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THE JOURNAL OF ALTERNATIVE AND COMPLEMENTARY MEDICINE
Volume 12, Number 1, 2006, pp. 31–38
© Mary Ann Liebert, Inc.
Anatomic Characterization of Human Ultra-Weak
Photon Emission in Practitioners of Transcendental
Meditation™ and Control Subjects
EDUARD P.A. VAN WIJK, Ph.D.,
1
HEIKE KOCH, M.A.,
1
SASKIA BOSMAN, Ph.D.,
1
and ROELAND VAN WIJK, Ph.D.
1,2
ABSTRACT
Background: Research on human ultra-weak photon emission (UPE, biophoton emission) has raised the
question whether a typical human emission anatomic percentage distribution pattern exists in addition to indi-
vidual subject overall anatomic summation intensity differences. The lowest UPE intensities were observed in
two subjects who regularly meditate. Spectral analysis of human UPE has suggested that ultra-weak emission
is probably, at least in part, a reflection of free radical reactions in a living system. It has been documented that
various physiologic and biochemical shifts follow the long-term practice of meditation and it is inferred that
meditation may impact free radical activity.
Objective: To systematically quantify, in subjects with long-term transcendental meditation (TM) experi-
ence and subjects without this experience, the UPE emission of the anterior torso, head and neck plus the hands
in an attempt to document the differences by the two groups.
Subjects: Subjects were 20 men reported to be healthy and nonsmokers. Each of the subjects in the medi-
tation group had practiced TM twice daily for at least the past 10 years.
Methods: UPE in 20 subjects was recorded in a dark room using a highly sensitive, cooled photomultiplier
system designed for manipulation in three directions. The protocol for multisite registration of spontaneous
emission includes recording of 12 anatomic locations of anterior torso, head, and hands.
Results: Data demonstrate emission intensities that are lower in TM practitioners as compared to control
subjects. The percent contribution of emission from most anatomic locations was not significantly different for
TM practitioners and control subjects. Exceptions are the contributions of throat and palm.
Conclusion: In subjects with long-term TM experience, the UPE emission is different from control subjects.
Data support the hypothesis that free radical reactions can be influenced by TM.
31
INTRODUCTION
U
ltra-weak light, spontaneously emitted from humans is
commonly referred to as “human biophoton emission.”
The intensity of this emission in the visible range of the spec-
trum is estimated to be on the order of less than 10
2
pho-
tons/per cm
2
body surface.
1–5
It is thus, even though in the
visible spectrum, not visible to the naked eye and cannot be
captured with commonly used optical detectors. Ultra-weak
photon emission is a constituent of the metabolic process of
any living system. The wavelength spectrum of this emis-
sion recorded within the sensitivity of the multiplier is in the
range of 450 to 630 nm, corresponding with lipid peroxida-
tion processes documented from animal tissue.
6–8
To study topographic variation in emission intensity, low-
noise photomultipliers systems capable of single photon
1
International Institute of Biophysics, Neuss, Germany.
2
Faculty of Biology, Utrecht University, Utrecht, The Netherlands.
counting with high signal stability have been constructed
that can be positioned over a subject laying supine.
3
Van
Wijk and Van Wijk
4,9
described a protocol for quantitative
multisite recording of subjects. Data demonstrated the vari-
ability in patterns among subjects. Some generic features
were observed: (1) the fluctuation of photon counts over the
body was lower in the morning than in the afternoon; (2)
the thorax-abdomen region emits the lowest and most con-
stant emission; and (3) the upper extremities and the head
region emit the highest levels and increase during the day.
The existence of a generic pattern of anatomic distribution
of ultra-weak photon emission was also suggested from re-
cent studies using a highly sensitive charge-coupled device
(CCD) imaging system, developed by Kobayashi.
10
In the search of the preceding protocol for an explana-
tion of the quantitative differences among subjects, it was
learned that the two subjects with lowest emission happened
to be experienced meditation practitioners.
11
Long- as well
as short-term physiologic effects of meditation have been
described for over 30 years.
12
Long-term effects on aging
processes
13
and in subjects with chronic diseases have been
reported.
14,15
Transcendental Meditation (TM) has been im-
plicated in impacting free radical activity as demonstrated
by documenting lower blood peroxide levels.
16
Davidson et
al.
17
demonstrated emission alterations of left anterior acti-
vation as well as antibody titers to influenza vaccine of sub-
jects who meditated 45 min daily for 6 weeks.
The preceding publications can serve as a foundation to
raise the hypothesis that human photon emission may be in-
fluenced by regular use of meditation. Meditation refers to a
family of techniques that share a conscious attempt to not
dwell on discursive, ruminating thoughts but rather to focus
attention in a nonanalytic way.
18
People who meditate often
develop their own mix of techniques. These can embrace
mindfulness meditation, concentrative meditation, passive
breathing exercises, yoga stretching, imagery, and autonomic
training. In general, it is difficult to estimate exactly which
part of the technique is responsible for the results of the med-
itation experience. The present study examined the biopho-
ton emission from the upper frontal torso, head, neck, and
hands of 10 subjects who practiced specifically Transcen-
dental Meditation™ as taught by Maharishi Mahesh Yogi.
MATERIALS AND METHODS
Subjects
The study included 10 male experienced practitioners of
TM (mean age 50.4 4.3 y) and 10 male control subjects
without experience with any form of meditation (mean age
50.1 14.8). Each of the subjects in the TM group had prac-
ticed meditation for at least 10 years. It is a mental tech-
nique practiced for 20 min twice a day sitting easily with
the eyes closed. The technique is taught by Maharishi Ma-
hesh Yogi and learned from an authorized teacher under the
auspices of the Maharishi’s Global Administration Through
Natural Law, Ltd. Some of the practitioners also practiced
the more advanced TM-Sidhi program. Subjects practiced
no other meditation technique.
All subjects were selected by posting a flyer on different
internet news groups recommended by TM headquarters in
The Netherlands. The subjects by self-report were healthy
and free of medications. They also were interviewed to ex-
clude any physical or emotional disorder. Exclusion criteria
included the use of any antioxidant (i.e., vitamins E and C).
Subjects ranged in age from 20 to 65 years. Written consent
to participate in the study was obtained after they were thor-
oughly informed about the research. Each subject was mea-
sured with photomultiplier technology only once.
Recording human emission with the photomultiplier
The photomultiplier (9235 QB, selected type; Electron
Tubes Limited, Ruislip, England, previously EMI) with a
range of 200 to 650 nm was designed for manipulation in
three directions. It was mounted in a sealed housing under
vacuum with a 52-mm diameter quartz window maintained
at 25°C to reduce the dark current (electronic background
noise). Dark current was measured before and after each ex-
periment. During the experimental period, the average back-
ground noise was 5.2 0.3 cps (counts per second). A
spacer (a ring 7 cm high) at the front of the photomultiplier
tube allowed the measurement of a 9-cm diameter anatomic
area at a fixed distance. The front ring was vented inside,
avoiding the condensation of moisture in the quartz window.
The photomultiplier was hung in a dark room in a man-
ner designed for manipulation in three directions. The walls
and ceiling of the dark room were covered with mat black
paint. The inner size of the dark room was 2 m 1.5 m
2 m with an average temperature of 20°C. The room could
be vented; the resulting small fluctuations in room temper-
ature gave negligible change in the dark current of the pho-
ton-counting device. A bed was positioned in the dark room.
The dark room was juxtaposition to the control room, which
housed the computer system.
Subjects were commonly recorded between 11
AM
and 2
PM
. Before measurement, subjects were shielded from am-
bient light for at least 1 hour. The shielding was an effort
to avoid delayed luminescence interference from previous
exposure to daylight or artificial light prior to recording.
9
During this period subjects remained in the red dim light of
the control room. Subjects then walked into the dark room
and were positioned on the bed for at least 10 minutes. The
photomultiplier tube was placed above the body, the ring at
the front port of the photomultiplier touching a particular
anatomic area. The duration of each recording was 120 sec-
onds, consisting of 2400 time intervals of 50 ms. Maximum
duration of the measurement cycle inside the dark room was
45 minutes.
VAN WIJK ET AL.
32
The anatomic locations used for recording were selected
in such a way that the distribution of emission along the lon-
gitudinal ventral axis and the left and right hands over both
palm and dorsal sides were recorded. Exceptions were made
at the mouth and navel areas. Both left and right sides were
measured to provide homogeneous skin assessment.
Data analysis
Statistical analysis of photon count data was performed
with Statistica 6.1 (StatSoft, Tulsa, OK, version 2004).
Groups were compared by exact nonparametric two-sample
Wilcoxon tests. In contrast to t-tests, these tests neither as-
sume that the data are normally distributed, nor assume that
the variances in both groups are equal. Consequently,
Wilcoxon tests do not test whether two groups do differ only
by a shift of means but rather the more general hypothesis
whether high values are more likely in one group than in
the other.
RESULTS
Anatomic locations for biophoton recording
The pattern of sites for multisite registration of sponta-
neous emission includes recording of 12 anatomic locations:
frontal torso, head, and hands (Fig. 1). The pattern corre-
sponds with CCD images of a previous dark-adapted sub-
ject revealing the topography of spontaneous ultra-weak
photon emission (Fig. 2). CCD images were obtained in the
laboratory of M. Kobayashi (Department of Electronics, To-
hoku Institute of Technology, Sendai, Japan).
The large anatomic CCD image of the superior
anatomic area (see Fig. 2, left side) was obtained by
recording from a subject continuously for 30 min with
cryogenic cooled CCD camera at a distance of 100 cm.
10
As illustrated in the image, photon emission intensity
around the face and neck was highest and gradually de-
creased over the torso and subsequently over the ab-
domen. A gradual decrease in intensity also was docu-
mented from the superior central torso to its lateral
dimensions. The CCD image of the hands (see Fig. 2,
right side) was obtained by recording at approximately
40 cm. It is interesting to note the strong emission from
the nails, and its inequality for the different fingers. The
images illustrate a rather homogeneous photon distri-
bution over the palm and back of the hand.
All selected locations are full skin areas with reasonable
homogeneous distribution of photon emission. The various
anatomic areas represent the wide range of emission inten-
sities: low over the abdomen to high over the palm of the
hand and forehead.
PHOTON EMISSION IN TM PRACTITIONERS AND CONTROLS
33
FIG. 1. Anatomic locations used for multisite registration of spontaneous emission of a group of male subjects.
Multi-site registration of spontaneous emission
from anatomic locations of TM practitioners
and control subjects
The recordings at 12 anatomic locations were carried out
with 10 TM practitioners and 10 control subjects. Each
recording consisted of 2400 consecutive intervals of 50 ms.
Electronic background was measured before and after the
measurement of each subject. Because the recording of the
subjects was performed over a period of 2 months, the elec-
tronic background varied slightly at times. Average back-
ground noise in this period was 5.2 0.3 cps; values ranged
between 4.9 0.3 cps and 5.7 0.4 cps. Mean emission of
each of the 12 anatomic locations of each subject was de-
termined after subtracting the background value of the cor-
responding subject’s recording session. The average inten-
sity was calculated for the group of 10 TM practitioners of
each of the 12 specific anatomic locations and for the group
of 10 control subjects (Table 1).
TM practitioners demonstrated for all recorded anatomic
locations lower emissions than control subjects. The aver-
age photon emission in the TM group was 35% lower than
the control group. The emission of the throat, forehead, and
heart location were decreased 52%, 44%, and 45%, respec-
tively; the palm of the right and left hand 16% and 23%, re-
spectively. The large differences demonstrated for the solar
plexus and heart locations on the torso, and for the throat,
right cheek, and forehead locations on the head were sig-
nificant as confirmed by the nonparametric Wilcoxon test.
Although TM practitioners demonstrated lower mean emis-
sion from both sides of the hands, the differences demon-
strated for locations on the hand were not found to be sta-
tistically significant.
A typical pattern of emission of TM practitioners
and control subjects
Figure 3 portrays the contribution of each anatomic lo-
cation to total emission for each subject. Data demonstrate
that the sum of emissions from 12 anatomic locations of
each subject could differ approximately five times between
subjects; total emission can fluctuate between 50 and 235
cps. For both TM practitioners and control subjects, the per-
cent emission contribution of each anatomic location to to-
tal emission for each group is represented in Table 2. The
contributions of almost all locations to total emission are
very similar for both groups. Exceptions are the contribu-
tions of throat and palm of the hand to total emission. Data
demonstrate higher contributions of hand emission and
lower contribution of throat to total emission in TM practi-
tioners as compared to control subjects (Wilcoxon test; p
0.05). This suggests that superimposed on the “common”
human emission pattern, a fluctuation occurs in TM practi-
tioners.
