laboratory notebook on the left side of the page you see the original targets, and on the right, Geller's responses. This is not a collection of correct answers out of a long series of correct and incorrect responses. This is actually the total run of pictures in the series. It is interesting that there is often a mirror symmetry.
In this particular case. neither Geller nor the experimenter had knowledge of what the target was. This is a double blind experiment. Here, on the upper left of the page is a picture that was brought to SRI by an outside consultant and sealed in his own envelope; Geller's representation is at the lower right. This was by far the most complicated target picture encountered during these experiments.
This is a typical target carrier used in the experiments. The inner envelope is opaque in its own right; the outer one is a heavy manilla envelope. A flood light behind these envelopes would not permit the interior to be seen. This type of communication experiment was repeated many other times during the 5 weeks, with Geller choosing to pass about 20 percent of the time.
It is interesting that when he drew his response in this case he didn't recognize the object as eye glasses - - it seemed to him to be an abstract drawing. In general, these drawing experiments were not double blind as one of the experimenters know what was in the picture in the envelope.
Here, however, we present a case of a double blind experiment, in which someone not associated with the project comes in to the experimental room, places an object into a can chosen at random from ten aluminum cans. Numbered tops are also put on at random. The randomizer then leaves the area, and the experimenters enter the experimental area with Geller, with neither the experimenters nor Geller knowing which can contains the object. In this particular case, the target is a 3/4" steel ball which now resides in one of the 10 cans in the box.
The ten cans having been arranged neatly, Geller's task now is to determine which of these ten cans holds the steel ball bearing. He is not permitted to touch the cans or the table. The experimental protocol is for experimenter to remove the cans one at a time in response to Geller's instructions as he points or calls out a can-top number. Eventually, there will be just two or three cans left, and Geller will then indicate both by gesture and in writing which one of the remaining cans contains the target. It is only at the end of the experiment that Geller touches the can that he believes contains the object. The protocol included the possibility that he might touch a can accidentally. In such case, that would have counted as a miss. Here he writes the selected number.
This, you might say, is a kind of ten-can Russian roulette. He has made his choice. The steel ball is found.
In later repetitions of this same experiment, he was finally weaned away from the dousing technique where he runs his hands over the cans. He got to the point where he could walk into a room, see the cans lined up on a blackboard sill, and just pick up the one that contained the target. We have no hypothesis at this point as to whether this is a heightened sensitivity of some normal sense, or whether it is some paranormal sense.
Now we are repeating the experiment with a different target object. One of these cans is filled with room-temperature water. Again, the can was filled by an outside person who randomized the position of the cans.
Then the box that contained the cans was rotated by a second person so that there is no one person in the room who knows the location of the target can. As you can see here, there is 1ess hand motion by Geller over the can. The protocol as before involves his calling out the number or pointing and one of the experimenters removing the can at Geller's call. At this point in time he is asked to make his choice both by writing the number down as well as making a selection by hand. You will note that he is making a final test to be sure of his selection. Tentatively, he reaches and having made the selection now looks to see whether water is inside the can. He now waters the plant with the contents of the can. You will note, he is very pleased with finding this target because he had doubts at the outset whether he would be able to locate a can filled with water.
We repeated this type of experiment 14 times; 5 times involved a target being a small permanent magnet, 5 times also involved a steel ball bearing as the target. Twice the target was water. Two additional trials were made--one with a paper-wrapped ball bearing, and one with a sugar cube. The latter two targets were not located. Geller felt that he didn't have adequate confidence as to where they were, and he declined to guess, and passed. On the other 12 targets--the ball bearing, the magnet and the water - -he did make a guess as to the target location and was correct in every instance. In subsequent work with another subject, we found the subject experiencing a highly significant difference in his ability to find the steel ball bearing as compared with finding other targets.
The whole array of this run had an a priori probability of 1 part in 10^12 or statistics of a trillion to one. Here is another double blind experiment in which a die is placed in a metal file box (both box and die being provided by SRI). The box is shaken up with neither the experimenter nor Geller knowing where the die is or which face is up. This is a live experiment that you see- -in this case, Geller guessed that a four was showing but first he passed because he was not confident. You will note he was correct and he was quite pleased to have guessed correctly, but this particular test does not enter into our statistics.
The previous runs of 10-can roulette gave a result whose probability due to chance alone is one part in 10^12 We decided at the outset to carry out the die-in-box experiment until we got to a million to one odds, at which time the experiment was terminated. Out of 10 tries in which he passed twice and guessed eight times, the eight guesses were correct, and that gave us a probability of about one in a million.
We would point out again, there were no errors in the times he made a guess.
