Date: Mon Oct 10 1994 13:41:30
From: John Powell
Psi in Psychology by Susan Blackmore
(The Skeptical Inquirer, Vol. 18, No. 4, Summer 1994, Copyright 1994 by
the Committee for the Scientific Investigation of Claims of the
Paranormal, 3965 Rensch Road, Buffalo, NY 14228, published quarterly
with a membership/subscription rate of $25/yr.)
"Most academic psychologists do not yet accept existence of
psi." So begins the abstract of an important new paper on
The claim is undoubtedly true, and many readers of SI will think
it ought to stay that way. Yet this quotation implies that the
psychologists in question might soon be changing their minds.
It comes, not from a tirade against the skepticism of academia
but from an article just published in one of psychology's most
prestigious academic journals, Psychological Bulletin.
Titled "Does Psi Exist? Replicable Evidence for an Anomalous
Process of Information Transfer," the article is by parapsychologist
Charles Honorton (who died in 1992 - see SI, 17:306-308, Spring 1993)
and Cornell psychologist Daryl Bem. Bem's high profile and the respect
he is accorded by psychologists will ensure that this article is taken
seriously and that perhaps some of them will begin to wonder about psi.
So how good is this "replicable evidence"? Is it sufficient, as
the authors claim, to suggest the existence of "anomalous processes of
information or energy transfer (like telepathy or other forms of
extrasensory perception) that are currently unexplained in terms of
known physical or biological mechanisms"?
The evidence in question is an overview of research on the
ganzfeld. This technique of partial sensory deprivation of subjects in
ESP experiments, pioneered by Honorton in the mid-1970s, produced the
great Ganzfeld Debate in the mid-1980s (Hyman 1985; Honorton 1985; see
also SI, 10:2-7, Fall 1985), and finally culminated in fully automated
testing procedures (Honorton et al. 1990). The paper reviews the various
meta-analyses of ganzfeld findings and, as Honorton has done before,
argues that obvious problems like multiple analysis, selective
reporting, and methodological flaws cannot be responsible for the high
replication rates. It then presents data from "11 new ganzfeld studies."
In 1988 the National Research Council produced a report on
enhanced human performance that included a highly negative conclusion on
parapsychology (Druckman and Swets 1988; see SI, 13:34-45, Fall 1988).
Bem and Honorton have some new light to cast on this report that might
seem out of place in an academic article. The NRC apparently solicited a
background paper from Harris and Rosenthal, and this paper noted the
impressive ganzfeld results. According to Bem and Honorton, the chair of
the NRC committee telephoned Rosenthal and asked him to delete this
section of the paper. Rosenthal refused to do so. But the section in
question did not appear in the final NRC report.
This is troubling indeed if it means that prejudice is coming
before genuine scientific inquiry. It serves more than anything to
highlight how difficult it is to stick to purely scientific issues in
this controversial arena.
Bem and Honorton also accuse the NRC report of not being an
independent examination of the ganzfeld because it was heavily based on
Ray Hyman's original critique. As for their own paper, I would say it
could also be misleading. The strength of some of Hyman's arguments is
not at all apparent and the impression is given that many laboratories
have found replicable effects.
This claim receives some support from Honorton's analysis, which
shows that the overall effect does not depend on just one or two labs.
Nevertheless, by far the greatest number of studies were contributed by
just two researchers. Out of 28 studies, Honorton contributed 5 and Carl
Sargent, at Cambridge, 9. So Sargent's are by far the largest number of
studies. However, I have shown (Blackmore 1987) that there were very
serious problems with nearly all of Sargent's ganzfeld studies. By
failing to mention this, Bem and Honorton imply that these nine studies
are reliable research.
The story of my visit to Sargent's laboratory is no secret. I
went there to try to find out why Sargent was successful with the
ganzfeld while I was not. I observed 13 sessions, of which 6 were direct
hits. I then considered whether the hits might be due to sensory
leakage, experimental error, fraud, or psi, and made predictions based
on all these hypotheses. I was satisfied that sensory leakage was not a
problem but found serious errors in the randomization procedure. This
cumbersome procedure required sets of sealed, unmarked envelopes
containing letters specifying the target selection (Sargent 1980). On
the basis of my various hypotheses I predicted specific errors in the
placement and contents of some of these envelopes and, when was able to
open all the envelopes, I found several such errors. I published the
findings and Sargent and his colleagues responded, claiming that they
were due to minor experimental error (Harley and Matthews 1987; Sargent
Whatever one's favored interpretation, it is my opinion that
these problems are serious and we should not consider Sargent's studies
a valid part of the ganzfeld database. It may be for this reason that
parapsychologists now rarely cite them as evidence for psi. So I was
disappointed to find that Bem and Honorton did not mention this at all.
