Approved For Release 2000/08/07
: CIA-RDP96-00788R001 300350001-0
£>03
A?
Final Report
SENSING OF REMOTE EM SOURCES
(PHYSIOLOGICAL CORRELATES)
By:
BUSSELL TARG
EDWIN MAY
HAROLD PUTHOFF
SRI
International, Menlo Park ,
California
DAVID GALIN
ROBERT ORNSTEIN
Langley Porter Neuropsychiatric
Institute, San
Francisco,
California
Prepared
for:
NAVAL ELECTRONICS SYSTEMS COMMAND
WASHINGTON,
D.C.
20360
Attention;
MR, JAMES FOOTE
ELEX 03X
CONTRACT N00039-76-C-0077
333
Ravenswood
Avenue
Menlo
Park,
California
94025
U.S.A.
(415)
326-6200
Cable:
STANRES,
Menlo
Park
TWX;
910-373-1246
Approved For Release 2000/08/07
: CIA-RDP96-00788R001 300350001-0
Approved For Release 2000/08/07
: CIA-RDP96-00788R001 300350001-0
UNCLASSIFIED
SECURITY CLASSIFICATION OF THIS PAG E (When Data
Entered)
"
READ INSTRUCTIONS
REPORT DOCUMENTATION PAGE
before^ completing form
2. GOVT ACCESSION NO.
3. RECIPIENT'S CATALOG NUMBER
1. REPORT NUMBER
4. TITLE
(and
Subtitle)
SENSING OF REMOTE EM SOURCES
(PHYSIOLOGICAL
CORRELATES)
7. AUTHOR(s)
Russell Targ
Edwin May
Harold Puthoff
David Gal in
Robert Ornstein
9. PERFORMING ORGANIZATION NAME AND ADDRESS
SRI International
333 Ravenswood Avenue
Menl o Park,
California
94025
11. CONTROLLING OFFICE NAME AND ADDRESS
ELEX 03X
Naval Electronics
Systems
Command
Washington,
D.C.
20360
14. MONITORING AGENCY NAME
8. ADDRESS
(if
dltf. from Controlling Office)
16.
DISTRIBUTION STATEMENT
(of this
report)
5. TYPE OF REPORT & PERIOD COVERED
Final Report
Covering the period November
1975
to October
1976
6. PERFORMING ORG. REPORT NUMBER
SRI Project 4540
8. CONTRACT OR GRANT NUMBER(s)
Contract N00039-76-C-0077
10. PROGRAM ELEMENT, PROJECT, TASK
AREA & WORK UNIT NUMBERS
12. REPORT DATE
13. NO. OF
April
1978
15. SECURITY CLASS,
(of
this
report)
UNCLASSIFIED
15a. DECLASSIFICATION /DOWNGRADING
SCHEDULE
17.
DISTRIBUTION STATEMENT
(of the abstract entered
In Block
20,
if
different from
report)
18. SUPPLEMENTARY NOTES
19. KEY WORDS (Continue on
reverse
side
if necessary and
identify by block number)
EEQ
Elecirophysiology
Electroencephlograph
Psychoenergetics
Brainwaves
Subliminal perception
20. ABSTRACT (Continue on
reverse side
if necessary and
identify by
block number)
We have investigated
the ability of certain individuals
to perceive remote
(faint)
stimuli at
a noncognitive level
of awareness.
To investigate
this we
have
looked
for systematic changes
in a subject's brainwave
(EEG)
production
occurring at
the
same time as
light flashes are generated
on a random sche u
e
in
a remote. laboratory.
We have
found in this
investigation that statistically
significant correlations
do appear
to exist between the
times
of light
flashes
and the times
of brainwave alterations.
However,
we consider
these data
to be
^
FORM
UNCLASSIFIED
'
ip
N
. ”
,s OBSOLETE
SECURITY CLASSIFICATION OF THIS PAGE (When Deta Entered)
A$p%vec^ l^or Reiease 2000/08/07
: CIA-RDP96-00788R001 300350001-0
1473
Approved For Release 2000/08/07
: CIA-RDP96-00788R001 300350001-0
CONTENTS
LIST OF ILLUSTRATIONS
v
LIST OF TABLES
vi
PART ONE:
SRI ANALYSIS
I
INTRODUCTION AND SUMMARY
II
PILOT STUDY AT SRI
III
TECHNICAL APPROACH
IV
DISCUSSION
n
PART TWO:
LANGLEY PORTER ANALYSIS
I
INTRODUCTION
i6
II
REANALYSIS OF PREVIOUS DATA
III
FIRST EXPERIMENT AT LANGLEY PORTER:
ATTEMPTED REPLICATION
OF SRI STUDY
IV
SECOND EXPERIMENT AT LANGLEY PORTER:
ATTEMPTED
REFINEMENT
V
DISCUSSION
APPENDIX:
OPTICAL ISOLATION EXPERIMENTS AT LANGLEY PORTER ....
REFERENCES
iv
Approved For Release 2000/08/07
: CIA-RDP96-00788R001 300350001-0
Approved For Release 2000/08/07
: CIA-RDP96-00788R001 300350001-0
ILLUSTRATIONS
PART ONE
Typical Power Spectrum Averaged
Over Twenty 8-s
Epoch
for One Subject
Schematic of the Remote- Sensing EEG Experiment
APPENDIX
A-l
Floor Plan and Apparatus
for Light-Leakage
Measurements
Approved For Release 2000/08/07
: CIA-RDP96-00788R001 300350001-0
Approved For Release 2000/08/07
: CIA-RDP96-00788R001 300350001-0
TABLES
PART ONE
Summary of Results of the Replication Experiments
Showing Power Means and
Statistical Results
for the
Various Experimental Conditions ....
PART TWO
Reanalysis of Dr.
Rebert's
SRI
Tapes Played Through
the Langley Porter EEG Alpha Analyzer
First Experiment at Langley Porter:
Means of Summed
EEG Alpha in Relative Power Units
Second Experiment at Langley Porter:
All
Trials,
Sender vs No Sender
Second Experiment at Langley Porter:
Guess
Trials
Only,
Sender vs No Sender
Second Experiment at Langley Porter:
Pass
Trial Means
...
Second Experiment at Langley Porter:
Correct Guess
Trial Means
vi
Approved For Release 2000/08/07
: CIA-RDP96-00788R001 300350001-0
Approved For Release 2000/08/07
: CIA-RDP96-00788R001 300350001-0
PART ONE:
SRI ANALYSIS
Russell Targ
Edwin May
Harold Puthoff
SRI International
Menlo Park,
California
Approved For Release 2000/08/07
: CIA-RDP96-00788R001 300350001-0
Approved For Release 2000/08/07
: CIA-RDP96-00788R001 300350001-0
I
INTRODUCTION AND SUMMARY
A.
Introduction
The objective of the program reported here was
to investigate
the characteristics
of,
and,
if possible,
determine
the mechanisms
responsible
for,
the coupling of remote electromagnetic stimuli
to human
detection modalities,
utilizing physiological response
(specifically,
EEG)
as
an indication of such registration*
In
a number
of laboratories
evidence has been obtained
indi-
cating
the existence of an as-yet-unidentified channel wherein informa-
tion
is
coupled
from remote electromagnetic stimuli to the human nervous
system,
as
indicated by physiological responses.
This
coupling can be
measured,
even though overt
subject responses
such
as verbalizations
or
pressing of
a key provide no evidence
for
such information transfer.
i *
Physiological measures have included plethysmographic response
and EEG
activity . 2
' 3
Kamiya,
Lindsley,
Pribram,
Silverman,
Walter,
and
others
have suggested
that
a whole range of EEG responses
such as
evoked
poten-
tials
(EPs),
spontaneous
EEG,
and
the contingent negative variation
(CNV)
might
be sensitive
indicators
of the detection of remote
stimuli not
mediated by usual
sensory processes.
A pilot study was
therefore undertaken at
SRI
to determine
whether EEG activity could
be used
as
a reliable indicator of informa-
tion transmission between an
isolated subject and
a remote stimulus.
Following earlier work of others,
we assumed
that perception could
be
indicated by such
a measure even in
the absence of verbal
or
other overt
indicators.
To aid
in selecting
a
stimulus,
we noted
that
Silverman and
Buchsbaum attempted,
without
success,
to detect EP changes
in a
subject
in response
to
a single stroboscopic
flash stimulus per
trial observed
by another
subject . 6
Kamiya suggested that because of the unknown
temporal characteristic
of the information channel,
it might be more
References
are
listed
at
the
end
of this report.