DISCUSSION
This study presents evidence that the intensity of photon
emission is less in experienced TM practitioners. For both
VAN WIJK ET AL.
34
FIG. 2. Biophoton emission images of a human subject. Left panel: Biophoton image of ventral torso. Right panel: Biophoton im-
age of palm (left) and dorsal (right) of the hands measured with the CCD imaging system. Biophoton images were taken with obser-
vation time of 30 min.
0
0
5
10
15
20
25
30
35
50
Emission of location (cps)
100
Abdomen-right
Solar plexus
150 200 250
0
0
5
10
15
20
25
30
35
50
Emission of location (cps)
100 150 200 250
Throat
0
0
5
10
15
20
25
30
35
50
Emission of location (cps)
100 150 200 250
Cheek-right
0
0
5
10
15
20
25
30
35
50
Emission of location (cps)
100 150 200 250
Hand palm-right
0
0
5
10
15
20
25
30
35
50
Emission of location (cps)
100 150 200 250
0
0
5
10
15
20
25
30
35
50 100
Abdomen-left
150 200 250
0
0
5
10
15
20
25
30
35
50 100
Heart
150 200 250
0
0
5
10
15
20
25
30
35
50 100
Forehead
150 200 250
0
0
5
10
15
20
25
30
35
50 100
Cheek-left
150 200 250
0
0
5
10
15
20
25
30
35
50 100
Hand palm-left
150 200 250
Hand dorsal-right
0
0
5
10
15
20
25
30
35
50
Emission of location (cps)
100 150 200 250
0
0
5
10
15
20
25
30
35
50 100
Hand dorsal-left
Total emission (cps)
Total emission (cps)
150 200 250
FIG. 3. Contribution of photon emission from individual anatomic locations to total emission for each subject. X-axis indicates total
photon emission (counts/s); Y-axis indicates photon emission (counts/s) for each anatomic location. Each point represents one subject
(gray square TM practitioners; black circle control subjects).
VAN WIJK ET AL.
36
groups, the abdomen emits the lowest intensity; this gradu-
ally increases rostally and is the highest around the face.
Higher intensity also was documented for the palms. Data
also illustrate that human subjects have a “common” pattern
of ultra-weak photon emission. This pattern of emission was
not completely identical for TM practitioners and control
subjects. TM practitioners demonstrate higher contributions
of hand emission and lower contribution of throat emission
to total emission as compared to control subjects. Data were
derived from registrations using multisite recording with a
hanging and movable photomultiplier system. CCD imag-
ing of different subjects in Japan validates the intensity vari-
ances as supported by images of the superior anterior (in-
cluding head and neck) anatomic parts of the body.
10
The
preceding patterns do not reflect delayed luminescence.
Such is excluded as in previous studies by sufficient adap-
tation to dark room conditions prior to measurements.
4,9
Ultra-weak photon emission in the optical spectrum is
generally thought to reflect random imperfections accom-
panying the normal physiologic processes of oxygen con-
sumption as well as the destructive activity of reactive oxy-
gen species.
6–8,19,20
Historically, spectral analysis of human
photon emission provided some initial information about the
phenomenon.
1,2,4,9
The wavelengths of emission were cap-
T
ABLE
1. A
VERAGE
I
NTENSITY OF
E
ACH OF THE
12 S
PECIFIC
A
NATOMIC
L
OCATIONS FOR THE
G
ROUP OF
10 T
RANSCENDENTAL
M
EDITATION
™P
RACTITIONERS AND FOR THE
G
ROUP OF
C
ONTROL
S
UBJECTS
Photo counts (cps)
Controls TM practitioners p-Value
Anatomic location (mean SEM) (mean SEM) (Wilcoxon test)
Torso
Abdomen—right 5.27 0.59 3.54 0.54 ns
Abdomen—left 5.26 0.71 3.99 0.84 ns
Solar plexus 6.18 0.70 3.62 0.23 0.02
Heart 8.33 1.52 4.55 0.30 0.007
Head
Throat 12.02 1.72 5.75 0.60 0.004
Cheek—right 12.27 1.68 7.71 1.18 0.04
Cheek—left 12.67 1.73 7.96 0.99 ns
Forehead 11.82 1.78 6.58 0.74 0.02
Hand
Hand palm—right 13.12 2.16 11.03 0.58 ns
Hand palm—left 12.56 2.15 9.72 0.68 ns
Hand dorsal—right 10.36 2.82 6.53 0.97 ns
Hand dorsal—left 9.51 3.00 6.48 0.51 ns
Total 119.36 17.26 77.48 5.71 0.03
Groups were compared by nonparametric two-sample Wilcoxon test. ns not significant.
T
ABLE
2. C
ONTRIBUTION OF
E
ACH
A
NATOMIC
L
OCATION TO
T
OTAL
E
MISSION FOR THE
G
ROUP OF
10 T
RANCENDENTAL
M
EDITATION
™P
RACTITIONERS AND FOR THE
G
ROUP OF
C
ONTROL
S
UBJECTS
Control group TM practitioners
% contribution % contribution p-Value
Anatomic location (mean SEM) (mean SEM) (Wilcoxon test)
Abdomen—right 4.87 0.72 4.44 0.51 ns
Abdomen—left 4.57 0.44 5.02 0.87 ns
Solar plexus 5.56 0.59 4.78 0.29 ns
Heart 6.92 0.38 6.03 0.42 ns
Throat 10.36 0.88 7.38 0.48 0.02
Cheek—right 10.57 0.85 9.67 0.82 ns
Cheek—left 10.96 1.12 10.11 0.58 ns
Forehead 10.36 1.31 8.42 0.54 ns
Hand palm—right 10.73 0.93 14.54 0.77 0.003
Hand palm—left 10.22 0.90 12.61 0.92 0.05
Hand dorsal—right 7.84 0.94 8.44 0.59 ns
Hand dorsal—left 7.04 1.04 8.56 0.73 ns
Groups were compared by nonparametric two-sample Wilcoxon test.
ns not significant.
PHOTON EMISSION IN TM PRACTITIONERS AND CONTROLS
37
tured by photomultipliers in the late 1970s and 1980s ad-
dressing different organ systems,
21–25
blood,
25–29
hepatic
microsomal fractions,
30,31
enzymatic reactions and bio-
chemical processes involving free radicals,
32–36
and lipid
peroxidation.
25,30,37,38
Such data demonstrated that human ultra-weak photon
emission in the visible range corresponds to those emission
bands (480, 520, and 575 nm) previously reported for ultra-
weak photon emission of systems undergoing lipid peroxi-
dation and the production of
1
O
2
paired molecules.
Several lines of evidence have suggested that the lower
emission values from TM practitioners are connected to a
lower level of stress. Stress is connected to increased produc-
tion of reactive oxygen species and related chemical reactions
resulting in cell and tissue damage.
8,39
Schneider et al.
16
re-
ported preliminary findings suggesting that lower peroxide lev-
els are associated with the use of TM. Altogether, it can be
hypothesized that a persistent program of TM meditation might
well change the oxidative status of the human body. In the
present study long-term TM practitioners participated, some
of whom practiced additionally the more advanced TM-Sidhi
program. Future studies are aimed to relate photon emission
intensity and years of experience with TM and the Sidhi pro-
gram. Also, it needs to be established whether these findings
are the case for other meditation techniques.
A few other physiologic conditions that influence levels
of oxidative damage must be taken into account.
9
It is in-
teresting to note that caloric restriction, which decreases the
rate of aging, also decreases oxidative damage.
40–42
The lev-
els of oxidative damage generally increase with age. In the
present study, the lower emission of TM practitioners as
compared to control subjects could not be ascribed to age
differences because both groups have similar mean age and
no correlation could be observed by plotting age against pho-
ton emission. One cannot exclude that differences in inten-
sity, at least in part, result from differences in dietary habits.
Further research is needed to clarify such issues.
ACKNOWLEDGMENTS
This work was supported by an independent research
grant from the Samueli Institute of Information Biology and
the Rockefeller-Samueli Center for Research in Mind-Body
Energy. The authors state that there is no conflict of inter-
est. They are not TM practitioners. In this regard, they thank
G.J. Gerritsma and J. Segaar for their advice. The authors
thank Fritz-Albert Popp and Yu Yan for their support, and
John Ackerman for editing the text.
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Address reprint requests to:
Roeland Van Wijk, Ph.D.
Faculty of Biology
Utrecht University
Padualaan 8, 3584 CH, Utrecht
The Netherlands
E-mail: meluna.wijk@wxs.nl
VAN WIJK ET AL.
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