This is the first of two experiments in psychokinesis. Here a one- gram weight is being placed on an electrical scale. It is then covered by an aluminum can and by a glass cylinder to eliminate deflection due to air currents. The first part of our protocol involves tapping the bell jar; next tapping the table; then kicking the table; and finally jumping on the floor, with a record made of what these artifacts looked like so that they could be distinguished from signals. In tests following this experimental run, a magnet was brought near the apparatus, static electricity was discharged against parts of the apparatus, and controlled runs of day-long operation were obtained. In no case were artifacts obtained which in any way resembled the signals produced by Geller, nor could anyone else duplicate the effects.
The bottom four signals show the type of artifact that results from tapping or kicking the table. They are small AC signals with a time constant characteristic of the apparatus. The upper two traces, on the other hand, are apparently due to Geller's efforts. They are single-sided signals, one corresponding to a 1500 mg weight decrease, the other corresponding to an 800 mg weight increase. Those types of single-sided signals were never observed as artifacts with any other stimuli.
We have no ready hypothesis on how these signals might have been produced. The width of the signals produced by Geller was about 200 milliseconds. The chart ran at one millimeter per second. It was of interest to note that Geller's performance improved over the period of experimentation, starting with 50 mg deflections and arriving at 1500 mg.
In this experiment Geller is attempting to influence the magnetometer either directly or by generating a magnetic field. The full scale sensitivity of the instrument is .0.3 of a gauss, and, as is clear in this instance, his hands are open. Throughout the experiment, his hands do not come into contact with the instrument. The magnetometer itself was used as a probe to go over his hands and person to make sure that there were no magnetic objects in his hands or on him. Here you see substantial fluctuations both to the left and to the right--almost full scale--in certain cases -- on the magnetometer meter. These fluctuations are sometimes uncorrelated with the motions of his hands.
This is the chart recording of the magnetometer fluctuations produced by Geller. We see here full scale fluctuations of 0.3 of a gauss which is a significant magnetic field, comparable to the earth's field. After each of these experiments we would in general discuss the results with Geller, show him the strip chart recording, and talk about the significance of his experiments. He was very interested in the experiments we were doing because he had never taken part in laboratory experiments of this kind before.
The following is an experiment which in retrospect we consider unsatisfactory as it didn't meet our protocol standards. Here the task is to deflect the compass needle which, indeed, Geller does. Before and after the experiment, he was gone over with a magnetometer probe and his hands were photographed from above and below during and following the experiment so that we are sure there were no obvious pieces of metal or magnets in his possession. However, according to our protocol, if we could in any way debunk the experiment and produce the effects by any other means, then that experiment was considered null and void even if there were no indications that anything untoward happened. In this case, we found later that these types of deflections could be produced by a small piece of metal, so small in fact that they could not be detected by the magnetometer. Therefore, even though we had no evidence of this, we still considered the experiment inconclusive and an unsatisfactory type of experiment altogether.
A look at the lower mirror affords one the best view. It can be seen that his hands are completely exposed to photography from above and below with different cameras.
These are a series of unconfirmed physical effects that need further investigation. One of Geller's main attributes that had been reported to us was that he was able to bend metal from a distance without touching it. In the laboratory we did not find him able to do so. In a more relaxed protocol, he was permitted to touch the metal, in which case, as you will see in the film, the metal is indeed bent. However, it becomes clear in watching this demonstration on film that simple photo interpretation is unsufficient to determine whether the metal is bent by normal or paranormal means.
In the laboratory, these spoon bending experiments were continuously filmed and videotaped. It is evident that some time during the photographic period this stainless steel spoon became bent. However, unlike the things we have heard about Geller, it was always necessary for him in the experimental situation to have physical contact with the spoon or for that matter any other object that he bends. It is not clear whether the spoon is being bent because he has extraordinarily strong fingers and good control of micro-manipulatory movements or whether, in fact, the spoon "turns to plastic" in his hands, as he claims.
Here are a number of the spoons that were bent by one means or another during the course of our experiments. There is no doubt that the spoons were bent. The only doubt remains as to the manner of their bending. Similarly, we have rings that were bent by Mr. Geller. The rings that were bent are shown here. The copper ring at the left and the brass ring at the right were manufactured at SRI and measured to require 150 lbs force to bend them. These rings were in Geller's hand at the time they were bent.
This brief recap is to remind you of those experiments we feel were best controlled. They are the three perception experiments, including the hidden drawings in envelopes, the double-blind hidden object experiments, and the double - blind die in the box experiment. The two psychokinetic experiments --the depression or raising of a weight on an electrical scale and the deflection of the magnetometer -- also do not seem to admit of any ready counter hypothesis. What we've demonstrated here are the experiments that we performed in the laboratory and should not be interpreted as proof of psychic functioning. Indeed, a film never proves anything. Rather, this film gives us the opportunity to share with the viewer observations of phenomena that in our estimation clearly deserve further study.


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SRI's Official Scientific Paper


We present results of experiments suggesting the existence of one or more perceptual modalities through which individuals obtain information about their environment, although this information is not presented to any known sense. The literature 1-3 and our observations lead us to conclude that such abilities can be studied under laboratory conditions.

We have investigated the ability of certain people to describe graphical material or remote scenes shielded against ordinary perception. In addition, we performed pilot studies to determine if electroencephalographic (EEG) recordings might indicate perception of remote happenings even in the absence of correct overt responses.

We concentrated on what we consider to be our primary responsibility -- to resolve under conditions as unambiguous as possible the basic issue of whether a certain class of paranormal perception phenomena exists. So we conducted our experiments with sufficient control, utilising visual, acoustic and electrical shielding, to ensure that all conventional paths of sensory input were blocked. At all times we took measures to prevent sensory leakage and to prevent deception, whether intentional or unintentional.

Our goal is not just to catalogue interesting events, but to uncover patterns of cause-effect relationships that lend themselves to analysis and hypothesis in the forms with which we are familiar in scientific study. The results presented here constitute a first step towards that goal; we have established under known conditions a data base from which departures as a function of physical and psychological variables can be studied in future work.

First, we conducted experiments with Mr. Uri Geller in which we examined his ability, while located in an electrically shielded room, to reproduce target pictures drawn by experimenters located at remote locations. Second, we conducted double-blind experiments with Mr. Pat Price, in which we measured his ability to describe remote outdoor scenes many miles from his physical location.

Finally, we conducted preliminary tests using EEGs, in which subjects were asked to perceive whether a remote light was flashing, and to determine whether a subject could perceive the presence of the light, even if only at a noncognitive level of awareness.

In preliminary testing Geller apparently demonstrated an ability to reproduce simple pictures (line drawings) which had been drawn and placed in opaque sealed envelopes which he was not permitted to handle. But since each of the targets was known to at least one experimenter in the room with Geller, it was not possible on the basis of the preliminary testing to discriminate between Geller's direct perception of envelope contents and perception through some mechanism involving the experimenters, whether paranormal or subliminal. So we examined the phenomenon under conditions designed to eliminate all conventional information channels, overt or subliminal. Geller was separated from both the target material and anyone knowledgeable of the material, as in the experiments of ref. 4.

In the first part of the study a series of 13 separate drawing experiments were carried out over 7 days. No experiments were deleted from the results presented here.

At the beginning of the experiment either Geller or the experimenters entered a shielded room so that from that time forward Geller was at all times visually, acoustically, and electrically shielded from personnel and material at the target location. Only following Geller's isolation from the experimenters was a target chosen and drawn, a procedure designed to eliminate pre-experiment cueing. Furthermore, to eliminate the possibility of pre-experiment target forcing, Geller was kept ignorant as to the identity of the person selecting the target and as to the method of target selection. This was accomplished by the use of three different techniques: (1) pseudo-random technique of opening a dictionary arbitrarily and choosing the first word that could be drawn (Experiments 1-4); (2) targets, blind to experimenters and subject, prepared independently by SRI scientists outside the experimental group (following Geller's isolation) and provided to the experimenters during the course of the experiment (Experiments 5-7, 11-13); and (3) arbitrary selection from a target pool decided upon in advance of daily experimentation and designed to provide data concerning information content for use in testing specific hypotheses (Experiments 8-10). Geller's task was to reproduce with pen on paper the line drawing generated at the target location. Following a period of effort ranging from a few minutes to half an hour, Geller either passed (when he did not feel confident) or indicated he was ready to submit a drawing to the experimenters, in which case the drawing was collected before Geller was permitted to see the target.

To prevent sensory cueing of the target information, Experiments 1 through 10 were carried out using a shielded room in SRI's facility for EEG research. The acoustic and visual isolation is provided by a double-walled steel room, locked by means of an inner and outer door, each of which is secured with a refrigerator-type locking mechanism. Following target selection when Geller was inside the room, a one-way audio monitor, operating only from the inside to the outside, was activated to monitor Geller during his efforts. The target picture was never discussed by the experimenters after the picture was drawn and brought near the shielded room. In our detailed examination of the shielded room and the protocol used in these experiments, no sensory leakage has been found.

The conditions and results for the 10 experiments carried out in the shielded room are displayed in Table 1 and Fig. 1. All experiments except 4 and 5 were conducted with Geller inside the shielded room. In Experiments 4 and 5, the procedure was reversed. For those experiments in which Geller was inside the shielded room, the target location was in an adjacent room at a distance of about 4 m, except for Experiments 3 and 8, in which the target locations were, respectively, an office at a distance of 475 m and a room at a distance of about 7 M.

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A response was obtained in all experiments except Numbers 5-7. In Experiment 5, the person-to-person link was eliminated by arranging for a scientist outside the usual experimental group to draw a picture, lock it in the shielded room before Geller's arrival at SRI, and leave the area. Geller was then led by the experimenters to the shielded room and asked to draw the picture located inside the room. He said that he got no clear impression and therefore did not submit a drawing. The elimination of the person-to-person link was examined further in the second series of experiments with this subject.

Experiments 6 and 7 were carried out while we attempted to record Geller's EEG during his efforts to perceive the target pictures. The target pictures were, respectively, a tree and an envelope. He found it difficult to hold adequately still for good EEG records, said that he experienced difficulty in getting impressions of the targets, and again submitted no drawings.

Experiments 11 through 13 were carried out in SRI's Engineering Building, to make use of the computer facilities available there. For these experiments, Geller was secured in a double-walled, copper-screen Faraday cage 54 m down the hall and around the corner from the computer room. The Faraday cage provides 120 dB attenuation for plane wave radio frequency radiation over a range of 15 kHz to 1 GHz. For magnetic fields the attenuation is 68 dB at 15 kHz and decreases to 3 dB at 60 Hz. Following Geller's isolation, the targets for these experiments were chosen by computer laboratory personnel not otherwise associated with either the experiment or Geller, and the experimenters and subject were kept blind as to the contents of the target pool.

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For Experiment 11, a picture of a kite was drawn on the face of a cathode ray tube display screen, driven by the computer's graphics programme. For Experiment 12, a picture of a church was drawn and stored in the memory of the computer. In Experiment 13, the target drawing, an arrow through a heart (Fig. 2c), was drawn on the face of the cathode ray tube and then the display intensity was turned off so that no picture was visible.

To obtain an independent evaluation of the correlation between target and response data, the experimenters submitted the data for judging on a 'blind' basis by two SRI scientists who were not otherwise associated with the research. For the 10 cases in which Geller provided a response, the judges were asked to match the response data with the corresponding target data (without replacement). In those cases in which Geller made more than one drawing as his response to the target, all the drawings were combined as a set for judging. The two judges each matched the target data to the response data with no error. For either judge such a correspondence has an a priori probability, under the null hypothesis of no information channel, of p 1/(10!) = 3 x 10 to the power -7.

A second series of experiments was carried out to determine whether direct perception of envelope contents was possible without some person knowing of the target picture.

One hundred target pictures of everyday objects were drawn by an SRI artist and sealed by other SRI personnel in double envelopes containing black cardboard. The hundred targets were divided randomly into groups of 20 for use in each of the three days' experiments. On each of the three days of these experiments, Geller passed. That is, he declined to associate any envelope with a drawing that he made, expressing dissatisfaction with the existence of such a large target pool. On each day he made approximately 12 recognisable drawings, which he felt were associated with the entire target pool of 100. On each of the three days, two of his drawings could reasonably be associated with two of the 20 daily targets. On the third day, two of his drawings were very close replications of two of that day's target pictures. The drawings resulting from this experiment do not depart significantly from what would be expected by chance.

In a simpler experiment Geller was successful in obtaining information under conditions in which no persons were knowledgeable of the target. A double-blind experiment was performed in which a single 3/4 inch die was placed in a 3 x 4 x 5 inch steel box. The box was then vigorously shaken by one of the experimenters and placed on the table, a technique found in control runs to produce a distribution of die faces differing nonsignificantly from chance. The orientation of the die within the box was unknown to the experimenters at that time. Geller would then write down which die face was uppermost. The target pool was known, but the targets were individually prepared in a manner blind to all persons involved in the experiment. This experiment was performed ten times, with Geller passing twice and giving a response eight times. In the eight times in which he gave a response, he was correct each time. The distribution of responses consisted of three 2s, one 4, two 5s, and two 6s. The probability of this occurring by chance is approximately one in 10 to the power 6.

In certain situations significant information transmission can take place under shielded conditions. Factors which appear to be important and therefore candidates for future investigation include whether the subject knows the set of targets in the target pool, the actual number of targets in the target pool at any given time, and whether the target is known by any of the experimenters.

It has been widely reported that Geller has demonstrated the ability to bend metal by paranormal means. Although metal bending by Geller has been observed in our laboratory, we have not been able to combine such observations with adequately controlled experiments to obtain data sufficient to support the paranormal hypothesis.

A study by Osis 5 led us to determine whether a subject could describe randomly chosen geographical sites located several miles from the subject's position and demarcated by some appropriate means (remote viewing). This experiment carried out with Price, a former California police commissioner and city councilman, consisted of a series of double-blind, demonstration-of-ability tests involving local targets in the San Francisco Bay area which could be documented by several independent judges. We planned the experiment considering that natural geographical places or man-made sites that have existed for a long time are more potent targets for paranormal perception experiments than are artificial targets prepared in the laboratory. This is based on subject opinions that the use of artificial targets involves a 'trivialisation of the ability' as compared with natural preexisting targets.

In each of nine experiments involving Price as subject and SRI experimenters as a target demarcation team, a remote location was chosen in a double-blind protocol. Price, who remained at SRI, was asked to describe this remote location, as well as whatever activities might be going on there.

Several descriptions yielded significantly correct data pertaining to and descriptive of the target location.

In the experiments a set of twelve target locations clearly differentiated from each other and within 30 minutes driving time from SRI had been chosen from a target-rich environment (more than 100 targets of the type used in the experimental series) prior to the experimental series by an individual in SRI management, the director of the Information Science and Engineering Division, not otherwise associated with the experiment. Both the experimenters and the subject were kept blind as to the contents of the target pool, which were used without replacement.

An experimenter was closeted with Price at SRI to wait 30 minutes to begin the narrative description of the remote location. The SRI locations from which the subject viewed the remote locations consisted of an outdoor park (Experiments 1, 2),- the double-walled copper-screen Faraday cage discussed earlier (Experiments 3, 4, and 6-9), and an office (Experiment 5). A second experimenter would then obtain a target location from the Division Director from a set of traveling orders previously prepared and randomised by the Director and kept under his control. The target demarcation team (two to four SRI experimenters) then proceeded directly to the target by automobile without communicating with the subject or experimenter remaining behind. Since the experimenter remaining with the subject at SRI was in ignorance both as to the particular target and as to the target pool, he was free to question Price to clarify his descriptions. The demarcation team then remained at the target site for 30 minutes after the 30 minutes allotted for travel. During the observation period, the remote-viewing subject would describe his impressions of the target site into a tape recorder. A comparison was then made when the demarcation team returned.

Price's ability to describe correctly buildings, docks, roads, gardens, and so on, including structural materials, color, ambiance, and activity, sometimes in great detail, indicated the functioning of a remote perceptual ability. But the descriptions contained inaccuracies as well as correct statements. To obtain a numerical evaluation of the accuracy of the remote viewing experiment, the experimental results were subjected to independent judging on a blind basis by five SRI scientists who were not otherwise associated with the research. The judges were asked to match the nine locations, which they independently visited, against the typed manuscripts of the tape-recorded narratives of the remote viewer. The transcripts were unlabelled and presented in random order. The judges were asked to find a narrative which they would consider the best match for each of the places they visited. A given narrative could be assigned to more than one target location. A correct match requires that the transcript of a given date be associated with the target, of that date. Table 2 shows the distribution of the judges' choices.