Approved For Release 2000/08/07
: CIA-RDP96-00788R001 300350001-0
Approved For Release 2000/08/07
: CIA-RDP96-00788R001 300350001-0
appropriate
to use repetitive bursts
of light
to increase the probability
of detecting information transfer . 6
Therefore,
in our study we chose
to
*
7 -9
use repetitive
light bursts
as
stimuli.
B.
Summary
In Section
II we describe
the pilot study conducted at
SRI,
which
led
to
the present
investigation.
It was
in this
study that we
obtained
our
first
indication that remote light- flash stimuli could
cause systematic
changes
in the observed EEG production of an individual
shielded
against direct perception of the
light.
Section
III presents
the technical approach employed
in the
most recent
investigations.
This includes
a description of
the battery-
operated
strobe
light equipment,
shielding precautions,
experimental
protocol,
and finally data
analysis.
Section IV presents
a detailed discussion of
the results
from
all phases
of the
study.
Part Two of this report
is
the technical evaluation prepared
for
us by our independent consultants
at Langley Porter Neuropsychiatric
Institute.
In their report they analyze the present
investigation from
the point
of view of practicing perceptual psychologists.
In the Appendix
to
this report we describe
the optical measure-
ments made to determine the extent of possible light
leakage
from the
stimulus room to
the subject room.
II
PILOT STUDY AT SRI
In the design of the study it was assumed
that
the application of
remote stimuli might result
in responses
similar
to those obtained
under conditions
of direct
stimulation.
For example,
when normal
sub-
jects 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 . 10
We hypothesized
that
if
we stimulated one subject
in this manner
(a putative
sender),
the EEG
of another
subject
in a remote room with no
flash present
(a receiver)
Approved For Release 2000/08/07
: CIA-RDP96-00788R001 300350001-0
Approved For Release 2000/08/07
: CIA-RDP96-00788R001 300350001-0
might show changes
in alpha
(8 to
13 Hz)
activity,
and possibly EEG
driving similar
to
that of the
sender,
either by means
of coupling to
the sender's
EEG,
or by coupling directly to the stimulus.
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
per-
ceived
that
event,
consciously
or unconsciously,
it might
be evident
from changes
in his EEG output.
The receiver was
seated
in a visually
opaque,
acoustically and electrically shielded double-walled steel room
located approximately
7 m from the
sender's
room.
We initially worked with
four
female and two male volunteer
sub-
jects.
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 with each subject
in this
selection pro-
cedure,
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
s duration.
The receiver's
EEG
activity from the occipital region
(Oz),
referenced
to
linked mastoids,
was amplified with a Grass 5P-1 preamplifier and associated driver ampli-
fier with
a bandpass
of
to
120
Hz.
The EEG data were recorded
on
magnetic
tape with an Ampex SP300 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
of flashes
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
flashes
per
second
(fps)
and
12 trials
of
flashes
at
fps,
all randomly inter-
mixed,
determined
by entries
from
a table of random numbers.
Each of
the trials consisted
of an 11-s EEG epoch.
The last 4
s
of the epoch
were selected
for analysis
to minimize the desynchronizing action of the
warning cue.
This 4-s
segment was
subjected
to Fourier analysis
on
a
LINC
8 computer.
Approved For Release 2000/08/07
: CIA-RDP96-00788R001 300350001-0
Approved For Release 2000/08/07
: CIA-RDP96-00788R001 300350001-0
Spectrum analyses
gave no evidence of EEG driving in any receiver,
although in control runs
the receivers did exhibit driving when physi-
cally stimulated with
the flashes.
But
of the six subjects
studied
initially,
one subject showed
a consistent alpha blocking effect.
We
therefore undertook further study with this
subject.
We note
that
of
our
six subjects,
this
one had
the most monochromatic EEG spectrum.
Figure
shows
a typical occipital EEG spectrum of
this
subject.
o
FREQUENCY — Hz
FIGURE
TYPICAL POWER SPECTRUM AVERAGED OVER TWENTY
8-SECOND EPOCHS FOR ONE SUBJECT
Data
from seven
sets
of
trials each were collected
from this
subject
on three separate days.
This comprised 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.
The
final analysis
showed that power
values were
less
in the 16-fps
case than in the 0-fps case
(no
light)
in
all seven sets of peak power measurements and in six out
of seven
average-power measurements.
Siegel's two-tailed
t approximation to the nonparametric randomi-
zation test11
was
applied
to
the data from all
sets,
which included two
Approved For Release 2000/08/07
: CIA-RDP96-00788R001 300350001-0
Approved For Release 2000/08/07
: CIA-RDP96-00788R001 300350001-0
sessions
in which the sender was removed.
Average power during trials
associated with the occurrence of
fps was
significantly less
than
when there were no flashes
(t =
2.09,
df =
118,
p < 0.04).
The second
measure,
peak power,
was also significantly less
in the 16-fps conditions
than in the null condition
(t =
2.16,
df =
118,
p < 0.03).
The response
in the
6-fps condition was
in the same direction as
that associated with
fps,
but
the effect was not statistically significant.
As part
of the experimental
protocol
for
each trial,
the subject
was asked to indicate conscious assessment
as
to which stimulus was
generated.
The guess was registered by
the
subject via one-way tele-
graphic 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.
Several control procedures were undertaken to determine if these
results were produced by system artifacts
or by subtle cueing of the
subject.
Low-level recordings were made from saline of 12-kilohm
resistance
in place of the subject,
with and without
the introduction
of
10-Hz,
50-|j,V signals
from a battery-operated
generator.
The standard
experimental protocol was adhered
to and
spectral analysis
of the results
were carried
out.
There was no evidence
in the spectra associated with
the flash frequencies,
and
the
10-Hz
signal was not
perturbed.
In another control procedure
a
five-foot pair
of leads was
draped
across
the subject's
chair
(subject absent).
The leads were connected
to one
input
of
a C.A.T.
400C "averager."
Two-second
sweeps,
triggered
at onset
of the
tone,
were taken once every
s
for approximately two
hours,
for about 550 samples.
No difference
in noise
level between the
fore-period and the onset of flicker was
observed.
Ill
TECHNICAL APPROACH
A.
Replication Studies
at Langley Porter
The main effort of the program was directed
toward replication,
by an independent
laboratory,
of the original
SRI study of EEG response
Approved For Release 2000/08/07
: CIA-RDP96-00788R001 300350001-0
Approved For Release 2000/08/07
: CIA-RDP96-00788R001 300350001-0
to remote strobe-light
stimuli.
Arrangements
for replication were made
with the Langley Porter Neuropsychiatric
Institute,
University of
California Medical
Center,
San Francisco.
Dr.
David Galin and
Dr.
Robert Ornstein were our principal consultants.
As
a special precaution against the possibility of system
artifacts
in the form of electromagnetic pickup
from the strobe- light
discharge
or associated electronic equipment
(e.g.,
through the power
lines),
SRI developed an entirely-battery-operated package
for use as
a
stimulus generator
for the EEG experimentation.
It consists of
a
battery-driven incandescent
lamp,
whose CW output
passes
through a
mechanical
chopper continuously driven by
a battery-powered motor
as
shown in Figure
2.
A 10-Hz
timing generator
(computer
triggered)
con-
trols
the generation of a 1-kHz warning tone
s before onset of the
experimental
period,
and also drives
a locking circuit
that determines
the presence
or absence of the
10-s
light
stimulus,
again all battery
operated.
Thus everything on the left of the diagram of Figure
is
battery operated and therefore independent of the power-line
system.
Further,
the arc-discharge strobe lamp was replaced by an incandescent
lamp
to eliminate the possibility of direct subliminal pickup of audio
or electrical signals
from possible transients associated with the arc
discharge
or associated electronics.
Finally,
the possibility of artifact due
to light-leakage
between the
lamp
(stimulus)
and
subject
(receiver) was investigated
by
the use of a photomultiplier
in conjunction with
a phase-sensitive
detection system.
The results,
presented in detail
in the Appendix,
indicated no light
leakage between the rooms
in question
to the
limit
of
our measurement capability
(125 dB attenuation).
1.
Description of the EEG Processor
A hardware single- channel power spectrum analyzer was
constructed
from a commercial bandpass
filter with corner
frequencies
of 9.0 and
12.0
Hz,
and a roll-off 48 dB down at 8.0 and
13.0 Hz.
Analog
multipliers convert
the filter output
to a signal proportional
to in-band
Approved For Release 2000/08/07
: CIA-RDP96-00788R001 300350001-0
Approved For Release 2000/08/07
: CIA-RDP96-00788R001 300350001-0
power.
To confirm that
this
system
is
equivalent
to the standard
FFT
analysis used
in the pilot
study,
the analog data on the
entire pilot
study were reanalyzed,
and
the result was
found
to be consistent with
the earlier
analysis.
