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Enhancing Vigilance by Low Intensity Transcranial Pulsed Magnetic Stimulation Applying the Entrainment Model

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  • BION Institute

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Vigilance and attention are very important aspects of our working capacities and our general wellbeing as well. Besides taking drugs, they can in principle be achieved also by an appropriate transcranial pulsed magnetic field (MF) stimulation. In the reported research, we took the entrainment principle as the leading one, trying to enhance high beta waves with volunteers. The research conformed to clinical testing conditions. We checked the volunteers’ state monitoring their physiological parameters, their respons-es following visual analog scale (VAS) method and their performance with the Clock test of sustained attention. In addition to observing the differences between the true stimulation and the sham one, we checked also the psychological influence on atten-tion (additional to true stimulation). The results demonstrated overall enhanced relax-ation with MF stimulation that was further improved by expectation. Relaxation, bet-ter nervous energy conservation and better performance (reduction of errors) may be concluded from all parts of the research.
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Open Access Library Journal
2019, Volume 6, e5782
ISSN Online: 2333-9721
ISSN Print: 2333-9705
DOI:
10.4236/oalib.1105782 Oct. 17, 2019 1
Open Access Library Journal
Enhancing Vigilance by Low Intensity
Transcranial Pulsed Magnetic Stimulation
Applying the Entrainment Model
Igor Jerman*, Primož Dovč, Petra Ratajc
Physiological Testing Department, BION, Institute for Bioelectromagnetics and New Biology, Ljubljana, Slovenia
Abstract
Vigilance and attention are very important aspects of our working capacities
and our general wellbeing as well. Besides taking drugs, they can in principle
be achieved also by an appropriate
transcranial pulsed magnetic field (MF)
stimulation. In the reported research, we took the entrainment principle as
the leading one, trying to enhance high beta waves with volunteers. The re-
search conformed to clinical testing conditions. We checked the vo
lunteers’
state monitoring their physiolo
gical parameters, their responses following
visual analog scale (VAS) method and their performance with the Clock test
of sustained attention. In addition to observing
the differences between the
true stimulation and the sham one, we checked also the psychological influ-
ence on attention (additional to true stimula
tion). The results demonstrated
overall enhanced relaxation with MF stimulation that was further improved by
expectation. Relaxation, better nervous energy conservation and better perfor-
mance (reduction of errors) may be concluded from all parts of the research.
Subject Areas
Bioelectromagnetics or Bioengineering
Keywords
Magnetic Field Stimulation, Low Intensity rTMS, PEMF, Attention, Relaxation
,
Conditions of Clinical Trials, Electrophysiological Parameters, Visual Analog
Scale (VAS), Clock Test
1. Introduction
1.1. State of the Art
Vigilance and attention are very important aspects of our working capacities and
How to cite this paper:
Jerman, I.,
Dovč,
P
. and Ratajc, P. (2019)
Enhancing
Vigilance by Low Intensity Transcranial
Pulsed Magnetic Stimulation Applying the
Entrainment Model
.
Open Access Library
Journal
,
6
: e5782.
https://doi.org/10.4236/oalib.1105782
Received:
September 12, 2019
Accepted:
October 14, 2019
Published:
October 17, 2019
Copyright © 201
9 by author(s) and Open
Access Library Inc
.
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I. Jerman et al.
DOI:
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our general wellbeing as well. One possibility to achieve high vigilance is by tak-
ing drugs like caffeine, guaranine or cocaine or by having a very good, deep and
sufficiently long sleep. However, applying drugs eventually brings undesirable
side effects and a need for progressive raising the dose. On the other hand, a
constant deep sleep is a rare commodity in our modern stressful way of life. For
these reasons, it is very important to look for alternative means to achieve better
vigilance and attention, which should be noninvasive, thereby provoking no
harmful side effects. One such possibility is an application of a pulsed magnetic
stimulation (PEMF) in the region of the head, which can be classified also as a
low-intensity rTMS.
Magnetic stimulation of the head region usually utilizes relatively high inten-
sities of magnetic fields of low frequencies and may have multiple healing effects,
especially with psychiatric and neurologic disorders [1]. The theoretical back-
ground of high-intensity rTMS is based on the magnetic induction of electric
fields in the brain region that may excite nervous cells and evoke action poten-
tials or may work inhibitory [2]. Therefore, this kind of MF treatment is invasive
to the brain and may bring even harmful side effects like seizures [3]. To turn to
another, perhaps a little less effective, but a still promising method of low-intensity
rTMS or PEMF stimulation is, therefore, a rational option. Low-intensity mag-
netic fields cannot elicit nerve cell excitation; neither do they have thermal ef-
fects. From the standpoint of mainstream physics, they should not have any
measurable biological effects. It is therefore understandable that the mechanism
of their effects is still an object of scientific debate and of developing various
theoretical models. Some of the latter have also empirical confirmations, yet no
one has been universally recognized (see also [4] and [5]). Non-thermic and low
induction effects should function on the principle of resonance with some phy-
siological and biochemical processes in the body. If applied to the head, they
should influence neuronal excitation patterns and the brainwaves. Since the
brainwaves represent a long-range coherent mode of brain cells excitation [6],
the applied MF most probably work through resonance. Most probably, they in-
terfere with the endogenous electromagnetic and dipolar oscillations within cells
and among them (for a more comprehensive study see [7]).
From the standpoint of general principles of life, the interference with physi-
ological processes may bring two opposing results: 1) enhancing, based on the
principle of resonance and 2) inhibitory, because the homeostatic mechanisms
of organism’s physiology tend to oppose an intrusive external influence. The lat-
ter may be similar to radiation hormesis [8], where a small dose of ionizing radi-
ation brings a stimulation of growth, which is in opposition to the effects of the
same radiation at higher doses. In connection to this, it is interesting and signif-
icant that various authors found both kinds of effects following the MF stimula-
tion of the head region.
The (stimulating) resonance effect is known as entrainment and is frequently
expected as a consequence of the MF stimulation of the head region, although
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other stimulation means may be applied, like light and sound [9]. Bell
et al
. [10]
published one of the first reports of the entrainment effect provoked by a sinu-
soidal MF. They found a non-linear enhancing relation between stimulation and
the EEG response, corroborating the entrainment hypothesis. Another, more
comprehensive study by Cvetkovic and Cosic [11] comprising four different
stimulating frequencies showed that it is possible to influence the alpha and beta
waves in stimulated volunteers. However, the effect was not direct under all sti-
mulation conditions and could be even reverse, which corroborates the homeos-
tatic response (inhibition). There are further positive reports regarding the en-
trainment principle, like the profound study of Thut
et al
. [12] [13], nevertheless
there are also reports that contradict this effect [12] [14] [15]. Cook
et al
. [16]
published a study that tried to find some explanation for these controversies.
They found that previous exposure to a pulsed MF sequence determined sub-
jects’ responses in the experiment (see also [17]).
When we come to a possibility of influencing vigilance (attention), we may
assume an incidental magnetic stimulation will enhance the proportion of
brainwaves that are in approximate resonance with the stimulating MF. Howev-
er, as some researches demonstrate, the entrainment influence may not neces-
sarily comprise only the direct resonant frequency but may entail also its sub-
harmonics and higher harmonics. An interesting study was performed by
Ghione and colleagues [18] regarding the effects of 90-min exposure to a homo-
genous 50 Hz ELF MF at a flux density of 40 or 80 µT applied to the head region.
While one would expect an enhancement of high-frequency brainwave bands
(gamma, beta), they report a considerable increase in alpha activity after 80 µT
magnetic treatment compared to the sham exposure. This indicates that here,
entrainment followed subharmonics of the stimulating frequency that was ap-
proximately two octaves and a half higher than the influenced alpha waves. On
the other hand, Gao
et al
. [19] report an influence that may be ascribed to higher
harmonics of the applied PEMF frequency. Here, the influence of ELF PEMF
with the frequency of 1 Hz (intensity: 10 mT, stimulation duration: 20 min.) on
the human brain was conducted. In comparison with the sham exposure group,
the EEG power of theta band (3.5 - 7.5 Hz) and lower-alpha band (7.5 - 10 Hz)
of the stimulation group increased significantly after magnetic stimulation. In
direct entrainment, one would expect the stimulation of delta waves (0 - 3.5 Hz),
yet approximately the second (4 Hz) and the third (8 Hz) octaves involving
brainwaves were stimulated.
Regarding the MF stimulation of vigilance and attention, not much research
has yet been performed. Some researches concentrated on the direct electric
current transcranial stimulation and found that it could be a useful fatigue
countermeasure and may be more beneficial than caffeine since boosts in per-
formance and mood last longer time [20]. Other authors used sophisticated
means to stimulate the spine by using a static magnetic field with a spatial alter-
nation of poles that prevented drowsiness without invoking the REM rebound
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phenomenon [21]. The latter, however, appeared with many other methods of
stimulating vigilance and attention. Stimulation of attention was found also with
a high intensity extremely low frequency (1 Hz) rTMS applied to autistic pa-
tients [22]. They found a significant error omission rate after rTMS stimulation.
On the other side of the intensity spectrum, we can find a report of a case study,
in which an applied MF of only 7.5 pT intensity, 4 Hz frequency, and sinusoidal
form significantly increased the mental capacities of a multiple sclerosis patient
[23].
1.2. Background of Present Research, Intentions and
Assumptions
In seeking the best possibility to enhance performance in the sense of higher vi-
gilance and attention, we found that in such psychological states a high frequen-
cy in the high beta frequency band increased [24]. In addition to EEG measure-
ments, where we expected the brainwaves would follow the entrainment model,
it was our interest to check the influence of MF stimulation also on other physi-
ological states, performance capacities and self-perception of volunteers. For the
leading frequency the one close to the border between beta and gamma waves
(25 - 42 Hz) was chosen according to findings published in Lutz
et al
. [24] and
Rubik [25]. The final (exact) determination of the leading frequency followed
the so-called GM-scale, found by Meijer and Geesink after a comprehensive
study of bioelectromagnetic articles with either stimulatory or inhibitory effects
[26]. A supportive frequency of a lesser intensity was chosen as a frequency of
water [27] because our organisms are mainly composed of water. This frequency
is at the same time in harmonic relationship with the leading frequency (its ma-
jor sixth) and is close to the gamma/high beta brainwaves. During MF stimula-
tion of volunteers our expectation (research assumption) was as follows:
brainwaves: enhancing the proportion of beta waves during stimulation, les-
sening at least one of the three other brainwaves bands (alpha, theta, delta);
general electrophysiological parameters: calming vegetative nervous system
due to rhythmic MF pulsations;
tendency to sleep: should be lessened due to assumed enhanced vigilance;
higher accuracy of performance, lower error rate and shorter reaction time
with the Clock test of sustained attention
In the research we wanted to check also the influence of expectation in com-
bination with MF stimulation on all three above listed groups of parameters, so
in addition to the sham-exposed volunteers (control) and the stimulated ones
(verum), we examined parameters of volunteers who a) were stimulated, b)
knew that they were stimulated and c) were told what should they expect from
the stimulationthe informed situation. Our hypothesis here was that the in-
tentionally provoked expectations in the anticipated direction (higher vigilance)
would enhance the influence of MF stimulation.
Although the majority of research in bioelectromagnetics is performed by us-
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ing a homogenous MF, such field is only very rarely applied in practical situa-
tions where an MF stimulation may have some practical or therapeutic use.
Namely, devices producing highly non-homogenous MFs are mostly offered on
the market, which shaped our decision to apply a highly inhomogeneous field to
volunteers. The MF was produced by five different coils arranged around the
head (see Figure 1). The measures of a coil were as follows 26.5 mm (length) ×
20 mm (width) × 5.1 mm (thickness).
2. Material and Methods
2.1. General Data
2.1.1. Tested Groups
The research was performed in May 2019 in the laboratories of the Institute for
Bioelectromagnetics and New Biology (BION Institute) in Ljubljana, Slovenia,
EU. In the research, 25 volunteers aged from 29 to 76 years (13 men and 12
women) were chosen. The selection criterion was that they had to be disciplined
and that they do not suffer from some serious illness, either chronic or acute.
They were subject to three different experimental situations:
1) sham stimulation (Control situation);
2) true stimulation (Verum situation);
3) informed true stimulation as explained in the Introduction (Informed situ-
ation).
The first two groups were treated in conformity with the clinical trials condi-
tions:
Prospectiveness (general criteria for the effectiveness of the device’s activity
were determined in advance);
Placebo effect ruled out (volunteers did not know whether they were stimu-
lated or not);
Double blind (neither the volunteer nor the research assistant knew whether
MF stimulation was applied or not);
Randomized (the decisions about sham or true exposure were made ran-
domly).
The volunteers in the Informed situation were intentionally informed about
the stimulation; this situation was always applied after the Control and the Ve-
rum situations, since the volunteers were the same in all three groups.
The volunteers signed an informed consent in which they agree to cooperate
as subjects in this non-invasive scientific research in bioelectromagnetics.
2.1.2. Stimulating Magnetic Field Characteristics and Positions
We applied MF stimulation in the region of the head as presented on Figure 1
and described in Table 1. The device generating the MF was manufactured by
MDCN Technologies Inc. New York, USA (Omnipemf device) and will be
named the device.
During the research, we constantly measured the environmental EM fields
and found no significant variation in the frequency range from 5 Hz to 2 GHz
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Figure 1. The experimental situationa volunteer with attached electrodes needed for
the measurements of physiological parameters and with the stimulating device in place.
Simultaneously she performs the Clock test.
Table 1. Parameters of MF stimulation.
Frequency
(Hz)
Magnetic field
intensity (B)
Location Role
33.71 2.5 mT frontal (1 coil)
54 0.25 mT
frontal (1 coil), temporal lobes left
(2 coils) and right (2 coils)
supportive stimulation
between different days. The geomagnetic field varied from 47,963 to 48,002 nT
(data from the nearest INTERMAGNET [28] observatory located in Lonjsko
polje, Croatia).
2.2. Physiological Testing and Exposure Procedure
Each volunteer attended the measurements thrice at the same hour of the day.
At the arrival, he/she filled out the questionnaire and completed the visual ana-
log scale (VAS) test (see 2.4. for more detail). After that research assistant placed
the device on his/her head in an appropriate position (Figure 1) and attached
the electrodes needed for the measurements of physiological parameters. All the
preparations before the measurements took about 10 minutes and during this time
the device was already stimulating volunteers. This 10 minutes pre-treatment was
intended to extend the stimulation period to about 40 minutes in total. During
the measurements, which lasted for 30 minutes, volunteers sat in a wooden chair
in front of a computer and were doing the modified Clock test from the PEBL
Psychological Test Battery [29]. This test is a computerized version of the
Mackworth Clock device [30] and is used in the field of experimental psychology
to study the effects of long-term vigilance on the detection of signals. The test
took approximately 30 minutes to complete. During this time, volunteers had to
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react with the space key on a keyboard when dark dot skipped one position on a
circular orbit. For the test to be as monotone and tedious as possible, skips hap-
pened only in approximately 0.8% of total dot shifts. The following parameters were
measured during this time: brain wave activity (EEG) in four standard frequency
spectra (beta waves from 14 to 30 Hz, alpha waves from 8 to 14 Hz, theta waves
from 4 to 8 Hz and delta waves from 0 to 4 Hz), skin conductance, heart rate, res-
piration rate, finger temperature, heart rate variability and thorax expansion depth.
The positive electrode for the EEG measurement was placed on the F3 position of
the international 10 - 20 EEG system [31], while the negative and ground electrodes
were placed on the right and the left earlobe, respectively. After the removal of the
electrodes, the volunteer again completed the VAS test and the questionnaire
enabling the comparison between before and after for each tested situation.
We calculated thirty-second medians for every volunteer. On the basis of
these data, we calculated aggregated thirty-second medians for all 25 volunteers
and used this data to draw graphs for each measured parameter and for further
statistical analysis. For the sake of analysis and interpretation of the results, 30
minutes of measurements were split into three parts (each consisting of 20 data
points with calculated 30-second median):
first partfrom 0 to 10 minutes,
second partfrom 10 to 20 minutes,
third partfrom 20 to 30 minutes.
For calculating statistically significant differences between any of the three
experimental situations we used the Friedman test. With a post-hoc test (Wilcoxon
Signed-Rank test) we determined which comparison demonstrated these differenc-
es. The outcome of the results for all tests was corrected by the Holm-Bonferroni
correction for multiple comparisons [32].
2.3. Clock Test of Sustained Attention
A total of 4500 dot shifts occurred in a Clock test in 30 minutes out of which
there were approximately 36 dot skips (0.8%). Because the number of skips ran-
domly varied between volunteers, we calculated the proportion of correctly de-
tected skips out of all skips (CSoS). A number of errors were recorded if a vo-
lunteer reacted when there was no skip, from which the proportion of error res-
ponses out of total dot shifts was calculated (FRoA). Additionally, correct res-
ponses out of all dot shifts were calculated (CRoA). Two kinds of responses were
evaluated as correct: 1) response when there was a skip and 2) no response when
there was no skip (only shift), see Figure 2 for better understanding. Reaction
time was recorded between the moment a skip happened and the moment a vo-
lunteer reacted to it (RT).
We used the Friedman test to figure out whether there were any statistically
significant differences. Additionally, we conducted post hoc tests (Wilcoxon
Signed-Rank Test) to determine exactly between which two situations significant
differences demonstrated themselves.
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Figure 2. A screenshot of the Clock test of sustained attention. An explanation of a dot
skip and a dot shift is labeled for a better notion of the test.
2.4. The Visual Analogue Scale (VAS)
The Visual Analogue Scale (VAS) has been in use for the measurement of sub-
jective parameters that are impossible to measure by any physical method, like
pain, anxiety, quality of sleep, etc. since the 1920s [33]. Today it can be used in-
dependently or as a supplement to other measurements and may be used even in
pharmacology [34]. The scale consists of a line that is usually 100 mm in length.
On each side, there is an anchor descriptor such as very unrelaxedvery re-
laxed. The volunteer makes a mark on this (normally and in our case horizontal)
line, reflecting his/her perception. Afterward, the distance from the left endpoint
to the mark is measured in mm. In our case, the VAS line was displayed on the
computer screen and the volunteer had to mark the position between the de-
scriptors by using a mouse and clicking the determined point. VAS measure-
ments enable a consequent statistical analysis of data as in any technical de-
vice-based measurement systems.
We used VAS scale for evaluation of the subjective perception of three differ-
ent parameters: relaxation, concentration and energy level. VAS scale was in-
cluded in online survey volunteers completed before and after each measure-
ment. The online open-source application for web surveys [35] determined the
marked position as a distance from the left point in millimeters (range 0 - 100),
which was considered as the VAS score. We determined mean VAS scores ob-
tained before and after each measurement, and compared them using t-test. We
calculated a change of VAS scores for each individual person (after-before the
individual measurement), and used paired t-test for the comparisons of different
situations (Control, Verum, Informed).
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Measurements were carried out in a double-blind and randomized fashion, fol-
lowing the same conditions for clinical testing as described in section 2.1.1 (Table 2).
Besides VAS testing, a question as to when a volunteer expected to be under
the true stimulation as well as when they felt more focused was asked after the
second testing.
3. Results
3.1. Physiological Testing
Results concerning electrophysiological measurements demonstrate statistically
significant differences between three experimental situations for the following
parameters: skin conductance, heart rate, finger temperature, the proportion of
alpha and delta waves and thorax expansion depth (Table 3, Wilcoxon signed-
rank test). Skin conductance, heart rate, and finger temperature demonstrated
differences in all three parts of measurements.
SC was substantially lower for both the Verum and the Informed situations
Table 2. Questions and anchor descriptors for evaluation of three different parameters.
Parameter Question Anchor descriptors
Relaxation
How relaxed do you feel at the moment?
Very unrelaxedvery relaxed
Concentration
How focused do you feel at the moment?
Very unfocused—very focused
Energy level
How full of energy do you feel at the
moment?
Complete lack of energyfull of
energy
Table 3. p-values of the Friedman test based on 30-second medians for each parameter
during the three parts of measurements. Holm-Bonferroni correction for multiple com-
parisons is applied to the p-values in the table. Bold values denote statistically significant
differences between at least two of the three different experimental situations (p < 0.05),
values with regular black font represent statistically marginally significant differences
between at least two of the three different experimental situations (p < 0.1). Marks:
SCskin conductance, RRrespiration rate, HRheart rate, TMPfinger temperature,
beta, alpha, theta, and deltathe proportion of beta, alpha, theta and delta spectrum of
brain activity, HRV—heart rate variability, TEDthorax expansion depth.
0 - 10 min
10 - 20 min
20 - 30 min
SC
0.000
0.000
0.000
RR
0.578
0.159
0.521
HR
0.004
0.011
0.002
TMP
0.000
0.000
0.000
beta
1.000
0.668
0.668
alfa
0.003
0.668
0.668
theta
0.011
0.210
0.210
delta
0.002
0.007
0.007
HRV
1.000
0.668
0.668
TED
0.000
0.268
1.000
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during the entire measurements when compared to the Control one (Figure 3).
Lower SC indicates deeper relaxation of volunteers [36]. However, SC indicates
that expectation additionally lowered its values in the Informed situation when
compared to the Verum one (a significant difference in the first part of mea-
surements). There were also substantial differences in initial values for this pa-
rameter because volunteers have already been stimulated for 10 minutes before
the start of measurements (Table 4).
Figure 3. Skin conductance (SC) from twenty-five volunteers (Verum, Informed and Control situations). Asterisks
denote statistically significant differences (**p < 0.01) in three parts of measurements separated by vertical grey
lines. Green asterisks: differences between Verum and Control, orange asterisks: differences between Informed and
Control. Statistical differences for comparison between Verum and Informed situations are not shown.
Table 4. p-values of the post-hoc test (Wilcoxon Signed-Rank Test) based on 30-second medians for each parameter during the
three parts of measurements. Holm-Bonferroni correction for multiple comparisons is applied to the p-values in the table. Values
with bold black font represent statistically significant differences between two of the selected situations (p < 0.05), values with
regular black font represent statistically marginally significant differences between two of the selected situations (p < 0.1). Marks:
SCskin conductance, RRrespiration rate, HRheart rate, TMPfinger temperature, beta, alpha, theta and deltathe pro-
portion of beta, alpha, theta, and delta spectrum of brain activity, HRVheart rate variability, TEDthorax expansion depth.
Comparison
pair
0 - 10 min
10 - 20 min
20 - 30 min
Verum
Control
Informed
Control
Verum
Informed
Verum
Control
Informed
Control
Verum
Informed
Verum
Control
Informed
Control
Verum
Informed
SC
0.008
0.008
0.008
0.008
0.008
1.000
0.008
0.008
0.008
RR
1.000
1.000
1.000
1.000
1.000
0.060
1.000
1.000
1.000
HR
0.278
0.016
0.373
0.054
0.024
1.000
0.011
0.197
0.908
TMP
0.178
0.008
0.373
0.008
0.008
1.000
0.111
0.008
0.008
beta
1.000
1.000
1.000
1.000
0.646
1.000
1.000
1.000
1.000
alpha
0.087
0.054
1.000
0.606
0.373
1.000
0.019
0.840
1.000
theta
0.278
1.000
0.124
1.000
1.000
1.000
0.530
0.606
1.000
delta
1.000
0.042
0.278
0.395
0.024
0.701
1.000
1.000
0.530
HRV
1.000
1.000
1.000
1.000
1.000
1.000
1.000
1.000
1.000
TED
0.008
0.011
0.530
0.395
0.556
1.000
1.000
1.000
1.000
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TED demonstrated significant differences only in the first part of the mea-
surements where values for the Control situation were higher as compared to
both the Verum and the Informed situations (Figure 4). After 13 minutes this
parameter suddenly dropped for the Control situation, after which there were no
differences between the three situations. Lower TED is correlated with a lower
concentration of adrenaline (within physiological concentrations; see [37]),
which is one of the stress hormones and stimulator of the sympathetic nervous
system. This result is therefore in harmony with SC results.
HR was lower for both the Verum and the Informed situations in comparison
to the Control one at least during one part of the measurements (Figure 5). The
Figure 4. Relative thorax expansion difference (TED) from twenty-five volunteers (Verum, Informed and Control
situations). Asterisks denote statistically significant differences (*p < 0.05; **p < 0.01) in three parts of measure-
ments separated by vertical grey lines. Green asterisks: differences between Verum and Control, orange asterisks:
differences between Informed and Control. Statistical differences for comparison between Verum and Informed
situations are not shown.
Figure 5. Heart rate (HR) from twenty-five volunteers (Verum, Informed and Control situations). Asterisks de-
note statistically significant differences (*p < 0.05) in three parts of measurements separated by vertical grey lines.
Green asterisks: differences between Verum and Control, orange asterisks: differences between Informed and
Control. Statistical differences for comparison between Verum and Informed situations are not shown.
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Verum situation demonstrated significant differences in the third part of the
measurements, while the Informed one demonstrated them in the first two parts.
In general, both the Verum and the Informed situations showed a lower HR
than the Control one which indicates a greater calmness and relaxation and
which is again in accordance with both SC and TED.
TMP was significantly higher in both the Verum and the Informed situations
when compared to the Control one; the Informed situation yielded even slightly
higher values than the Verum one (Figure 6). Expectations for the Informed
situation intensified the device’s influence on TMP. A lower TMP was found to
correlate with stress exposure [38]. Therefore, we may safely assume that a high-
er peripheral temperature corresponds to a more relaxed state.
The proportion of alpha waves was statistically significantly higher only in the
last part of measurements for the Verum situation when compared to the Con-
trol one (Figure 7). Higher alpha waves for the Verum situation indicate a
slightly increased relaxation. Even if there is only a slight difference in alpha
waves between the three experimental situations there is a prominent difference
in linear trends. It is slightly positive for both the Verum and the Informed situ-
ations while it is negative for the Control situation. This speaks about increasing
relaxation for both MF stimulated situations.
The proportion of delta waves was significantly higher in the first two parts of
measurements in the Informed situation when compared to the Control one
(Figure 8). The linear trend for both the Verum and the Informed situations was
slightly negative while it was slightly positive for the Control situation. We ascribe
the difference in the first part to a higher overall relaxation as shown by many other
parameters, while the negative trend may be a consequence of the expected (gra-
dual) entrainment, where there should be a relative diminution of low-frequency
brain waves. There was no difference in beta waves, as seen on Figure 9.
Figure 6. Finger temperature (TMP) from twenty-five volunteers (Verum, Informed and Control situations). As-
terisks denote statistically significant differences (*p< 0.05; **p< 0.01) in three parts of measurements separated by
vertical grey lines. Green asterisks: differences between Verum and Control, orange asterisks: differences between
Informed and Control. Statistical differences for comparison between Verum and Informed situations are not
shown.
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Figure 7. Proportion of alpha waves from twenty-five volunteers (Verum, Informed and Control situations). Aste-
risks denote statistically significant differences (*p < 0.05) in three parts of measurements separated by vertical
grey lines. Green asterisk: the difference between Verum and Control. Statistical differences for comparison be-
tween Verum and Informed situations are not shown.
Figure 8. Proportion of delta waves from twenty-five volunteers (Verum, Informed and Control situations). Aste-
risks denote statistically significant differences (*p < 0.05) in three parts of measurements separated by vertical
grey lines. Orange asterisks: differences between Informed and Control. Statistical differences for comparison be-
tween Verum and Informed situations are not shown.
Mean values with standard error of measured parameters for all three situa-
tions and for all three parts of measurement are presented in Table 5.
3.2. Clock Test of Sustained Attention
Statistical analysis demonstrated a significant difference between the Informed
and the Control situation for the proportion of error responses out of total dot
shifts (FRoA, Table 7). Although the Friedman test demonstrated significant
differences for mean reaction time too (Table 6), there was no difference in the
post-hoc test for the comparison of three situations (Table 7), nevertheless, from
the results, we may assume that the Informed situation enhanced this parameter
vs. the other two ones.
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Figure 9. Proportion of beta waves from twenty-five volunteers (Verum, Informed and Control situations).
Table 5. Overview of the mean values for all measured parameters with ± standard error (N = 20) for all three test situations.
Marks: SCskin conductance, RRrespiration rate, HRheart rate, TMPfinger temperature, beta, alpha, theta, and deltathe
proportion of beta, alpha, theta and delta spectrum of brain activity, HRVheart rate variability, TEDthorax expansion depth.
0 - 10 min 10 - 20 min 20 - 30 min
Verum Informed Control Verum Informed Control Verum Informed Control
SC 16.732 ± 0.145 14.251 ± 0.372 20.63 ± 0.217 15.129 ± 0.233 14.528 ± 0.26 20.131 ± 0.086 14.704 ± 0.153 12.157 ± 0.163 20.175 ± 0.186
RR 17.688 ± 0.108 17.239 ± 0.121 17.552 ± 0.155 17.098 ± 0.094 16.511 ± 0.172 17.183 ± 0.121 16.615 ± 0.121 16.176 ± 0.175 16.704 ± 0.173
HR 72.012 ± 0.186 70.778 ± 0.296 73.13 ± 0.248 71.691 ± 0.176 71.668 ± 0.277 73.639 ± 0.317 70.263 ± 0.228 71.39 ± 0.314 72.916 ± 0.342
TMP 34.781 ± 0.084 34.959 ± 0.041 34.447 ± 0.046 35.03 ± 0.031 35.078 ± 0.018 34.583 ± 0.032 34.851 ± 0.02 35.035 ± 0.022 34.735 ± 0.019
beta 25.607 ± 0.326 25.644 ± 0.324 25.585 ± 0.324 26.797 ± 0.344 26.74 ± 0.343 27.01 ± 0.357 25.396 ± 0.587 25.314 ± 0.565 25.316 ± 0.57
alpha 21.267 ± 0.306 21.306 ± 0.303 21.397 ± 0.295 20.694 ± 0.271 20.804 ± 0.275 20.925 ± 0.245 19.53 ± 0.25 19.583 ± 0.25 19.495 ± 0.219
theta 23.052 ± 0.149 23.07 ± 0.15 23.184 ± 0.15 23.283 ± 0.173 23.304 ± 0.173 23.262 ± 0.176 24.435 ± 0.256 24.489 ± 0.242 24.432 ± 0.24
delta 30.073 ± 0.321 29.98 ± 0.31 29.834 ± 0.297 29.226 ± 0.344 29.152 ± 0.345 28.802 ± 0.254 30.639 ± 0.346 30.614 ± 0.339 30.756 ± 0.313
HRV 10.808 ± 0.436 10.844 ± 0.348 11.57 ± 0.56 12.889 ± 0.373 12.42 ± 0.372 11.826 ± 0.4 12.594 ± 0.68 12.075 ± 0.499 13.431 ± 0.488
TED 2.678 ± 0.043 2.51 ± 0.045 3.681 ± 0.108 2.828 ± 0.08 2.797 ± 0.124 3.33 ± 0.139 3.05 ± 0.109 2.92 ± 0.157 2.919 ± 0.104
Table 6. p-values of Friedman based on averages of 25 volunteers for different parameters. Holm-Bonferroni correction for mul-
tiple comparisons is applied to the p-values in the table. Bold values denote statistically significant differences between at least two
of the three different experimental situations (p < 0.05). Marks: CSoSa proportion of correctly detected skips out of total skips,
FRoA—a proportion of error responses out of total shifts, CRoA—a proportion of correctly detected skips out of total shifts,
RT—mean reaction time.
Parameter
p-value
CSoS
0.782
FRoA
0.013
CRoA
0.782
RT
0.034
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The proportion of error halved from around 0.13% in the Control situation to
around 0.06% in the Informed one (Figure 10). This parafmeter decreased to about
0.08% in the Verum situation, which is very close to the Informed one but still not
enough for the statistically significant difference when compared to the Control one.
Although the reaction time did not demonstrate a statistically significant dif-
ference between different experimental situations the average for the Informed
situation was still much lower than for the other two situations (around 570 ms
while it was around 610 ms for the Control and the Verum situations; Figure 11).
Mean values with standard error for all measured parameters and for all three
situations are presented in Table 8.
3.3. Visual Analog Scale (VAS)
After surveying all VAS measurements we estimated that only the scores from 21
Table 7. p-values of the post-hoc test (Wilcoxon signed-rank test) based on averages of
25 volunteers for different parameters. Holm-Bonferroni correction for multiple compar-
isons is applied to the p-values in the table. Bold values denote statistically significant dif-
ferences between at least two of the three different experimental situations (p < 0.05).
Marks: CSoSproportion of correctly detected skips of total skips, FRoA—proportion of
error responses of total dot shifts, CRoA—proportion of correctly detected skips of total
shifts, RTmean reaction time.
Comparison pair
Verum Control
Informed Control
Verum Informed
CSoS
1.000
1.000
1.000
FRoA
1.000
0.016
1.000
CRoA
1.000
1.000
1.000
RT
1.000
0.131
0.230
Figure 10. Proportion of error responses of total dot shifts ± SE (N = 25) in Clock test for
the Verum, Informed and the Control situations. The asterisk denote statistically the sig-
nificant difference (*p < 0.05) between Informed and Control.
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Figure 11. Mean reaction time ± SE (N = 25) in Clock test for the Verum, Informed and
the Control situations.
Table 8. Overview of the mean values for all measured parameters with ±standard error
(N = 20) for all three test situations. Marks: CSoSproportion of correctly detected skips
of total skips, FRoAproportion of error responses of total dot shifts, CRoAproportion
of correctly detected skips of total shifts, RT—mean reaction time.
CSoS [%]
FRoA [%]
CRoA [%]
RT [ms]
Verum
81.337 ± 3.263
0.076 ± 0.023
99.759 ± 0.044
609.22 ± 26.376
Informed
81.997 ± 3.807
0.06 ± 0.027
99.774 ± 0.048
568.575 ± 26.056
Control
83.228 ± 2.909
0.126 ± 0.044
99.739 ± 0.053
606.413 ± 24.14
volunteers were suitable for analysis. Results from four volunteers were excluded
due to high initial VAS scores, which did not allow a reliable evaluation of changes
during the treatments. The VAS scores showed higher relaxation, lower focus and
lower energy level after treatment compared to the baseline (Figure 12). Volun-
teers felt the most relaxed after the Verum situation. However, changes in VAS
scores before and after the measurements were not statistically significant, and
there were also no significant differences between situations (see Table 9).
After completed Control and Verum situations, volunteers were asked to eva-
luate which measurements made them feel more focused. Due to double-blind
and randomized research setting, the possible answers were (A) today’s mea-
surement made me feel more focused, (B) the previous measurement made me
feel more focused, (C) both the same, (D) I haven’t noticed any differences. Re-
sults showed that 63% of volunteers felt more focused after the Control, and 29%
after the Verum situation (Figure 14).
4. Discussion and Conclusion
4.1. Interpretation of the Results
During the measurements, the situation for the volunteers was a bit stressful be-
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cause they had to perform the Clock test. Solving the test generates a tense psy-
chological state. Therefore, by using the test we killed two birds with one stone:
a) we were able to directly measure various attention parameters of volunteers
and b) the situation was similar to the tense daily experience of many people.
The applied MF stimulation was in this way closer to real-life than the majority
of test situations that put volunteers under more artificial conditions. However,
as described below, this situation brought also some drawbacks.
Figure 12. VAS scores of relaxation, concentration and energy level before and after the measurements (see the
legend below graph bars) with Control, Verum and Informed. Shown are mean values ± standard error (N = 21).
Table 9. Comparison of changes in average VAS scores (values after—before) between
Control and Verum situations (N = 21).
VAS parameter
p value (paired t-test)
Relaxation
0.175
Concentration
0.666
Energy
0.566
Figure 13. Differences in VAS score before/after the measurements for each parameter
and all three situations that follow from the results presented in Figure 12.
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Figure 14. Volunteers’ judgment of the situation that should provoke a higher focus after
concluding both double-blind tests (N = 25 volunteers).
In this respect, it is important and interesting that generally, the stimulation
enhanced relaxation and worked in an anti-stress sense. The relaxing effect was
strongly demonstrated by the SC parameter that can be seen even from the very
beginning of measurements (see Figure 3) when the volunteers have already
been stimulated for 10 minutes. Here, we may also observe some measure of an
expectation (placebo-like, augmenting effect) at work, since the volunteers in
Informed situation achieved significantly lower SC values than the ones in Ve-
rum. The difference even increases in the last 10 minutes of measurements. A
similar outcome is given by HR (Figure 5), where the expectation seems to be at
work more at the beginning while gradually fading towards the end of the mea-
surement. The blind stimulation (Verum) effects, however, increased during
measurements.
The parameters TED (Figure 4) and TMP (Figure 6) yielded statistically sig-
nificant differences between Control and any of the MF stimulating situations
(Verum or Informed). With both parameters, different as they are, the outcome
speaks about a lower stress (see also [37] for TED and [38] for temperature). Es-
pecially with temperature, we may again see a positive influence of expectation
that increased the effect of MF stimulation.
In general, the brainwaves’ differences do not corroborate direct entrainment.
This is most conspicuous with beta waves (Figure 9) that demonstrate no dif-
ferences between situations. We assume the reason lies in the nature of the expe-
rimental situation involving the Clock test throughout measurements, which
demanded a full commitment of the volunteer. Consequently, beta waves have
already been at their high intensity and the entrainment could not show itself,
which we regard as one of the above-mentioned drawbacks of this specific re-
search situations. If we compare the proportions of beta waves in this experi-
ment and the one involving relaxation entrainment research [39] with no task to
be performed during the measurements, we observe that all beta values of the
former are much higher than even the highest beta value of the latter (Figure
15).
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Figure 15. Beta values for three situations in the present vigilance research (solid lines) and the experiment with
relaxation entrainment (dotted lines).
With alpha waves (Figure 7) we may observe an increasing trend in Verum, a
weaker trend of the same kind in Informed and an opposite trend (decreasing)
in Control. Here, the stimulated situations have the same sign again and are op-
posite to the blind non-stimulated one (Control). This further confirms the in-
fluence of the MF stimulation that may be a little modified by expectations and
works in the direction of increasing relaxation. These brainwave measurement
results highly conform to the results of other physiological tests measuring the
autonomous nervous system’s response.
Delta waves, however, demonstrate a different trend. In both MF stimulated
situations their values are higher from the Control (significantly in case of In-
formed vs. Control) at the beginning (deeper relaxation), but become more or
less equal to Control in the last measurement part. We interpret this as a gra-
dual, although statistically not significant, effect that is in harmony with the en-
trainment model.
The VAS measurements, although not yielding significant differences, support
the observed relaxing effect of MF stimulation on physiological parameters and
alpha waves (Figure 13).
It is relevant to notice that in all cases of statistical differences between all
three situations (see Table 4), the Informed situation differs from the Verum
one in the same direction vs. Control, meaning that expectations of being stimu-
lated in the direction of higher attention, work in the same senserelaxingas the
MF stimulation itself. From this, we may indirectly infer that the applied MF sti-
mulation supports vigilance. This is further corroborated by the Clock test re-
sults, which do not show a higher proportion of correctly detected skips or shifts
(higher accuracy), yet demonstrate a) a significantly lower proportion of error
responses of total dot shifts and b) a conspicuously lower mean reaction time
with the Informed situation. Both these results speak in favor of higher atten-
tion, although the effect discloses itself in a stronger manner with the Informed
situation where the conjunction between MF stimulation and expectations is at
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work.
4.2. Conclusion
Statistically significant differences between the Verum and the Control situa-
tions (after Holm-Bonferroni corrections) for various physiological parame-
ters strongly confirm the objective bioeffects of the stimulating MF of the
Omnipemf device.
The expectation of higher vigilance (present in Informed situation) improved
the impact of the MF itself (Verum), which is mainly indicated by the same
direction of the effect vs. Control, especially when there was a statistically
significant difference between Verum and Informed (SC, TMP parameters).
This was further confirmed in the Clock test with the error rate parameter
and especially with the mean reaction time.
However, we find the lowest number of significant differences regarding
physiological parameters in comparisons between both stimulating situa-
tions, Verum and Informed, where only three such differences were found.
This indicates that the applied MF itself induced the majority of differences
against shame exposure and that expectations only improved this impact.
Surprisingly, brain activity did not demonstrate important differences be-
tween different situations; consequently, the entrainment effect has not been
confirmed. We assume that volunteers were already fully engaged in the
Clock test so that their brain activity reached a plateau as we may convin-
cingly perceive in Figure 15.
VAS measurements in the relaxation parameter corroborated the electrophy-
siological ones.
Relaxation, better nervous energy conservation and better performance (re-
duction of errors) may be concluded from all parts of the research.
The fact that expectations of enhancing attention effect worked in the same
sense as the blind MF stimulation corroborates the assumption that the MF
stimulation regime used in the research acted in the direction of enhancing
vigilance, although the volunteers, in general, did not recognize, when they
were under stimulation (Figure 14).
4.3. Guidelines for Future Research
The future research on this line should include
situations with no specific task to be performed during the measurements,
duration of physiological and psychological changes after the end of stimulation,
some other combinations of frequencies regarding optimization of entrain-
ment,
inclusion of positive control (guarana for instance) into the research,
research of pure placebo (no stimulation, but told as if stimulated) influence,
optimization of VAS questions,
using some alternative tests measuring vigilance.
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Acknowledgements
This work was supported by MDCN Technologies Inc. New York, USA and
MDCN Tech Ltd. Slovenia, EU. We would like to thank Vesna Periček Krapež
and Mateja Senica for reviewing and correcting the manuscript.
Conflicts of Interest
The authors declare no conflicts of interest regarding the publication of this pa-
per.
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OALib
Journal
, 6, 5741. https://doi.org/10.4236/oalib.1105741
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Relaxation is becoming increasingly important in modern stressful times. Besides special psychological practices or consuming pharmaceuticals, one can achieve a more relaxed state also by applying an appropriate magnetic field stimulation of the head (low-intensity rTMS). Following the entrainment model, we did the research using carefully chosen frequencies of modest MF intensity that followed the principles of clinical trials. Besides the situations of blind verum stimulation and the sham one, we tested also the situation that included expectations of the applied stimulation. The testing was done by electrophysiological methods and VAS. The results demonstrated an objective relaxing effect of MF stimulation, where drowsiness was not stimulated. This outcome is much more evident from electrophysiological data than from the VAS ones. From the latter results, we noticed even a slightly negative reaction to expectations.
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Identifying strategies that aid in recovery from stress may benefit cardiovascular health. Ninety-nine undergraduate meditation novices were randomly assigned to meditate, listen to an audio book, or sit quietly after a standardized stressor. During recovery, meditators’ heart rate variability and skin conductance levels returned to baseline, whereas only heart rate variability returned to baseline for the audio book and control groups. Positive and negative affect were no different than baseline following meditation, whereas, both audio book and control groups had lower positive affect and higher negative affect following the intervention. Findings suggest that the sympathetic nervous system is uniquely affected by meditation, and novices may benefit emotionally from meditating after a stressor. Further research is needed to determine meditation’s utility in recovering from stress.
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Solitons or polarons, as self-reinforcing solitary waves, interact with complex biological phenomena such as cellular self-organization. