Approved For Release 2000/08/08
: CIA-RDP96-00789R003200110001-4
DARYL
J. BEM AND CHARLES HONORTON
the TV monitor after each clip was shown. The receiver was permitted
to see each clip and to change the ratings repeatedly until he or she was
satisfied. The computer then wrote these and other data from the session
into a file on a floppy disk. At that point, the sender moved to the receiv-
er’s chamber and revealed the identity of the target to both the receiver
and the experimenter. Note that the experimenter did not even know
the identity of the four-clip judging set until it was displayed to the re-
ceiver forjudging.
Randomization.
The random selection ofthe target and sequencing
ofthe judging set were controlled by a noise-based random number gen-
erator interfaced to the computer. Extensive testing confirmed that the
generator was providing a uniform distribution of values throughout
the full target range (1-160). Tests on the actual frequencies observed
during the experiments confirmed that targets were, on average, selected
uniformly from among the 4 clips within each judging set and that the
4 judging sequences used were uniformly distributed across sessions.
Additional controlfeatures.
The receiver’s and sender’s rooms were
sound-isolated, electrically shielded chambers with single-door access
that could be continuously monitored by the experimenter. There was
two-way intercom communication between the experimenter and the
receiver but only one-way communication into the sender’s room; thus,
neither the experimenter nor the receiver could monitor events inside
the sender’s room. The archival record for each session includes an au-
diotape containing the receiver’s mentation during the ganzfeld period
and
all verbal exchanges between the experimenter and the receiver
throughout the experiment.
The automated ganzfeld
protocol has been examined by
several
dozen parapsychologists and behavioral researchers from other fields,
including well-known
critics of parapsychology. Many have partici-
pated as subjects or observers. All have expressed satisfaction with the
handling of security issues and controls.
Parapsychologists have often been urged to employ magicians as con-
sultants to ensure that the experimental protocols are not vulnerable
either to inadvertent sensory leakage or to deliberate cheating. Two
“mentalists,” magicians who specialize in the simulation of psi, have
examined the autoganzfeld system and protocol. Ford Kross, a profes-
sional mentalist and officer of the mentalist’s professional organization,
the Psychic Entertainers Association, provided the following written
statement “In my professional capacity as a mentalist,
I have reviewed
Psychophysical Research Laboratories’ automated ganzfeld system and
found
it to provide excellent security against deception by subjects”
(personal communication, May,
1 989).
Daryl J. Bern has also performed as a mentalist for many years and is
a member of the Psychic Entertainers Association. As mentioned in
the author note, this article had its origins in a 1983 visit he made to
Honorton’s laboratory, where he was asked to critically examine the
research protocol from the perspective of a mentalist, a research psy-
chologist, and a subject. Needless to say, this article would not exist if he
did not concur with Ford Kross’s assessment ofthe security procedures.
Experimental Studies
Altogether, 100 men and 140 women participated as receivers in 354
sessions during the research program.
5 The participants ranged in age
from
1 7 to 74 years (M = 37.3, SD =
1 .8), with a mean formal educa-
tion of 15.6 years (SD = 2.0). Eight separate experimenters, including
Honorton, conducted the studies.
The experimental program included three pilot and eight formal
studies. Five of the formal studies used novice (first-time) participants
who served as the receiver in one session each. The remaining three
formal studies used experienced participants.
Pilot studies.
Sample sizes were not preset in the three pilot studies.
Study
1 comprised 22 sessions and was conducted during the initial
development and testing of the autoganzfeld system. Study 2 comprised
9 sessions testing a procedure in which the experimenter, rather than
the receiver, served as the judge at the end of the session. Study 3 com-
prised 35 sessions and served as practice for participants who had com-
pleted the allotted number ofsessions in the ongoing formal studies but
who wanted additional ganzfeld experience. This study also included
several demonstration sessions when TV film crews were present.
Novice studies.
Studies 101-104 were each designed to test 50 par-
ticipants who had had no prior ganzfeld experience; each participant
served as the receiver in a single ganzfeld session. Study
1 04 included
of 20 students recruited from the Juilliard School in New York City to
test an artistically gifted sample. Study 105 was initiated to accommo-
date the overflow of participants who had been recruited for Study 104,
including the 4 remaining Juilliard students. The sample size for this
study was set to 25, but only 6 sessions had been completed when the
laboratory closed. For purposes ofexposition, we divided the 56 sessions
from Studies 104 and 105 into two parts: Study 104/ 105(a) comprises
the 36 non-Juilliard participants, and Study 104/ 105(b) comprises the
20 Juilliard students.
Study 201.
This study was designed to retest the most promising
participants from the previous studies. The number of trials was set to
20, but only 7 sessions with 3 participants had been completed when
the laboratory closed.
Study 301.
This study was designed to compare static and dynamic
targets. The sample size was set to 50 sessions. Twenty-five experienced
participants each served as the receiver in 2 sessions. Unknown to the
participants, the computer control program was modified to ensure that
they would each have
1 session with a static target and
1 session with a
dynamic target.
Study 302.
This study was designed to examine a dynamic target
set that had yielded a particularly high hit rate in the previous studies.
The study involved experienced participants who had had no prior ex-
perience with this particular target set and who were unaware that only
one target set was being sampled. Each served as the receiver in a single
session. The design called for the study to continue until
15 sessions
were completed with each of the targets, but only 25 sessions had been
completed when the laboratory closed.
The
1 studies just described comprise all sessions conducted during
the 6.5 years of the program. There is no “file drawer” of unreported
sessions.
Results
Overall hit rate.
As in the earlier meta-analysis, receivers’
ratings were analyzed by tallying the proportion of hits achieved
and calculating the exact binomial probability for the observed
number of hits compared with the chance expectation of .25.
As noted earlier, 240 participants contributed 354 sessions. For
reasons discussed later, Study 302 is analyzed separately, reduc-
ing the number of sessions in the primary analysis to 329.
As Table
1 shows, there were 106 hits in the 329 sessions, a
hit rate of 32% (z = 2.89, p = .002, one-tailed), with a 95%
confidence interval from 30% to 35%. This corresponds to an
effect size (rr) of .59, with a 95% confidence interval from .53 to
.64.
Table
1 also shows that when Studies 104 and 105 are com-
bined and re-divided into Studies 104/105(a) and 104/105(b), 9
5 A recent review ofthe original computer files uncovered a duplicate
record in the autoganzfeld database. This has now been eliminated, re-
ducing by one the number of subjects and sessions. As a result, some of
the numbers presented in this article differ slightly from those in Hon-
orton et al. (1990).
: CIA-RDP96-00789R003200110001-4
Approved For Release 2000/08/08
Approved For Release 2000/08/08
: CIA-RDP96-00789R003200110001-4
ANOMALOUS INFORMATION TRANSFER
Table
Outcome by Study
Study
Study/subject description
N
subjects
N
trials
N
hits
%
hits
Effect
size 7
r
z
Pilot
.62
0.99
Pilot
.60
0.25
Pilot
.55
0.32
101
Novice
.47
-0.30
102
Novice
.63
1.60
103
Novice
.55
0.67
104/105(a)
Novice
.60
0.97
104/ 105(b)
Juilliard sample
.75
2.20
201
Experienced
.69
0.69
301
Experienced
.56
0.67
302
Experienced
54“
.78“
3.04
a
Overall
(Studies 1-301)
240
329
106
.59
2.89
Note.
All z scores are based on the exact binomial probability, with p - .25 and g - .75.
a Adjusted for response bias; the hit rate actually observed was 64%.
of the 10 studies yield positive effect sizes, with a mean effect
size (it) of .6 1 , t(9) = 4.44, p = .0008, one-tailed. This effect size
is equivalent to a four-alternative hit rate of 34%. Alternatively,
if Studies 104 and 105 are retained as separate studies, 9 of the
10 studies again yield positive effect sizes, with a mean effect
size (tr) of .62, /(9) = 3.73, p = .002, one-tailed. This effect size
is equivalent to a four-alternative hit rate of 35% and is identical
to that found across the 28 studies of the earlier meta-analysis.
Considered together, sessions with novice participants (Stud-
ies 101-105) yielded a statistically significant hit rate of 32.5%
(
p
= .009), which is not significantly different from the 31.6%
hit rate achieved by experienced participants in Studies 20 1 and
301. And, finally, each of the eight experimenters also achieved
a positive effect size, with a mean it of .60, t(7) = 3.44, p = .005,
one-tailed.
The Juilliard sample.
There are several reports in the liter-
ature of a relationship between creativity or artistic ability and
psi performance (Schmeidler, 1988). To explore this possibility
in the ganzfeld setting, 10 male and 10 female undergraduates
were recruited from the Juilliard School. Ofthese, 8 were music
students, 10 were drama students, and 2 were dance students.
Each served as the receiver in a single session in Study 104 or
105. As shown in Table
1, these students achieved a hit rate of
50% (p = .014), one of the five highest hit rates ever reported for
a single sample in a ganzfeld study. The musicians were partic-
ularly successful: 6 of the 8 (75%) successfully identified their
targets (p = .004; further details about this sample and their
ganzfeld performance were reported in Schlitz & Honorton,
1992).
Study size and effect size.
There is a significant negative cor-
relation across the 10 studies listed in Table
1 between the num-
ber of sessions included in a study and the study’s effect size (ir),
r = -.64, 1(8) = 2.36, p < .05, two-tailed. This is reminiscent
of Hyman’s discovery that the smaller studies in the original
ganzfeld database were disproportionately likely to report sta-
tistically significant results. He interpreted this finding as evi-
dence for a bias against the reporting of small studies that fail to
achieve significant results. A similar interpretation cannot be
applied to the autoganzfeld studies, however, because there are
no unreported sessions.
One reviewer of this article suggested that the negative corre-
lation might reflect a decline effect in which earlier sessions of a
study are more successful than later sessions. If there were such
an effect, then studies with fewer sessions would show larger
effect sizes because they would end before the decline could set
in. To check this possibility, we computed point-biserial corre-
lations between hits (1) or misses (0) and the session number
within each of the 10 studies. All of the correlations hovered
around zero; six were positive, four were negative, and the over-
all mean was .0 1
.
An inspection of Table
1 reveals that the negative correlation
derives primarily from the two studies with the largest effect
sizes', the 20 sessions with the Juilliard students and the 7 ses-
sions of Study 201, the study specifically designed to retest the
most promising participants from the previous studies. Accord-
ingly, it seems likely that the larger effect sizes of these two stud-
ies—and hence the significant negative correlation between the
number of sessions and the effect size—reflect genuine perfor-
mance differences between these two small, highly selected sam-
ples and other autoganzfeld participants.
Study 302.
All of the studies except Study 302 randomly
sampled from a pool of 160 static and dynamic targets. Study
302 sampled from a single, dynamic target set that had yielded
a particularly high hit rate in the previous studies. The four film
clips in this set consisted of a scene of a tidal wave from the
movie Clash ofthe Titans, a high-speed sex scene from A Clock-
work Orange, a scene of crawling snakes from a TV documen-
tary, and a scene from a Bugs Bunny cartoon.
6 As noted above, the laboratory was forced to close before three of
the formal studies could be completed. Ifwe assume that the remaining
trials in Studies 105 and 201 would have yielded only chance results,
this would reduce the overall z for the first 10 autoganzfeld studies from
2.89 to 2.76 (p = .003). Thus, inclusion of the two incomplete studies
does not pose an optional stopping problem. The third incomplete
study. Study 302, is discussed below.
*
Approved For Release 2000/08/08
: CIA-RDP96-00789R003200110001-4
Approved For Release 2000/08/08
: CIA-RDP96-00789R003200110001-4
DARYL
J. BEM AND CHARLES HONORTON
The experimental design called for this study to continue un-
til each of the clips had served as the target
1 5 times. Unfortu-
nately, the premature termination of this study at 25 sessions
left an imbalance in the frequency with which each clip had
served as the target. This means that the high hit rate observed
(64%) could well be inflated by response biases.
As an illustration, water imagery is frequently reported by
receivers in ganzfeld sessions, whereas sexual imagery is rarely
reported. (Some participants probably are reluctant both to re-
port sexual imagery and to give the highest rating to the sex-
related clip.) If a video clip containing popular imagery (such as
water) happens to appear as a target more frequently than a
clip containing unpopular imagery (such as sex), a high hit rate
might simply reflect the coincidence of those frequencies of oc-
currence with participants’ response biases. And, as the second
column of Table 2 reveals, the tidal wave clip did in fact appear
more frequently as the target than did the sex clip. More gener-
ally, the second and third columns of Table 2 show that the fre-
quency with which each
film
clip was ranked
first
closely
matches the frequency with which each appeared as the target.
One can adjust for this problem by using the observed fre-
quencies in these two columns to compute the hit rate expected
if there were no psi effect. In particular, one can multiply each
proportion in the second column by the corresponding propor-
tion in the third column—yielding the joint probability that the
clip was the target and that it was ranked first—and then sum
across the four clips. As shown in the fourth column of Table 2,
this computation yields an overall expected hit rate of 34.08%.
When the observed hit rate of 64% is compared with this base-
line, the effect size (h) is .6 1
. As shown in Table
, this is equiv-
alent to a four-alternative hit rate of 54%, or a n value of .78,
and is statistically significant (z = 3.04, p = .00
1 2).
The psi effect can be seen even more clearly in the remaining
columns ofTable 2, which control for the differential popularity
of the imagery in the clips by displaying how frequently each
was ranked first when it was the target and how frequently it was
ranked first when it was one of the control clips (decoys). As can
be seen, each ofthe four clips was selected as the target relatively
more frequently when it was the target than when it was a decoy,
a difference that
is significant for three of the four clips. On
average, a clip was identified as the target 58% of the time when
it was the target and only 14% of the time when it was a decoy.
Dynamic versus static targets.
The success of Study ioz
raises the question of whether dynamic targets arc, in general,
more effective than static targets. This possibility was also sug-
gested by the earlier meta-analysis, which revealed that studies
using multiple-image targets (View Master stereoscopic slide
reels) obtained significantly higher hit rates than did studies us-
ing single-image targets. By adding motion and sound, the video
clips might be thought ofas high-tech versions of the View Mas-
ter reels.
The
10 autoganzfeld studies that randomly sampled from
both dynamic and static target pools yielded 164 sessions with
dynamic targets and 165 sessions with
static targets. As pre-
dicted,
sessions
using dynamic
targets
yielded
significantly
more hits than did sessions using static targets (37% vs. 27%,
Fisher’s exact p < .04).
Sender-receiver pairing.
The earlier meta-analysis
i evealed
that studies in which participants were free to bring in friends
Approved For Release 2000/08/08
: CIA-RDP96-00789R003200110001-4
Approved For Release 2000/08/08
: CIA-RDP96-00789R003200110001-4
ANOMALOUS INFORMATION TRANSFER
to serve as senders produced significantly higher hit rates than
studies that used only laboratory-assigned senders. As noted,
however, there is no record of how many of the participants in
the former studies actually did bring in friends. Whatever the
case, sender-receiver pairing was not a significant correlate of
psi performance in the autoganzfeld studies: The 197 sessions
in which the sender and receiver were friends did not yield a
significantly higher proportion of hits than did the 132 sessions
in which they were not (35% vs. 29%; Fisher’s exact p = .28).
Correlations between receiver characteristics and psi perfor-
mance.
Most of the autoganzfeld participants were strong be-
lievers in psi: On a 7-point scale ranging from strong disbeliefin
psi ( 1 ) to strong beliefin psi (7), the mean was 6.2 (SD =
1 .03);
only 2 participants rated their belief in psi below the midpoint
of the scale. In addition, 88% of the participants reported per-
sonal experiences suggestive of psi, and 80% had some training
in meditation or other techniques involving internal focus of
attention.
All ofthese appear to be important variables. The correlation
between belief in psi and psi performance is one of the most
consistent findings in the parapsychological literature (Palmer,
1978). And, within the autoganzfeld studies, successful perfor-
mance of novice (first-time) participants was significantly pre-
dicted by reported personal psi experiences, involvement with
meditation or other mental disciplines, and high scores on the
Feeling and Perception factors of the Myers-Briggs Type Inven-
tory (Honorton, 1992; Honorton & Schechter, 1987; Myers &
McCaulley, 1985). This recipe for success has now been inde-
pendently replicated in another laboratory (Broughton, Kan-
thamani, & Khilji, 1990).
The personality trait of extraversion
is also associated with
better
psi performance. A meta-analysis of 60 independent
studies with nearly 3,000 subjects revealed a small but reliable
positive correlation between extraversion and psi performance,
especially in studies that used free-response methods ofthe kind
used in the ganzfeld experiments (Honorton, Ferrari, & Bern,
1992). Across 14 free-response studies conducted by four inde-
pendent investigators, the correlation for 6 1 2 subjects was .20
(z = 4.82, p =
1.5 X 10“6
). This correlation was replicated in
the autoganzfeld
studies,
in which extraversion scores were
available for 2
8 of the 240 subjects, r =
. 1 8 , t(2 1 6) = 2.67, p =
.004, one-tailed.
Finally, there
is the strong psi performance of the Juilliard
students, discussed earlier, which is consistent with other studies
in the parapsychological literature suggesting a relationship be-
tween successful psi performance and creativity or artistic abil-
ity.
Discussion
Earlier in this article, we quoted from the abstract of the Hy-
man-Honorton (1986) communique: “We agree that the final
verdict awaits the outcome of future experiments conducted by
a broader range of investigators and according to more stringent
standards” (p. 351). We believe that the “stringent standards”
requirement has been met by the autoganzfeld studies. The re-
sults are statistically significant and consistent with those in the
earlier database. The mean effect size
is quite respectable in
comparison with other controversial research areas of human
performance (Harris & Rosenthal, 1988a). And there are reli-
able relationships between successful psi performance and con-
ceptually relevant experimental and subject variables, relation-
ships that also replicate previous findings. Hyman (1991) has
also commented on the autoganzfeld studies: “Honorton’s ex-
periments have produced intriguing results. If .
.
. independent
laboratories can produce similar results with the same relation-
ships and with the same attention to rigorous methodology, then
parapsychology may indeed have
finally captured
its elusive
quarry” (p. 392).
Issues of Replication
As Hyman’s comment implies, the autoganzfeld studies by
themselves cannot satisfy the requirement that replications be
conducted by a “broader range of investigators.” Accordingly,
we hope the findings reported here will be sufficiently provoca-
tive to prompt others to try replicating the psi ganzfeld effect.
We believe that
it is essential, however, that future studies
comply with the methodological, statistical, and reporting stan-
dards set forth in the joint communique and achieved by the
autoganzfeld studies. It is not necessary for studies to be as au-
tomated or as heavily instrumented as the autoganzfeld studies
to satisfy the methodological guidelines, but they are still likely
to be labor intensive and potentially expensive.
Statistical Power and Replication
Would-be replicators also need to be reminded of the power
requirements for replicating small effects. Although many aca-
demic psychologists do not believe in psi, many apparently do
believe in miracles when
it comes to replication. Tversky and
Kahneman (1971) posed the following problem to their col-
leagues at meetings ofthe Mathematical Psychology Group and
the American Psychological Association:
Suppose you have run an experiment on 20 subjects and have ob-
tained a significant result which confirms your theory (z = 2.23,
p < .05, two-tailed). You now have cause to run an additional group
of 10 subjects. What do you think the probability is that the results
will be significant, by a one-tailed test, separately for this group? (p.
105)
The median estimate was .85, with 9 of 10 respondents provid-
ing an estimate greater than .60. The correct answer is approxi-
mately .48.
As Rosenthal ( 1 990) has warned: “Given the levels of statisti-
cal power at which we normally operate, we have no right to
expect the proportion of significant results that we typically do
expect, even if in nature there is a very real and very important
effect” (p.
16). In this regard, it is again instructive to consider
the medical study that revealed a highly significant effect of as-
pirin on the incidence of heart attacks. The study monitored
more than 22,000 subjects. Had the investigators monitored
3,000 subjects, they would have had less than an even chance of
7 As the closing of the autoganzfeld laboratory exemplifies, it is also
difficult to obtain funding for psi research. The traditional, peer-refer-
eed sources of funding familiar to psychologists have almost never
funded proposals for psi research. The widespread skepticism of psy-
chologists toward psi is almost certainly a contributing factor.
Approved For Release 2000/08/08
: CIA-RDP96-00789R003200110001-4