2.
Experimental Protocol
Each experimental
session consisted
of 40
trials,
20 each
for
the
0-fps
(no
light)
and
the
16-fps
case
of
the remote
light
stimulus.
A trial
is defined
as
a warning
tone
followed
by a
10-s
period consisting
of
a
2-s wait,
and
two 4-s data-collection periods.
The
trial
rate was
one
trial every
±
s.
The
trial
sequence was randomized subject
to
the
following conditions:
(1)
in each group of
10 trials
there were
equal numbers
of each condition,
and
(2)
no more than three
in
a row of
a
single type were allowed.
Seven 40-trial
sequences were made according
to
this prescription and recorded
separately on audio
tape.
During
the
session,
trials were generated
from one of these
tapes
chosen blind
to
the experimenters
so
that
the
sequence was unknown
to
them.
As
in
standard
EEG protocol,
and
in accordance with preestablished criteria,
certain trials were deleted after
the session
for
three
reasons
only:
artifact,
logic
circuit
failure,
or
abnormal
EEG power.
If
a
trial was
rejected,
a trial
of the opposite
stimulus condition was rejected
at
random from
the particular
set
of
10 trials
in question.
If more
than
10 trials
of
a given type were rejected
from
a
session,
the
entire
session was
deleted.
(This occurred
twice in each of the two experiments
of the
study,
described below.
)
Six channels
of EEG and
one
logic
channel
taken
from the
sequence
tape were recorded
on
a multiplexed
FM analog tape recorder.
The
logic
on the
tape differentiated
the
trials
as
to
flashing and
nonflashing conditions.
In pretesting
the
equipment,
we ran
the experiment using
unselected
subjects
such
as
laboratory personnel,
in order
to
test
the
adequacy of
the experiment
and
to determine whether there were any
correlated electronic
or mechanical discharges
from the apparatus.
In
%
Approved For Release 2000/08/07
: CIA-RDP96-00788R001 300350001-0
Approved For Release 2000/08/07
: CIA-RDP96-00788R001 300350001-0
20 sessions
of data acquisition,
of 40 each
(800 trials)
there were no
significant differences between the null and 16-Hz conditions.
The
absence of differences can also be taken as
a demonstration of the non-
responsiveness
of the unselected subjects.
B.
Results
Using the above protocol,
two experiments were conducted
in
the course of the
study,
the first consisting of twelve
sessions,
the
second,
fourteen.
For half of the twelve sessions
in the initial
experi-
ment,
the
subject was asked
to press
a button when
she
felt
the
light
was
flashing.
For
the
six sessions
(105
trials
each
for
the
0-
and
16-fps
conditions) when she was not asked
to overtly indicate her
feelings
about
the
light,
there was
a
slight decrease of
in-band
EEG power measured
over
the
left occipital region of the brain.
For
the six sessions
(107
trials each
for
the
0-
and
16-fps conditions) when she was asked
to
respond
overtly,
there was
a significant decrease of
in-band EEG power
(p ^
0.037,
using an
F ratio
test derived from a two-way analysis
of
variance).
In considering the experiment
as consisting of the combined
212 trials
in each stimulus
condition regardless of the overt response
contingency,
we
find
a statistically significant decrease
in in-band
EEG power
(p < 0.011,
using
F ratio test
as above).
During the second experiment
of fourteen sessions,
three months
later,
a different contingency was added
to determine
if
a "sender" was
necessary to produce
the effect we had observed
earlier.
For
a given
session,
a random procedure
(with equal trials) was used
to determine
if
a person
(called
the "sender" person) would be
looking
at
the photo-
simulator.
There was no one present with the photo- stimulator
otherwise.
For
the
"non-sender"
sessions
(121
trials each
for
the
0- and
16-fps
conditions) we
find a statistically significant increase of in-band EEG
power measured over
the mid-occipital region of the brain
(p <
0. 039
using an F ratio test as above).
During
the
"sender"
sessions
(123
trials
in each stimulus condition)
there was
a
slight
increase of
in-
band EEG power.
When all 244 trials were analyzed,
regardless
of
"sender" condition,
there was
a statistically significant
increase
of
Approved For Release 2000/08/07
: CIA-RDP96-00788R001 300350001-0
Approved For Release 2000/08/07
: CIA-RDP96-00788R001 300350001-0
in-band EEG power
(p < 0.008 using an
F ratio test
as above),
and
there
was no significant difference
found between "sender" and "no-sender"
conditions.
For both experiments,
we considered in-band EEG power
for
the
0-to-4-s and 4-to-8-s
time periods
independently,
to determine if the
effects were time dependent.
Although some of
these
isolated subinter-
vals were statistically significant,
no systematic relationship
emerged.
Thus
the effect appears
to be cumulative over the
s.
The 0-to-8-s
results are summarized
in Table
1.
IV
DISCUSSION
Although our pilot experiment and
the two replication studies all
showed significant changes
in EEG production correlated with the presence
or absence of
a remote light
stimulus,
the sign of the systematic change
in power
in the third study was opposite
to that
of the
first
two.
We
therefore undertook a detailed
frequency analysis
of the EEG data
tapes
from the
last
two experiments,
since
the pilot experiment had already
been subjected
to
fast- Fourier- transform
(FFT)
analysis.
We conjectured
that
the observed power change in these experiments might be the result
of a very small
frequency shift,
which could become translated
into
a
large amplitude change due
to discriminator action of the alpha-band
filter.
In a chapter
on alpha blocking,
Kooi,
in his
Fundamentals
of
Electroencephalography
says,
for
example,
"...attentiveness
is associated
with
a reduction in amplitude and an increase
in average frequency of
spontaneous
cerebral potentials
The center
frequency
of the alpha
rhythm may be
influenced by the type of ongoing mental activity.
Shifts
in frequency may be highly consistent
as
two different
tasks are
per-
formed alternately."
As compared with the first experiment
in which the
average peak EEG power
fell midband,
the
FFT analysis
for
the second
experiment
showed that
the average peak EEG power occurred most
often
near
8 Hz,
and
thus
fell slightly below the hardware summing window
(±3 dB at 8.7-12.4 Hz),
enhancing a possible discriminator effect.
The
FFT analysis
further
showed
that
there was an overall increase in
fre-
quency of peak power but
the shift was
statistically nonsignificant.
Approved For Release 2000/08/07
: CIA-RDP96-00788R001 300350001-0
Approved For Release 2000/08/07
: CIA-RDP96-00788R001 300350001-0
rO
&
CO
§
w
Combined
810
852
7.03
1;
460
0.0083
HM
M
<U
CO
4J
x)
d
CO
s
*
d
d
o
vO
<}
CO
CM
CO
<L>
<D
*H
O
CO
CM
o
§
CO
CO
CO
«
•
•H
CO
• r O
*h
a
a
rH
<L)
CL.
X
O
CO
is
w
CO
m
a
0)
o
o
1^-
CM
XJ
*H
m
rH
CO
o
d
w
o
CM
0\
0)
CO
•
•
co
a)
o
•
r. O
CO
rH
X)
0)
o
rH
d
CM
rH
r-.
o
rH
co
o
rO
CO
»
•
B
kO
• A o
o
rH
o
M
d
4J
•H
co
CJ
co
d
CO
a)
CO
O
o
CT\
<fr
§
0)
'H
o
<r
CM
rH
rH
CO
r-.
vO
•
•
!
O
CO
CM
. A o
a)
<U
rH
d*
d
co
X
w
CO
d
d
CM
•rt
O
CO
o>
O
CO
CO
*rl
in
co
CM
o
CO
co
cr>
•
*
CD
CO
*4*
» r o
d
<1)
rH
O
CO
rd
CO
d
r—
MH
CO
rri
U
Cy
rH
OH
_d
4H
o
MH
•H
XJ
•rH
U
4->
rH
*d
d
• A
u
rH
VI
o
rl
HH
$3
pH
a.
Approved For Release 2000/08/07
: CIA-RDP96-00788R001 300350001-0
Approved For Release 2000/08/07
: CIA-RDP96-00788R001 300350001-0
This
slight
shift
of 0.11 Hz could possibly account
for
the observed
power increase due
to the highly nonlinear discriminator
effects.
In
examining other portions of the spectrum
for further
effects,
we
found
that
systematic amplitude changes are highly dependent
on the location
in the frequency spectrum from which
the power
sum is
taken.
This
is
to
be expected,
since almost all EEG phenomena are known
to be strongly
frequency dependent.
In the
pilot study the
frequency region for analysis was centered
about
the subject* s dominant
EEG output
frequency,
with bandpass
deter-
mined
by the
full-width ten-percent
power points.
In the
two replication
studies we used hardware filters
in this
same
frequency.
FFT analysis
showed clearly that
if other
filter bands had been chosen,
significant
correlations would not have been
found
in some cases.
Thus,
although
our
filter selection was made before
the collection of any data,
other
experimenters might have reasonably chosen other criteria
for
frequency
selection.
Therefore,
although we have
found statistically significant
evidence
for
EEG correlates
to remote
light
flash stimuli
in all
three
experiments,
we consider
these data
to be only suggestive,
with
a defini-
tive result requiring further
experimentation.
In particular,
further
analysis
techniques would have
to be developed before any putative
EEG
effect could be considered
as
part
of an information transmission/
processing channel.
We wish
to acknowledge
the valuable contributions made
to
this
project by SRI consultant Mr.
David
B.
Hurt,
who designed
and constructed
the battery powered
light stimulator and
logic elements used
in the
latter
two phases
of
the program.
Approved For Release 2000/08/07
: CIA-RDP96-00788R001 300350001-0
Approved For Release 2000/08/07
: CIA-RDP96-00788R001 300350001-0
PART TWO:
LANGLEY PORTER ANALYSIS
Approved For Release 2000/08/07
: CIA-RDP96-00788R001 300350001-0
Approved For Release 2000/08/07
: CIA-RDP96-00788R001 300350001-0
Final Report
on:
EEG STUDIES
OF RESPONSES TO REMOTE STIMULATION
SRI International Subcontract
No.
14157
SRI Consultants
David Galin,
M.D.
Robert
Ornstein,
Ph.D.
Langley Porter Institute
University of California Medical
Center
San Francisco,
California
94143
Approved For Release 2000/08/07
: CIA-RDP96-00788R001 300350001-0
Approved For Release 2000/08/07
: CIA-RDP96-00788R001 300350001-0
I
INTRODUCTION
The study of perception of information despite shielding of all
known sensory channels would be greatly aided
if a paradigm could be
devised
that used
a physiological response as the major dependent
variable.
Such
a paradigm would have
the advantage of not requiring
verbal report
or even requiring the subject's awareness
of the perception.
Effects of remote stimulation might be
too weak to enter
a subject
s
awareness but nevertheless
be detectable as
a change in some physiologi-
cal
index,
such as the EEG.
This
is
the case with conventional
sub-
liminal sensory stimulation and scalp evoked potentials.
Filtering responses
to remote perception through conscious aware-
ness must add variability to such phenomena.
Removing this variability
might allow the study of remote perception in a wider
sample of subjects,
because weaker effects may be widespread
in unselected
subjects,
while
only unusual
or "psychic" subjects may be sufficiently sensitive
for
the remote stimulation to enter awareness.
Therefore
a demonstration
of a reliable EEG effect would have far-reaching implications.
A paradigm that might measure EEG response
to remote stimulation
was devised by Drs.
C.
Rebert
and
A.
Turner
in cooperation with
Dr.
H.
Puthoff and
R.
Targ of Stanford Research
Institute.
After screening
six potential
subjects,
they identified one who seemed
to produce reli-
able results
and
showed
a highly monochromatic
occipital
EEG spectrum.
When normal
subjects are stimulated with a flashing
light,
their
EEG normally shows
a decrease in the power of the alpha rhythm and
a
driving at
the
frequency of the
flashes
(Hill and Parr,
1963).
The
SRI
group hypothesized
that
if they 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
a decrease
in alpha activity,
and
possibly EEG driving similar
to
that
of
the sender.
The SRI group showed
a significant decrease of occipital alpha
power
in this
single subject compared with control
trials,
in which
the
light did not
flash
(Targ and Puthoff,
1974).
Approved For Release 2000/08/07
: CIA-RDP96-00788R001 300350001-0
Approved For Release 2000/08/07
: CIA-RDP96-00788R001 300350001-0
We attempted
to replicate
their finding and
to refine
the
technique.
This was
done,
first by reanalyzing data
tapes of their results;
second,
by attempting
to replicate
their results
in our
laboratory using the
same
subject;
and finally by attempting
to isolate
the variables necessary
to produce
the phenomenon at will.
We particularly examined whether
it
was necessary to have an observer
(sender)
present with the
light
flash
stimulus
and whether
it was helpful
to have
the subject guess whether
the
light was
flashing
or not.
In our
second
(final)
experiment,
we also
took extreme precautions
that
all procedures were double-blinded,
and
that
all previously measured electrode
sites were
included.
II
REANALYSIS
OF PREVIOUS DATA
We played
the EEG tapes
of Hella
Hamrnid,
gathered by Dr.
Rebert
of
SRI,
through our hard-wired alpha analysis
system.
The results
of
this
reanalysis
are provided
in Table
1,
They show power means
at
Oz
in
the
null condition
(no
flash,
0 Hz)
during
the
second 4-s epoch
at
t
=
2,08,
p <
0.05,
df
=
119.
This reanalysis confirmed
the published effect and
also ensured
the compatibility of
our
systems.
This system was used
in
all
of
the experiments
as well
as
in
the reanalysis
of the
SRI
data.
The specifications
and
logic
of
our analyzer system are given below.
The amplified EEG signals
are
taken from the amplifier outputs
and
lead
to
the alpha EEG filters.
Up
to
six channels can be accommodated.
The
filters were built by Kinetic
Technology,
Inc.,
of Mountain View,
California,
to high specifications:
Corner
frequencies
9.0 and
12.0
Hz,
48 dB down at
8.0 and
13.0 Hz with rejection over
the rest
of the stop-
band greater
than
dB,
and
pass-band ripple
less
than 0.2
dB p-p.
The
filters also had
a
30-to-60-mV dc offset.
Therefore,
a high-pass
filter
with
f =
8 Hz was
designed
that blocked
the dc offset and
satisfactorily
attenuated
the delta contamination,
comparing adequately with alpha data
generated by a
fast-Fourier- transform program on our
computer.
Alpha
levels
at
the
filter output are usually less
than 400 mV.
Operational
amplifiers
invert
and amplify the
filtered alpha
(gain =
50)
to provide
Approved For Release 2000/08/07
: CIA-RDP96-00788R001 300350001-0
Approved For Release 2000/08/07
: CIA-RDP96-00788R001 300350001-0
Table
REANALYSIS
OF DR.
REBERT'S TAPES
PLAYED THROUGH THE LANGLEY PORTER EEG ALPHA ANALYZER-
FEBRUARY
2 THROUGH
6,
1976
Analysis
of Variance with Repeated Measures
Treatment
Session
xO Hz
JL
xl6 Hz
1:1
578
490
n
3:1
465
397
n
2:1
553
466
2:3
232
174
2:4
308
236
Mean:
427.2
340.8
Results
of
t- Test
Langley Porter::
t -
2.08,
df =
119
P
SRI::
t
=
2.09,
df =
118
optimum
(near maximum)
input
to
the squared circuits.
The alpha
signals
are
squared by analog multipliers
(Analog Devices #533K)
to yield
instan-
taneous
power,
an approximation to
the
FFT computation.
The
transfer
function
is X2 /10,
with
a maximum of ±10 V input yielding +10 V output.
After
this
stage,
the signal processing
is commanded by
a microprogrammed
controller,
hard-wired
in TTL
logic,
except
for read-only memories
(ROMs)
that control
formatting in the digital
printer.
A master clock
is
synchronized with the power
line
(60 Hz).
When the experimenter
is ready to begin data acquisition,
he
selects
the summation time
(1
to 99
s) with
a two-digit
thumbwheel switch and
pushes
the
START button.
In our
experiment,
two 4-s
intervals were
chosen.
The START function resets
the summing integrators,
commands
the
Approved For Release 2000/08/07
: CIA-RDP96-00788R001 300350001-0
Approved For Release 2000/08/07
: CIA-RDP96-00788R001 300350001-0
%
printer to print
a
line of special characters signifying the beginning
of the record,
delivers
a 50-ms pulse
to the polygraph marker channel,
and connects the outputs of the sir squaring units
to the integrators.
Switching
is handled by reed relays
for lower
leakage.
Solid-state
switching devices were used
initially,
but leakage currents
(10
A)
were too high
for
the accuracy and stability required.
The integrators
make use of low-loss polystyrene capacitors,
and FET-input amplifiers
with ultra
low
(5
X
10' 12 A)
input offset current.
This design makes
it
possible
to use long summing Intervals
or interrupts with a drift
error
of no more than
!%•
After
the summation time has elapsed,
the outputs
of the six summing
integrators are sequentially connected to the analog-to-dlgital converter
(ADC)
by the analog multiplexer.
When each conversion is
finis
e
(
BCD)
the data
is parallel
loaded into shift registers.
The shift regis-
ters are then clocked by the controller
to send
the data
in digit
seria
form to the printer.
This being completed,
the next integrator
is con-
nected
to the ADC and
the process repeats.
This continues until all
six
integrators have been read and
the
summed power of each EEC lead
is
printed.
The digital printer
is
a MC4000 Monroe Datalog.
A fiberoptic
cathode ray tube exposes light-sensitive paper quickly and
(most important
for our research)
silently.
All standard alphanumeric characters
are
printable.
Next,
the controller commands
a line
feed
from the printer.
The
second
line of data
for
this
sample consists of the
log ratios of pairs
of integrators representing homologous
pairs
of brain electrodes.
T
e
log of the ratio rather than the ratio
is desired because
it
is
linear
around sero-e.g.,
a ratio of 2/1. -
1/2 = ±0.301.
The analog multiplexer
is then commanded
to connect
the
first two integrators to the two inputs
of the log ratio module.
Its output
is an analog voltage representing
the log ratio of the two channels
to
a 10-bit BCD number.
The printing
process
is
the
same with the addition of
a polarity bit Indicating which
hemisphere has
a higher output
for
the
task.
Approved For Release 2000/08/07
: CIA-RDP96-00788R001 300350001-0
Approved For Release 2000/08/07
: CIA-RDP96-00788R001 300350001-0
The process
is repeated
for computation of log ratios of the other
two pairs of integrators.
After
the last data are printed,
the controller
resets
the integrators,
then reconnects the squaring units
to their
inte-
grators.
One count
is added
to the
trial display register,
which tells
the experimenter
at
a glance how many epochs have been collected.
The
digitizing,
computation,
and printout takes
s,
primarily due to the
switching speed of the relays.
Ill
FIRST EXPERIMENT AT LANGLEY PORTER:
ATTEMPTED REPLICATION OF
SRI STUDY
A.
Method
1.
Subject
The
first experiment was conducted with a single
subject,
Bella Hammid,
who had been selected
from an initial group of four
female
and two male
subjects
tested by the
SRI group.
She was
selected because
she had had
the most consistent positive results
in their
study.
2.
Setting and Procedure
The
first experiment was conducted
in our EEG laboratory
at Langlay Porter
Inatitute.
The setting is diagrammed
in Figure
in
Part
One of this report.
The "sender"
sat before the photic stimulator
in a divided room separated by
a curtain from the
logic,
equipment,
and
monitors.
The number of people
in the room with the stimulator and the
"sender" varied from one to three.
Noise from the street and hallway
also varied.
The "receiver"
sat upright
in an isolated sound-attenuated
darkened metal chamber
located
in a laboratory adjacent
to the room in
which the
sender was
located.
The "receiver"
(subject) made no overt
responses
for
Set
1,
but was required
to press
a button to indicate her
guess
of trial
type about
s after
the warning tone
for
Set
2.
The
subject was
familiar with the nature of the experiment,
and was not
formally instructed
for each session.
Approved For Release 2000/08/07
: CIA-RDP96-00788R001 300350001-0
Approved For Release 2000/08/07
: CIA-RDP96-00788R001 300350001-0
The
sender and receiver were both presented with
a
one-
second warning tone that signalled
the beginning of
a
trial.
This was
immediately followed by the
light flashing
for
s at 16 Hr
in the
active condition,
and by no
flashes
in the null condition.
The
stimu-
lation period was divided
into 4-s
segments
for comparability with the
Rebert
study;
the first 4
s
following flash onset
(or null onset),
and
the Second
s starting with the sixth second from onset.
(The
fifth
second was blocked
from the analyser by the print cycle,
and we dis-
carded
the tenth second.)
A "set" was defined as at
least
100 acceptable
trials
of each type.
After
the first
set, minor modifications
(such as
a button to indicate guesses) were added,
and
a second set was run.
The
total number of acceptable trials was 212 of both types,
or 424 total.
In pretesting our equipment and procedure we used un-
selected subjects
such as
laboratory personnel,
in order
to test
the
adequacy of the protocol and
to determine whether
there was any cor-
related electronic
or mechanical interference from the apparatus.
In
these pilot sessions
of data acquisition there were no significant dif-
ferences between the null and
16 -Hz conditions.
3 ,
EEG Recording Procedure
Electrodes were placed at
C3,
C4,
01,
02,
and
0z,
all
referenced
to C.
The occipital
leads were not Identical
to the montage
used by the SRI group
(Os referenced to
linked mastoids),
but our montage
was used to provide more information about localisation within the
occipital region,
hemispheric
specialisation,
and possible related
activation at other
leads.
The EEG output
(J 6 )
of the Grass model
7 polygraph was
sent
to our data analysis
system,
described above,
and also to
a Hewlett
Packard M tape recorder,
through a Vetter multiplex system.
The
FM tape
provided the capacity for any possible
future reanalysis.
4.
Editing
The hard-copy EEG output
from the polygraph was edited
for artifact by experimenters blind
to the stimulus conditions
of any
Approved For Release 2000/08/07
: CIA-RDP96-00788R001 300350001-0
Approved For Release 2000/08/07
: CIA-RDP96-00788R001 300350001-0
trial.
Any trial showing evidence of electrode slippage
or of EMG
or
EOG contamination,
was deleted
from the data
set.
Trials were deleted after
the session
for
three reasons
only:
EEG artifact,
logic circuit
failure resulting in a breakdown in
the trial
sequence,
or out-of-jrange EEG power
(under 50
or above
1299
on
printout).
In each case,
the Linked
(or previously paired trial of any
trial discarded was also discarded along with data from all leads
for
all
s.
If more than 10 trials altogether were deleted
for any session of
40 trials,
the session was deleted.
Only in the case where it would make
the difference in saving or discarding a session were
the tapes
of the
session played back and reanalyzed at different gain levels
to recover
out-of-range epochs.
This was
done
for three sessions.
5.
Stimulus
The stimulus was
a battery-driven,
continuous -wattage
incandescent
lamp,
chopped by a continuously rotating apertured disc.
When the lamp was
lit,
the visible
stimulus was
a 16-Hz
flash.
In null
trials
the lamp was not
lit.
The stimulus was stationed
in a remote room
approximately
10 m from the subject.
6.
Control of Stimuli
The trials
in the experimental sessions were triggered by
pulses
from one of a
set of several
tapes
so that no human operator was
involved
in the triggering of the trials
in either
the
16-Hz
or
the 0-Hz
condition
(once the session had begun).
These tapes were made at
our
laboratory during the month preceding the experiment.
Randomized tables
for
the tapes were generated with
a
Texas
Instrument SR-51A electronic random-number generator.
Random
sequencies
of +s
(16 Hz)
and
-s
(0 Hz)
in lengths
of 40 were generated,
constrained by the requirements
that:
(1)
the trials be pseudorandomized
within each block of 10 trials
(i.e.,
groups
1-10,
11-20,
21-30,
and
31-40 each contain five of each kind of trial)
;
and
(2)
not more than
three trials
in a row of either type be allowed.
Approved For Release 2000/08/07
: CIA-RDP96-00788R001 300350001-0
Approved For Release 2000/08/07
: CIA-RDP96-00788R001 300350001-0
The
following procedure was
used:
+s and
-s were assigned
alternately within each block of
10 trials according
to
the random
sequences
of numbers generated by the key.
For example,
if the 21-30
block was being
filled,
and the random sequence of numbers was
14,
38,
45,
27:
first
a + would
go
to
1,
then a
-
to
4,
then + to
3,
-
to
8,
+ to
5,
-
to
2, + to
7,
etc.,
until
the block was
filled,
and then on
to the next block
(repeated digits were ignored).
Furthermore,
each +
and
the succeeding
- were linked
in the record
for editing purposes
(see
above)
#
Blocks
of +s and
-s were discarded
if it was
clear
that
they would include sequences
of
four or more consecutive +s
or
-s;
also,
if a sequence of four
or more +s
or
-s was created
from the juxtaposition
of two blocks
of
10,
the latter block was reversed
(+s changed
to
-s,
and
vice versa).
A single block of
10 trials was discarded because of cal-
culator
failure
in the middle of generating the block,
and another was
discarded because of a possible recording error
on the part
of the opera-
tor;
otherwise each trial
that was generated was
kept.
Control signals
for trials were recorded
on a
tape with
a 4-track Ampex stereo FM tape deck in direct mode,
with pulses
on one
channel
for
the 16-Hz condition and on another
for
the 0-Hz
condition.
The pulses were produced by two Grass
stimulators.
They were recorded
s
apart,
then checked afterward on playback.
The inter-trial
interval
was checked and
found
to be within
s of
s,
consistently,
with no
detectable systematic difference between conditions.
