Rupert Sheldrake - Experiments on the Sense of Being Stared At (2001)(1).pdf

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Journal of the Society for Psychical Research Vol. 65, pp.122-137 (2001)
EXPERIMENTS ON THE SENSE OF BEING STARED AT:
THE ELIMINATION OF POSSIBLE ARTEFACTS
by RUPERT SHELDRAKE
INTRODUCTION
The feeling of being stared at from behind is very well known. Surveys in Europe and
North America have shown that between 70 and 97% of the population have experienced
it (Braud, Shafer & Andrews, 1990; Sheldrake, 1994; Cottrell, Winer & Smith, 1996).
For many years this phenomenon was surprisingly neglected by psychical researchers,
and experimental investigations were few and far between. Nevertheless, most studies
gave statistically significant positive results indicating that people really could tell when
they were being looked at from behind (for reviews see Braud, Shafer & Andrews,
1993a; Sheldrake, 1994). Recent studies have also given significant positive results.
Two kinds of experiment have been carried out. In the first, in a randomized series of
trials the subjects were looked at directly, or not looked at, and for each trial guessed
whether they were being looked at or not (Sheldrake,1994, 1998, 1999, 2000a). Their
guesses were either right or wrong. (In this context the term "guess" is used for want of a
better way of describing the process the subjects employed in trying to detect the lookers'
influence.)
In the second kind of experiment, subjects were viewed through closed circuit television
(CCTV) by a looker in a different room, and could not have received any clues about
when they were being looked at through normal sensory channels.. In these CCTV
experiments, the subjects did not have to make any conscious guesses; their reactions
were measured automatically by recording their galvanic skin response (GSR), as in lie-
detector tests (Braud, Shafer & Andrews 1990, 1993a, 1993b; Schlitz & LaBerge, 1994,
1997).
A great advantage of simple experiments in which subjects make conscious guesses is
that they enable many more people to take part in this research than the CCTV method.
They are also closer to the real-life phenomenon, and permit a range of investigations of
different variables that affect the sensitivity of subjects or the effectiveness of starers.
These experiments have again and again shown a characteristic pattern whereby the
scores in the looking trials are very significantly above the chance level, whereas in the
control not-looking trials the scores are not significantly different from chance
(Sheldrake, 1998, 1999, 2000a).
This pattern makes sense if people really do have a sense of being stared at from behind.
The sense would be expected to operate when they are indeed being stared at. By
contrast, in the control trials, the subjects are being asked to detect the absence of a stare,
which is a unnatural request with no parallel in real-life conditions, so it is not surprising
that their guesses were at chance levels. This characteristic pattern also implies that the
results of the trials are not simply a matter of cheating, subtle cues, implicit learning or
errors in recording the data. These possible sources of error should have affected scores
in both looking and not-looking trials.
Many people familiar with the field of psychical research, proponents and sceptics alike,
find it difficult to believe that a seemingly 'paranormal' phenomenon can be investigated
meaningfully by such simple and inexpensive methods, and that these experiments can
give repeatable positive results. It all seems too good to be true, and arouses the
suspicion that more or less subtle artefacts must underlie this effect. If so, what could
they be?
The most important potential problems are as follows:
1) Peeping or peripheral vision. This seems unlikely because it is not possible to
see someone sitting directly behind, and if the head were turned sufficiently to
do so the movement of the head would be obvious. Nevertheless, this possibility
needed to be tested experimentally, and in one of the experiments reported in
this paper I did this by comparing the performance of subjects with and without
blindfolds. If peeping or peripheral vision were involved, the use of blindfolds
should reduce or eliminate it.
2) Auditory or olfactory clues. The subjects might hear the lookers moving their
heads, or hear differences in their breathing, or hear paper rustling when they
turned away, or even detect different smells depending on which way they were
facing and breathing. These possibilities have been tested in a series of
experiments in which lookers and subjects were separated by closed windows.
The fact that there was still a still a significant positive effect showed that sounds
and smells could not explain the phenomenon (Sheldrake, 2000a). The CCTV
experiments also eliminated the possibility of such sensory clues.
3) Implicit learning. In trials in which feedback is given, subjects could learn to
respond to subtle sensory clues or to any patterns present in the trial
randomization. If so, then these forms of learning should not take place when
subjects are not given feedback. One of the experiments reported in this paper
was designed to investigate the effects of feedback by comparing the
performance of subjects with and without it.
4) Cheating. The lookers might whisper or in some other way signal to the
subjects whether they were looking or not looking. This possibility was tested
and eliminated by separating lookers and subjects by closed windows
(Sheldrake, 2000a), and it was also eliminated in the CCTV experiments.
5) Faults in recording the responses. The lookers could have made mistakes in
writing down the subjects' responses. This is a general problem with any kind of
research in which recording is done by human observers, rather than a specific
problem with staring experiments. Although careful supervision of the lookers
can reduce this possibility, perhaps it cannot eliminate it altogether. On the other
hand, in experiments such as these, recording errors would not be expected to
have a differential effect in test and control trials, such as those repeatedly
observed in experiments of this kind. In the CCTV trials, the records of GSR
were made automatically and hence would not have been subject to human
recording errors.
6) Experimenter effects. These could play a part when experimenters themselves
serve as lookers, especially if they expect their stares to be ineffective. Their
negative expectations might influence the way they stare, for example by
reducing their concentration. Under these conditions experimenter expectancy
effects are not only probable, but have actually been shown to occur, as
discussed below.
Experimenter Effects
Although most experiments both with direct staring and through CCTV have given
significant positive results, a few have failed to detect the staring effect, notably those
carried out by sceptics when the sceptics themselves acted as the lookers. Even sceptics
have obtained significant positive results when students served as lookers. </p><p>
In initial experiments on the sense of being stared at carried out in the laboratory of
Richard Wiseman, students acted as lookers. But in these experiments, instead of
looking at a single subject, the lookers were looking at two subjects, thus dividing their
attention (Wiseman & Smith, 1994). Nevertheless, in a series of CCTV experiments
there was a significant difference in the subjects' skin resistance in the looking and not-
looking trials (p<0.04).
Wiseman & Smith (1994) tried to explain this positive result as an artefact. They found
that in their randomization, more looking trials preceded not-looking trials than vice
versa. They argued that this could have given rise to an artefactual positive result if
subjects' galvanic skin resistance (GSR) declined throughout the session as they became
more relaxed. Apparently they did not examine their data to see if this was in fact the
case, but concluded anyway that their positive result was "almost certainly" artefactual
(Wiseman & Smith, 1994). They recommended that in future research of this kind, rather
than truly random sequences, counterbalanced sequences with equal numbers of staring
and not-staring trials should be used to avoid possible artefacts of this kind.
I asked Wiseman and Smith if I could examine their data to test their hypothesis. They
told me that some of the data were inaccessible, but kindly supplied me with the data for
17 out of 30 subjects, which I examined to see if in fact GSR had declined throughout the
sessions, as they had speculated. In 10 cases it declined, while in 7 it increased. If a
general trend of decreasing GSR gave rise to artefactual positive scores when more
looking trials preceded not-looking trials, in the subjects where GSR increased there
should have been an opposite effect. I found that this was not the case. At least for this
available subset of the data, the facts do not support Wiseman and Smith's speculation.
The positive results in this CCTV experiment were obtained with students as lookers. In
subsequent CCTV experiments in Wiseman's laboratory, the experimenters themselves
acted as lookers, and then there were no significant positive effects (Wiseman et al.,
1995). Under these conditions there could well have been scope for experimenter
effects, biassing the results in the direction of the experimenters' expectations. Such
experimenter expectancy effects are well known in psychological and parapsychological
research (e.g. Rosenthal, 1976; Palmer, 1989a, b).
The possibility of experimenter effects in staring experiments has been tested directly by
Wiseman & Schlitz (1997), who jointly carried out a CCTV staring experiment in which
half the subjects were tested with Schlitz as looker, and half with Wiseman. As on
previous occasions, Schlitz obtained significant positive results (Schlitz & LaBerge,
1994, 1997), while Wiseman's were non-significant.
The implications of these experimenter effects are not symmetrical. A sceptic could well
obtain a non-significant result in accordance with his negative expectations, for example
by not concentrating on the subject, but someone with positive expectations could not
cause subjects to obtain positive scores by any normal means when all possibilities of
sensory information transfer were excluded, as they were in these experiments.
Recently Colwell, Schröder & Sladen (2000) carried out a staring experiment following
similar methods to my own, using randomized sequences I had published on my world
wide web site (www.sheldrake.org). In their experiment, the lookers and subjects were
separated by a one-way mirror. As in my own tests, in a randomized series of trials, the
looker either looked at the back of the subjects' necks, or looked away and thought of
something else. The subjects guessed after each trial whether they had been looked at or
not.
In the first experiment, Schröder, a graduate student, was the looker. Over nine sessions
in which the subjects were given feedback as to whether their guesses were correct or not,
the results were positive and statistically significant (p<0.001). The pattern of results was
very similar to that in my own experiments (Sheldrake, 1998, 1999, 2000a), with a highly
significant excess of correct guesses in the looking trials, and guesses at chance levels in
the control trials, when the subjects were not looked at. There was, moreover, an
increasing accuracy as the subjects were tested repeatedly, with a significant linear trend
(p < 0.003).
Like Wiseman & Smith (1994), Colwell et al. (2000) attempted to explain their positive
result as an artefact of the randomization procedure. They argued that rather than
supporting the possibility that people really can feel stares, their participants' positive
scores were an artefact that arose from "the detection and response to structure" present in
my randomized sequences. And indeed the sequences they took from my world wide web
site were not "structureless". Ironically, this was the case because I adopted the
recommendation of Wiseman & Smith (1994) to use counterbalanced sequences with
equal numbers of looking and not-looking trials.
The crux of Colwell et al.'s argument was that because of the deviations from
"structureless" randomness in my sequences, participants could have implicitly learned to
detect patterns, for example that there was a relatively high probability of an alternation
after "two of a kind". But they offered no evidence that their participants in fact learned
to follow such rules. They could have examined the trial-by-trial scores to see if there
actually was an excess of successful guesses after two of a kind, or after any other
pattern they chose to postulate. Instead, they offered no more than a speculation that this
might have been the case.
The arguments of Colwell et al. (2000) were reiterated in a simplified form in an article
in The Skeptical Inquirer by Marks Marks & Colwell (2000), who failed to mention a
fundamental flaw in this hypothesis of pattern-detection through implicit learning. The
problem is this. Implicit learning should in principle enable participants to improve
equally in looking and not-looking trials. But this is not what happened. Significant
improvements occurred only in the looking trials (Colwell et al., 2000). So how could
implicit learning work in looking trials, but not at all in not-looking trials?
Colwell et al. (2000) recognized this problem, but could only suggest that participants
may have "focused more on the detection of staring than non-staring episodes." This
begs the question. The subjects must have selectively detected when staring trials were
happening, otherwise their scores would not have been above chance levels and shown
such an improvement in successive sessions. But this effect could well have occurred
because they really could detect when they were being stared at.
Colwell et al. (2000) did a second experiment to test their hypothesis using a
"structureless" randomization procedure and this time obtained non-significant results.
But in their discussion, as in Marks & Colwell's (2000), they omitted to mention that in
their second experiment there was not only a different randomization procedure, but also
a different looker, David Sladen. As one of the proponents of the pattern-detection
hypothesis, Sladen was presumably expecting a non-significant result. His negative
expectations may well have influenced the way in which he stared at the participants. It
would be interesting to know if Sadi Schröder, the graduate student who acted as starer in
their first experiment, was more open-minded about the possibility that people really
could detect stares.
Thus the difference between the results of Colwell et al.'s first and second experiments
could well be have been due to an experimenter effect, rather than to differently
randomized test sequences.
Colwell et al. (2000) and Marks & Colwell (2000) used the results of this second
experiment to suggest that my own findings in staring experiments were an artefact due
to implicit learning of structures present in the counterbalanced randomized sequences. If
my experiments had involved feedback, as required by their hypothesis, this criticism
might have been relevant. But this is not how the tests were done. </p><p>
In more than five thousand of my own trials, the randomization was indeed
"structureless", and was carried out by each starer before each trial by tossing a coin
(Sheldrake 1999, Tables 1 and 2). The same was true of more than 3,000 trials in
German and American schools (Sheldrake 1998). Thus the highly significant positive
results in these experiments cannot be "an artifact of pseudo randomization", as Marks
and Colwell (2000) suggested.
When I developed the counterbalanced sequences, I changed the experimental design so
that feedback was no longer given to the subjects. Since the pattern-detection hypothesis
depends on feedback, it cannot account for the fact that in more than 10,000 trials without
feedback there were still highly significant positive results (Sheldrake 1999, Tables 3 and
4).
Finally, in another recent paper in The Skeptical Inquirer Baker (2000) reported that in a
staring experiment (through a one-way mirror) with himself as the starer the results were
non- significant. Baker made no secret of his sceptical attitude and indeed regarded his
experiment not so much as a test as a "demonstration" of the non-existence of an ability
to detect stares. In addition to the likelihood of a strong experimenter effect, his
experimental design was seriously flawed. His instructions to his subjects were
confusing, ambiguous and (at least in their published form) contained serious errors, as he
now recognizes (Sheldrake, 2000b).
By contrast with these experiments carried out by sceptics, the positive and highly
significant results in the far larger number of experiments carried out by other
investigators and by myself have involved hundreds of different people acting as lookers,

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