Among all possible analyses, the most conservative is a permutation analysis of the plurality vote of the judges' selections assuming assignment without replacement, an approach independent of the number of judges. By plurality vote, six of the nine descriptions and locations were correctly matched. Under the null hypothesis (no remote viewing and a random selection of descriptions without replacement), this outcome has an a priori probability of p = 5.6 x 10 to the power -4 since, among all possible permutations of the integers one through nine, the probability of six or more being in their natural position in the list has that value. Therefore, although Price's descriptions contain inaccuracies, the descriptions are sufficiently accurate to permit the judges to differentiate among the various targets to the degree indicated.

An experiment was undertaken to determine whether a physiological measure such as EEG activity could be used as an indicator of information transmission between an isolated subject and a remote stimulus. We hypothesised that perception could be indicated by such a measure even in the absence of verbal or other overt indicators. 6, 7

It was assumed that the application of remote stimuli would result in responses similar to those obtained under conditions of direct stimulation. For example, when normal subjects are stimulated with a flashing light, their EEG typically shows a decrease in the amplitude of the resting rhythm and a driving of the brain waves at the frequency of the flashes 8. We hypothesised that if we stimulated one subject in this manner ( a sender), the EEG of another subject in a remote room with no flash present (a receiver), might show changes in alpha (9-11 Hz) activity, and possibly EEG driving similar to that of the sender.

We informed our subject that at certain times a light was to be flashed in a sender's eyes in a distant room, and if the subject perceived that event, consciously or unconsciously, it might be evident from changes in his EEG output. The receiver was seated in the visually opaque, acoustically and electrically shielded double-walled steel room previously described. The sender was seated in a room about 7 m from the receiver.

To find subjects who were responsive to such a remote stimulus, we initially worked with four female and two male volunteer subjects, all of whom believed that success in the experimental situation might be possible. These were designated 'receivers'. The senders were either other subjects or the experimenters. We decided beforehand to run one or two sessions of 36 trials each with each subject in this selection procedure, and to do a more extensive study with any subject whose results were positive.

A Grass PS-2 photostimulator placed about 1 m in front of the sender was used to present flash trains of 10 s duration. The receiver's EEG activity from the occipital region (0z), referenced to linked mastoids, was amplified with a Grass SP-1 preamplifier and associated driver amplifier with a bandpass of 1-120 Hz. The EEG data were recorded on magnetic tape with an Ampex SP 300 recorder.

On each trial, a tone burst of fixed frequency was presented to both sender and receiver, and was followed in one second by either a 10 s train off lashes or a null flash interval presented to the sender. Thirty-six such trials were given in an experimental session, consisting of 12 null trials - no flashes following the tone - 12 trials of flashes at 6 f.p.s. and 12 trials of flashes at 16 f.p.s., all randomly intermixed, determined by entries from a table of random numbers. Each of the trials generated an 11-s EEG epoch. The last 4 s of the epoch was selected for analysis to minimise the desynchronising action of the warning cue. This 4-s segment was subjected to Fourier analysis on a LINC 8 computer.

Spectrum analyses gave no evidence of EEG driving in any receiver, although in control runs the receivers did exhibit driving when physically stimulated with the flashes. But of the six subjects studied initially, one subject (H. H.) showed a consistent alpha blocking effect. We therefore undertook further study with this subject.

Data from seven sets of 36 trials each were collected from this subject on three separate days. This comprises all the data collected to date with this subject under the test conditions described above. The alpha band was identified from average spectra, then scores of average power and peak power were obtained from individual trials and subjected to statistical analysis.

Of our six subjects, H. H. had by far the most monochromatic EEG spectrum. Figure 3 shows an overlay of the three averaged spectra from one of this subject's 36-trial runs, displaying changes in her alpha activity for the three stimulus conditions.

Mean values for the average power and peak power for each of the seven experimental sets are given in Table 3. The power measures were less in the 16 f.p.s. case than in the 0 f.p.s. in all seven peak power measures and in six out of seven average power measures. Note also the reduced effect in the case in which the subject was informed that no sender was present (Run 3). It seems that overall alpha production was reduced for this run in conjunction with the subject's expressed apprehension about conducting the experiment without a sender. This is in contrast to the case (Run 7) in which the subject was not informed.

Siegell's two-tailed t approximation to the nonparametric randomisation test 9 was applied to the data from all sets, which included two sessions in which the sender was removed. Average power on trials associated with the occurrence of 16 f.p.s. was significantly less than when there were no flashes t = 2.09, d.f. = 118, P < 0.04). The second measure, peak power, was also significantly less in the 16 f. p. s. conditions than in the null condition ( t = 2.16, d.f. = 118, P < 0.03). The average response in the 6 f.p.s. condition was in the same direction as that associated with 16 f.p.s., but the effect was not statistically significant.

Spectrum analyses of control recordings made from saline with a 12 kOhm resistance in place of the subject with and without the addition of a 10 Hz, 50 microvolt test signal applied to the saline solution, revealed no indications of flash frequencies, nor perturbations of the 10 Hz signal. These controls suggest that the results were not due to system artifacts. Further tests also gave no evidence of radio frequency energy associated with the stimulus.

Subjects were asked to indicate their conscious assessment for each trial as to which stimulus was generated. They made their guesses known to the experimenter via one-way telegraphic communication. An analysis of these guesses has shown them to be at chance, indicating the absence of any supraliminal cueing. So, arousal as evidenced by significant alpha blocking occurred only at the noncognitive level of awareness.

We hypothesised that the protocol described here may prove to be useful as a screening procedure for latent remote perceptual ability in the general population.

From these experiments we conclude that:

- A channel exists whereby information about a remote location can be obtained by means of an as yet unidentified perceptual modality.
- As with all biological systems, the information channel appears to be imperfect, containing noise along with the signal.
- While a quantitative signal-to-noise ratio in the information-theoretical sense cannot as yet be determined, the results of our experiments indicate that the functioning is at the level of useful information transfer.

It may be that remote perceptual ability is widely distributed in the general population, but because the perception is generally below an individuals level of awareness, it is repressed or not noticed. For example, two of our subjects (H.H. and P.P.) had not considered themselves to have unusual perceptual ability before their participation in these experiments.

Our observation of the phenomena leads us to conclude that experiments in the area of so-called paranormal phenomena can be scientifically conducted, and it is our hope that other laboratories will initiate additional research to attempt to replicate these findings.

This research was sponsored by The Foundation for Parasensory Investigation, New York City.

We thank Mrs. Judith Skutch, Dr. Edgar D. Mitchell of the Institute of Noetic Sciences - as well as our SRI associates, Mr. Bonnar Cox, Mr. Earle Jones and Dr. Dean Brown - for support and encouragement. Constructive suggestions by Mrs. Jean Mayo, Dr. Charles Tart, University of California, and Dr. Robert Ornstein and Dr. David Galin of the Langley Porter Neuropsychiatric Institute are acknowledged.

Russell Targ

Harold Puthoff

Electronics and Bioengineering Laboratory, Stanford Research Institute, Menlo Park, California 94025

Fig 1. Target pictures and responses drawn by Uri Geller under shielded conditions.
Fig 2. Computer drawings and responses drawn by Uri Geller.
a, Computer drawing stored on video display;
b, computer drawing stored in computer memory only;
c, computer drawing stored on video display with zero intensity.
Fig 3. Occipital EEG spectra, 0-20 Hz, for one subject (H. H.) acting as receiver, showing amplitude changes in the 9-11 Hz band as a function of strobe frequency. Three cases: 0,6, and 16 f.p.s. (12 trial averages).

Tables

1 Pratt, J., Rhine, J.B., Stuart, C., and Greenwood, J., Extra Sensory Perception after Sixty Years (Henry Holt, New York, 1940).
2 Soal, S., and Bateman, F., Modern Experiments in Telepathy (Faber and Faber, London, 1954).
3 Vasilliev, L.L., Experiments in Mental Suggestion (ISMI Publications, Hampshire, England, 1963).
4 Musso, J.R., and Granero, M., J. Parapsychology, 37, 13-37 (1973).
5 Osis, K., ASPR Newsletter, No. 14 (1972).
6 Tart, C.T., Physiological Correlates of Psi Cognition, Int. J. Parapsychology, V, No. 4 (1963).
7 Dean, E.D., Int. J. Neuropsychiatry, 2 (1966).
8 Hill, D., and Parr, G., Electroencephalography: A Symposium on its Various Aspects (Macmillan, New York, 1963).
9 Siegel, S., Nonparametric Statistics for the Behavioural Sciences, pp. 152-156 (McGraw-Hill, New York, 1956).