They then go on to provide data from "11 new ganzfeld studies."
This will perhaps give readers the impression that the data are being
presented or the first time. In fact they were previously published, in
almost the same form, in the Journal of Parapsychology in 1990 (Honorton
et a1. 1990).
Admittedly they are impressive and deserve presentation to a
wider audience than the readers of parapsychology journals. They are the
series of experiments using the autoganzfeld - or fully automated
ganzfeld system. This was designed to meet the "stringent standards" set
by Hyman and Honorton (1986) in their joint communique-which ended the
great Ganzfeld Debate.
In this new paper Bem and Honorton claim that these "stringent
standards" have been met - a view with which I widely concur. As the
experiments are presented here, and in the previous 1990 paper, there
are no obvious methodological flaws. The results are highly significant
and the effect size is comparable to that found in previous ganzfeld
studies. There is also confirmation of findings that emerged from
earlier meta-analyses. For example, selected subjects who are artistic
and believe in psi do better than unselected subjects. They do better
when friends act as senders and dynamic targets are better than static
I think one's response to this should be optimistic. The work so
far looks promising - let's see whether the results can be replicated by
Honorton is no longer with us, but fortunately he was in
Edinburgh long enough to help set up the autoganzfeld there for others
to continue. Just a few months ago the first results were reported at
the Society for Psychical Research annual conference in Glasgow (Morris
et al. 1993).
Two pilot experiments were reported. In the first, 16 unselected
subjects, with friends as senders, tried to detect both dynamic and
static targets. Results were at chance. In a second study 32 subjects
were selected for artistic or musical ability and a positive attitude
toward psi. They were tested in pairs using dynamic targets. This time
the hit rate was over 40 percent (25 percent is expected by chance),
which is comparable to Honorton's previous results.
What can we now conclude? These were only pilot studies carried
out by students and they used a ganzfeld setup that was not quite
completed. Will these results continue when the promised refinements are
in place? Will the final setup really rule out methodological flaws and
the chance of experimenter or subject fraud? I await the next set of
results with more than bated breath.
In my opinion Bem and Honorton have overstated the strength of
the earlier ganzfeld evidence. They have completely ignored the problems
with Sargent's work and understated some of Hyman's objections. However
I agree with them that the autoganzfeld procedure appears sound and the
results are important. It is too soon for those "academic psychologists"
to change their minds about psi, but it is no bad thing that they have
been given the chance to consider it.
Bem, D. J., and C. Honorton. 1994. Does psi exist? Replicable evidence
for an anomalous process of information transfer. Psychological
Blackmore, S. J. 1987. A report of a visit to Carl Sargent's laboratory.
Journal of the Society for Psychical Research, 54:186-198.
Druckman, D., and J. A. Swets. eds. 1988. Enhancing Human Performance:
Issues, Theories and Techniques. Washington, D.C.: National Academy
Harley, T., and G. Matthews. 1987. Cheating, psi, and the appliance of
science: A reply to Blackmore. Journal of the Society for Psychical
Research 54: 199-207.
Honorton, C. 1985. Meta-analysis of psi ganzfeld research: A response to
Hyman. Journal of Parapsychology, 49: 51-86.
Honorton, C., R. E. Berger, M. P. Varvoglis, M. Quant, P. Derr, E. I.
Schechter, and D. C. Ferrari. 1990. Psi communication in the ganzfeld.
Journal of Parapsychology, 54: 99-139.
Hyman, R. 1985. The ganzfeld psi experiment: A critical appraisal.
Journal of ParapsychologY, 49: 3-49.
Hyman, R., and C. Honorton. 1986. A joint communique: The psi ganzfeld
controversy. Journal of Parapsychology, 50: 351-364.
Morris, R. L., S. Cunningham, S. McAlpine, and R. Taylor. 1993. Toward
replication and extension of autoganzfeld results. Paper presented at
the 17th International Conference of the Society for Psychical
Research, Glasgow, September 1993.
Sargent, C. L. 1980. Exploring psi in the ganzfeld. Parapsychological
Monographs, 17. New York: Parapsychological Foundation.
-------. 1987. Sceptical fairytales from Bristol. Journal of the Society
for Psychical Research, 54: 208-218.
Susan Blackmore is senior lecturer in psychology, University of the West
of England, Bristol BS16 2JP, England.