The
tapes were
played back on a Tandberg two-track stereo tape recorder
into
a
logic
circuit
that triggered the type of trial corresponding
to
the channel.
There were only rare failures
in trial triggering due
to errors
in the
trial
tapes
at any point during the experiment.
The coded tapes were selected by number with no pre-
arrangement
except
that
a different tape be used
for
each session m
a
set until all
tapes were used
once.
Only the operator of the logic
equipment had
the knowledge
of which tape was being used,
and no person
knew before any trial what
the trial
type would
be:
that information
was coded in the
tape.
The coded tapes produced 5-V pulses which,
mediated by the digital
logic,
triggered
the appropriate stimulus
type
Approved For Release 2000/08/07
: CIA-RDP96-00788R001 300350001-0
Approved For Release 2000/08/07
: CIA-RDP96-00788R001 300350001-0
for any trial.
Inter-trial interval was
fixed by
the spacing of pulses
on the
tape to be
±
s.
The command box of the photic stimulator,
when triggered,
produced
a
1-s warning tone
to both sender
and receiver
and,
following another
1-s
interval,
flashed a
light
for
s when a
16-Hz
trial was
ordered,
or did nothing if a null
trial was ordered.
The digital
logic
sent pulses
to turn the analyzer on and off at
s and
s,
respectively,
from the onset of the trial.
For each trial
the
digital
logic generated timing pulses
to be recorded
on the Hewlett
Packard
tape
for
use,
if necessary,
in off-line computer analysis
of the
data.
A
16 -Hz
trial was differentiated
from a 0-Hz
trial by the presence
of an initial 0.5-V positive pulse
for
the 16-Hz
trial.
This was
the
only electronic
signal differentiating the two conditions,
that entered
the recording area while the experiment was
in progress.
Operators
in
the recording area did not monitor
this
signal.
B.
Results
The means of summed alpha power
in arbitrary relative power
units are presented
in Table
2.
The differences
found to be significant
at greater than 0.05 are starred.
Significance levels were assigned by
F-tests
from repeated measures
of analyses
of variance.
The analyses
of variance were performed separately
for
each lead and epoch and
repeated across condition means.
The
SRI experiment reported
a decrement
at Oz-linked mastoids
at
16 Hz compared with the null
condition,
in the second 4
s.
At
our
Oz-Cz
lead we did not
find
a change
in the second 4
s
of either
set,
but
did
find a significant decrement in the
first
s
of the first
set.
None of the other
Oz comparisons attain significance and
the combined
Set
1 and
Set
first
s
is not
significant.
Therefore we did not
specifically confirm the
SRI
findings.
However,
01 and 02 showed
sig-
nificant decrement
in the first 4
s
of
Set
1,
and
showed enough
decrement
to reach significance in the
last 4
s
in
Set
2,
and m all
s,
with both
sets
combined.
Because our electrode montage was not
identical
with the
SRI montage,
our
first experiment showed
some decrements
at
other
locations.
Approved For Release 2000/08/07
: CIA-RDP96-00788R001 300350001-0
Approved For Release 2000/08/07
: CIA-RDP96-00788R001 300350001-0
Table
FIRST EXPERIMENT AT LANGLEY PORTER:
MEANS OF SUMMED EEG ALPHA
IN RELATIVE-POWER UNITS,
EXPRESSED AS NULL CONDITION/ 16 -Hz
CONDITION
Lead
Set
C3
C4
Oz
0-4
s
276/261
276/245
353/305*
425/336**
419/352*
Xo0
4-8
s
284/267
268/249
358/347
415/413
420/413
CuW
0-8
s
560/528
544/494
711/655
841/749
839/765
Set
0-4
s
305/288
389/386
469/461
534/536
532/563
,£5
ao
4-8
s
303/274
411/371
479/419*
511/477
484/516
DuW
0-8
s
608/562
800/757
948/880
1045/1013
1015/1079
Combined
Set
1 and
Set
2>:
Only
0-4
s
411/383
rCoo
4-8
s
419/383*
w
0-8
s
830/766*
^Significant at
p < 0.05.
Significant
at
p <
0.01.
IV
SECOND EXPERIMENT AT LANGLEY PORTER:
ATTEMPTED REFINEMENT
Since
the data from the
SRI study and our
first one were compatible
if not
identical,
we decided
to continue
to explore possible sources
of
variance
in this
phenomenon.
Specifically,
we pursued
the dependence
upon the "sender" and
the possible importance
of a trend
for
the trials
in which the subject correctly guessed that
the light was on or off to
show the greatest EEG power differences.
In addition,
we examined
the
differences between our montage of EEG sites
(01,
02,
C3,
C4 ref.
Cz)
and
the
SRI montage
(Oz
to linked mastoids);
and used more careful
pro-
cedures
ensuring double-blinding of experimenters and
subject.
Approved For Release 2000/08/07
: CIA-RDP96-00788R001 300350001-0
Approved For Release 2000/08/07
: CIA-RDP96-00788R001 300350001-0
A.
Method
1.
General
The method was
the same as
in the previous experiment,
although carried
out
in a new location
(see
Figure A-l
in the Appendix),
and with the addition of several refinements.
Sessions with a "sender"
alternated with sessions without
a "sender".
The subject was also given
a "pass"
or no-response option,
so that
she could indicate when she did
not
feel
sure of her response and would not hazard
a guess about the
stimulus
condition.
The pass option was signaled by the subject pushing
a button that marked the polygraph record,
so that we could discriminate
guess
trials
from non-guessed
ones.
There was an additional EEG channel
used,
so
that
in addition to recording from
01,
02,
C3,
C4,
and
Oz
referenced
to
Cz,
as
in our
first experiment,
we also recorded
the
Oz
referenced
to linked mastoids configuration used by the
SRI
group.
The subject
("receiver") was again Ms.
Hammid,
and
the
"sender" was always
R.
Targ.
2.
Double-Blind Procedures
In addition to generating the stimulus-condition sequence
types,
we ensured that no one had
information concerning the trial-type
sequence.
The person who generated
the tapes
gave them to another member
of the laboratory staff
for
labeling:
A,
B,
C,
etc.
A third staff mem-
ber chose
a tape at random before the session.
No one had knowledge of
the trial-type sequence until after
the session was completed and
the
stimulus marker sequence played back from the Hewlett-Packard recorder.
The operator who played the tape coded
the trial-type neutrally
(i.e.,
A and
B rather
than + and
-).
The operator who did this
step knew the
code and was not allowed
to handle data
further.
The personnel who
analyzed
the data were blind
to which of the two labeled conditions
cor-
responded
to the actual trial-type.
The trial-type was monitored with a light-sensitive
recorder--i.e.,
no one was
in the room during trials without a "sender".
During "no-sender"
sets,
Mr.
Targ spent
the duration of the
set with one
Approved For Release 2000/08/07
: CIA-RDP96-00788R001 300350001-0
Approved For Release 2000/08/07
: CIA-RDP96-00788R001 300350001-0
of the experimenters.
He did not know in advance whether
a
given set
would be "sender"
or "no-sender."
B,
Results
1.
General
The means of summed alpha power are presented
in Table
and Table
4.
Table
3 lists
the means
from all
trials,
showing the
trials with a sender separately from those without a
sender.
Table 4
shows the means
from only those trials
on which the subject guessed
the
stimulus
condition.
Significance levels were again assigned from F-tests
from repeated measured of analyses of variance performed separately
for
each
lead,
repeated across
condition.
This experiment
shows an effect opposite
that of
the
SRI
experiment and
our
first
study:
instead of alpha power decreasing
during the active condition,
it increased.
The effect reaches
signifi-
cance only at
Oz referenced
to
Cz,
although the direction
is the same at
other
leads.
Also
of interest
is
the finding that
for
the
SRI montage,
Oz referenced
to linked mastoids,
there was no significant difference
between stimulus conditions.
The only F-value
to reach the
0.05
level
is
that of
Oz referenced
to Cz
(F =
4.33),
no
sender.
If this
is
com-
bined with the trials with
sender
(which
is not
significant by itself—
F =
2.647),
the overall
F for
0-8
s
is
7.03,
p < 0.01.
However,
this
is
a different
site than that used
for
the original
SRI
finding,
and
our
first experiment,
and in the opposite direction.
2.
Guess Effect
For trials
in which the subject was required
to guess
the stimulus condition
(guess
trials),
our
first experiment showed
a
tendency
to exhibit
a greater alpha decrease than
in trials in which
the subject
did not
guess.
Trials
in which the subject correctly
guessed
the stimulus condition showed
this
tendency to a greater
degree.
We investigated this tendency more rigorously in the second experiment.
Approved For Release 2000/08/07
: CIA-RDP96-00788R001 300350001-0
Epoch
Epoch
Means
F
Values
Means
F
Values
Approved For Release 2000/08/07
: CIA-RDP96-00788R001 300350001-0
Table
SECOND EXPERIMENT AT LANGLEY PORTER:
ALL TRIALS,
SENDER VS NO SENDER MEANS AND
F VALUES
OF SUMMED EEG ALPHA
IN RELATIVE POWER UNITS,
MEANS EXPRESSED AS NULL CONDITION/ 16 -Hz CONDITION
(Seven Sessions,
121 Trials
in Each Condition)
Lead
Oz
to
Linked
C3
C4
Mastoids
Sender---All
Trials
0-4
s
0.073
1.687
0.041
0.744
1.071
0.182
4-8
s
0.039
2.556
0.032
0.000
1.221
0.024
0-8
s
0.089
3.853
0.107
0.116
2.647**
0.017
0-4
s
479/486
484/517
275/264
320/306
408/439
439/449
4-8
s
428/432
441/480
253/255
280/281
384/410
415/410
0-8
s
907/919
925/997
527/519
595/586
792/849
854/860
No Sender--All Trials
0-4
s
2.760
1.560
1.912
0.902
2. 750
0.364
4-8
s
0.374
0.541
0.046
1.020
2.440
0.700
0-8
s
2.090
1.869
0.611
0.001
4.330*
0.770
0-4
s
404/442
401/491
262/284
335/318
382/423
499/521
4-8
s
399/411
441/461
271/267
297/314
385/422
466/498
0-8
s
802/853
902/952
533/551
633/632
766/844*
966/1018
Significant
at
p <
0.05,
Significant at
p <
0.01,
F > 3.93
(1,
120).
F > 6.84
(1,
120).
Approved For Release 2000/08/07
: CIA-RDP96-00788R001 300350001-0
Approved For Release 2000/08/07
: CIA-RDP96-00788R001 300350001-0
Table 4
SECOND EXPERIMENT AT LANGLEY PORTER:
GUESS TRIALS
ONLY,
SENDER VS NO SENDER
MEANS AND
F VALUES OF SUMMED EEG ALPHA
IN RELATIVE POWER UNITS,
MEANS EXPRESSED AS NULL CONDITION/ 16-Hz CONDITION
Lead
Oz
to
Linked
C3
C4
Oz
Mastoids
Sender- -Guess
Trials
w
<D
0-4
s
0.003
0.470
0.642
1.081
0.833
0.017
i—
i
4-8
s
0,312
0.676
0.005
0.002
0.097
0.758
>
(JCh
0-8
s
0.083
1.058
0.330
0.402
0.614
0.422
0-4
s
489/491
495/514
268/253
318/300
415/438
450/447
W
cd
4-8
s
445/432
461/482
258/257
284/285
400/408
436/408
0)
S3
0-8
s
934/922
956/997
525/510
602/585
815/846
886/855
211
Trials:
104 null,
107
16 Hz
No Sender--Guess Trials
W
d)
0-4
s
1.900
0.752
1.182
1.638
1.894
0.044
r—1
4-8
s
0.344
0.490
0.013
0.563
1.755
0.901
>
1*4
0-8
s
1.603
0.840
0. 663
0.168
3.069
0.533
0-4
s
413/447
475/498
261/278
340/314
387/423
512/520
w
rt
4-8
s
408/420
451/469
270/272
301/314
392/426
481/519
0)
Jfi
0-8
s
820/868
928-963
531/550
641/628
779/849
993/1040
211
Trials:
106 null,
105
Hz
Approved For Release 2000/08/07
: CIA-RDP96-00788R001 300350001-0
Approved For Release 2000/08/07
: CIA-RDP96-00788R001 300350001-0
The "pass option," described above,
to eliminate
forced guessing w
the subject was not certain,
made
it
less
likely that incorrect
guesses
would bo included.
Comparison of Table 4 to Table
3 shows
that the effect of
guessing certainly does not increase the effect noted at
Os.
Alpha
increases
in the active condition compared
to
the null condition were
not significant.
The logical inference of this
is
that
the pass
trials
should show a greater difference than "guess" or "all"
trials.
Ta
shows the pass
trials.
They do exhibit greater differences in the same
overall direction of this experiment,
an alpha increase in the active
Table
SECOND EXPERIMENT AT LANGLEY PORTER:
PASS TRIAL MEANS,
SHOWN AS NULL. CONDITION/ 16 Hz CONDITION
T.ead:
Referenced
to
Cz
Sender- -Passes
0-4
s
420/468
423/523
rd
331/475
Means
Oo
Ql,
4-8
s
360/427
w
0-8
s
780/895
754/998
0-4
s
0.90
0.81
Ratios
dJ
0.70
of
oo
4-8
s
0.84
Means
M-iw
0-8
s
0.87
0.76
No Sender--Passes
0-4
s
366/382
393/417
rC
393/378
Means
oo
4-8
s
357/343
w
0-8
s
723/725
786/795
0-4
s
0.96
0.94
Ratios
dJ
1.04
of
o0e^
4-8
s
1.04
Means
**
Pxl1
0-8
s
1.00
0.99
Oz
to
Linked
C3
C4
Oz
Mastoids
316/356
328/344
353/454
403/440
227/256
268/246
301/428
308/406
543/612
596/590
654/882
711/846
0.89
0.95
0.78
0.92
0.89
1.09
0.70
0.76
0.89
1.01
0.74
0.84
277/307
321/323
345/399
364/516
269/206
299/315
303/397
333/374
546/513
620/638
648/796
697/890
0.90
0.99
0.86
0.71
1.31
0.95
0.76
0.89
1.06
0.97
0.81
0.78
Approved For Release 2000/08/07
: CIA-RDP96-00788R001 300350001-0
Approved For Release 2000/08/07
: CIA-RDP96-00788R001 300350001-0
condition,
opposite
to what was
scan in the first study.
Ihrther post-
hoc statistical tests were not performed on the pass
trials because the
differences were clearly too small to reach significance.
A very con-
servative criterion
is required
for
a post-hoc analysis
of an isolated
observation
for which there are previous data in the opposite direction.
The second
factor
in the trend toward a guess effect
in
the first experiment was an even greater alpha difference on those trials
in which the subject guessed correctly.
The correct
guesses
for
the
second experiment are shown in Table
6.
The correct
guesses without a
sender
show a small alpha increase in the active condition compared to
Table
SECOND EXPERIMENT AT LANGLEY PORTER:
CORRECT GUESS TRIAL MEANS,
SHOWN AS NULL CONDITION/16-Hz CONDITION
Lead
:
Referenced
to Cz
0z
to
Linked
C3
C4
Oz
Mastoids
Sender-.-Correct Guesses
481/445
0-4
s
518/463
561/497
291/233
348/276
463/407
Means
oo
4-8
s
465/429
473/492
277/236
303/292
417/407
387/459
w
0-8
s
983/892
1034/989
568/469
651/568
880/814
868/904
0-4
s
1.12
1.13
1.25
1.26
1.14
1.08
Ratios
of
-doo
4-8
s
1.09
0.96
1.17
1.04
1.02
0.84
Means
cuw
0-8
s
1.10
1.05
1.21
1.15
1.08
0.96
Nn Sender --Correct Guesses
529/540
0-4
s
425/449
469/505
284/256
356/298
386/420
Means
•doo
4-8
s
421/411
456/453
302/262
331/306
394/406
496/585
04H
0-8
s
846/860
925/958
586/518
687/604
780/826
1025/1125
0-4
s
0.94
0.93
1.11
1.19
0.92
0.98
Ratios
of
•doo
4-8
s
1.02
1.01
1.15
1.08
0.97
0.85
Means
ow
0-8
s
0.98
0.97
1.13
1.14
0.94
0.91
Approved For Release 2000/08/07
: CIA-RDP96-00788R001 300350001-0
Approved For Release 2000/08/07
: CIA-RDP96-00788R001 300350001-0
the null condition
(not
significant).
Correct guesses with a
sender
show a small alpha decrease compared
to the null condition,
in the
direction of the
first experiment,
but too small to be significant.
V
DISCUSSION
in two studies,
one at
SRI and one in our
laboratory,
a decrease
in
EEC alpha power was observed as
a function of remote photic
stimulation,
but at different
scalp locations and in different time periods
following
the stimulus
onset.
The third study,
on our
laboratory,
showed an
in-
crease
in alpha power at another
site and failed to replicate
the
original
finding.
Dr.
Edwin May of SRI has done
a
full power spectral analysis
of
these data and reports
that his analysis
shows results similar
to ours.
We also observed that the subject's alpha frequency seemed
to be slightly
lower in the second experiment than the
first,
and Dr. May
s analysis
confirmed
this.
However we
see no easy way to account
for the negative
or inconsistent experimental results
in terms
of frequency changes.
We
cannot account
for
this
frequency change.
The subject underwent major
pelvic
surgery in the three months between our
first and second experi-
ments,
but there
is no apparent reason to relate this
to the EEC change.
Statistical analysis of these data necessitated many significance
tests on the same subject.
One must always question the independence
of such
tests,
and also keep
in mind
that 5% of them will be significant
if the 0.05
level of confidence
is adopted.
In addition,
repeated
measures on one subject and simultaneous measurements
from different
leads always brings
the independence of these measures
into question.
If
the findings were replicable,
the statistical questions would
be
less
important.
However,
since there are many possibilities and we
failed
to replicate either our earlier finding or the
SRI results,
it
is necessary to take a more conservative statistical position.
The
three separate experiments
all
show effects
in the occipital
cortex,
but
it
is not
the same effect,
either in direction or
site.
We believe the
Approved For Release 2000/08/07
: CIA-RDP96-00788R001 300350001-0
Approved For Release 2000/08/07
: CIA-RDP96-00788R001 300350001-0
three experiments
should not, therefore,
be lumped together as jointly
supporting each other:
They could
just
as easily be taken as
jointly
nullifying each other.
In conclusion,
on each occasion,
alpha changes occurred
that differ
from chance,
but we could not reproduce the same
effect,
in either
direction or
site.
There remains
the possibility that a useful pheno-
menon exists here,
but if
so,
we have clearly not
isolated
the variables
necessary
to produce
it at will.
Approved For Release 2000/08/07
: CIA-RDP96-00788R001 300350001-0
Approved For Release 2000/08/07
: CIA-RDP96-00788R001 300350001-0
Appendix
SRI OPTICAL ISOLATION EXPERIMENTS AT LANGLEY PORTER
Approved For Release 2000/08/07
: CIA-RDP96-00788R001 300350001-0
Approved For Release 2000/08/07
: CIA-RDP96-00788R001 300350001-0
Appendix
OPTICAL ISOLATION EXPERIMENTS AT LANGLEY PORTER
1,
Introduction and
Summary
As described
in Sections
I-B and
III-A of this report,
the purpose
of these measurements was
to determine whether
there exists any measur-
able
light
leakage between the
stimulus room in which a chopped
light
source operates,
and
the subject room in which EEG recordings are being
made.
Using phase-sensitive detection,
a photomultiplier with an S-20
photocathode,
and a synchronously chopped
light
source,
we obtained
a
-15
system sensitivity of
X
W/cm
with unity signal- to-noise ratio,
limited by photo-tube dark current.
This
sensitivity,
in W/cm
,
is
-13
X
of the flash lamp
intensity used
in our experiments
(125 dB
down).
Our
findings using
this
equipment are as
follows:
(1)
In order
to obtain
a measurable
light
leakage signal
it
was necessary
to open
two of the three doors
separating
the stimulus room from the subject room
(see
Figure A-l)
and direct
the output
of the
flash lamp on the door
frame
of the subject room.
Under
these conditions
a
signal
could be detected with 20:1 signal- to-noise ratio by
the
photomultiplier placed
in the subject
chair.
(2)
When any
two of the three doors between the subject room
and
the flash
lamp were closed,
no signal could be
detected,
up
to
the measuring capability
of the apparatus,
with a
10-s
integration time.
(3)
To examine
the possibility of light transmission through
the air conditioning
ducts,
we placed
the photo-tube
detector
in the duct
in the subject room and directed
the
output of
the flash lamp on the duct in
the stimulus
room.
Again,
no detectable signal was
found.
From this investigation we
find
that
to the
limit of our measurement
capability and under
the conditions defined by
the experimental
protocols
and
geometry,
there was no
light
leakage between
the rooms
in question;
thus we conclude that
the experimental
findings
of this program cannot be
attributed
to
light
leakage.
Approved For Release 2000/08/07
: CIA-RDP96-00788R001 300350001-0
Approved For Release 2000/08/07
: CIA-RDP96-00788R001 300350001-0
2.
Laboratory Arrangement
The laboratories
evaluated
in this experiment consist of two
groups
of rooms
on either
side
of a hallway.
(See
Figure A-l.)
The doors
of
the
two laboratories
face each other
as
they open onto
a hall.
The
stimulus room housing the lamp
is
a single room with one door.
The
sub-
ject room
is
entered
from the hall,
by first passing through a control
room housing EEG recording equipment.
The subject room
is considered
a
darkroom,
and has windows
on the outer wall
(opposite the control room)
that
are taped and boarded
up.
A small but visible amount
of
light
enters
the room around
the tape.
The room is
separated
from the control
room by
a wooden door having plastic weather stripping on
its
edges,
as
have
the outer doors of both
labs.
Thus,
from where
the subject
sat
in
the dark room,
the
light
from the stimulus room would have had
to pass
through three closed
and sealed doors
to reach her.
3.
Apparatus
The
light-detecting system used
in this measurement
is
shown in
Figure A-l.
An electron multiplier photo-tube
(RCA 7265)
is
powered by
an 1800-V dc
power
supply,
and
its anode current
is measured across
a
100-kilohm resistor.
The voltage
thus developed
goes
to
the
input channel
of
a PAR
(Princeton Applied Research)
phase-sensitive detector,
having
a
tuned
input
filter,
phase-sensitive amplifier,
and variable time con-
stants,
We derive
the reference signal
for
the amplifier
from a
small
photodiode
taped
to
the face of the chopped
light source in
the stimulus
room.
The chopping
frequency is
Hz,
The
output
of
the light
source was measured with
a
16-junction
Eppley thermopile and
a microvoltmeter.
This measurement
gave an
intensity of
15 mW/cm
at
10 cm from the
light
source.
Using this now-calibrated
light
source,
together with calibrated
neutral density
filters,
we measured
the sensitivity of
the phototube
-15
and phase-sensitive detector
to be
x
W/cm
,
with an integrating
time constant
of
s.
Approved For Release 2000/08/07
: CIA-RDP96-00788R001 300350001-0
Approved For Release 2000/08/07
: CIA-RDP96-00788R001 300350001-0
SEALED
FIGURE
A-1
FLOOR PLAN AND APPARATUS FOR LIGHT-LEAKAGE MEASUREMENTS
Approved For Release 2000/08/07
: CIA-RDP96-00788R001 300350001-0
Approved For Release 2000/08/07
: CIA-RDP96-00788R001 300350001-0
4.
Results
In these experiments
the conditions were exactly as
they were during
the actual EEG experiments described in detail
in Section IV-A of Part
of this report.
In particular,
there was
a small amount
of outside day-
light
leaking into the subject room through the electrical
tape used
to
seal
the window cracks.
This was quite a small amount of
light,
amounting
to approximately six times
the dark current of the phototube-- i.e.,
x
*
W/cm^.
This amount of light
is barely detectable
to the dark-
adapted
eye,
but does
give rise
to incoherent
shot noise in the phototube,
increasing
the magnitude of the minimum detectable signal.
The subject room and
the light stimulus room are connected
to a
common air-conditioning
system.
The air-conditioner ducts make eleven
right-angle bends
in traversing the
30 feet between the two rooms,
and
this ducting was
a prime suspect
for possible
light leakage between the
two rooms.
To determine
the presence of such
leakage,
the phototube was
placed
inside the duct in the subject
room,
and
the light
stimulator had
its output directed
at
the duct
in the stimulus room
(even though this
was not
the condition during actual experiments,
when
it was pointed
toward
the side wall of the room).
With
the phototube in the duct,
its
background was no
longer determined by the ambient
light
in the
room,
but rather by phototube dark current,
giving
a phase- sensitive amplifier
-15
reading of 5
p,V,
corresponding to
X
W/cm
.
This
signal was not
affected by the presence
or absence of
light from the
flash lamp directed
at the other
end
of the air-conditioning duct.
In measurements with the flash lamp directed along
a vector across
the intervening hall
toward
the door
frame and closed door of the
experimental
room,
no position or manipulation
of the flash
lamp produced
any effect whatever
on the output of the phase-sensitive detector.
A
signal
could
be detected
only when both of the
two hall doors
of
the
laboratory rooms were
left open to allow the
light
to leave and
enter
the rooms
(a condition counter
to those
set up during experimentation).
The signal
in this case was twenty times
the shot noise background due
to ambient
light in the darkroom,
with its door closed.
Approved For Release 2000/08/07
: CIA-RDP96-00788R001 300350001-0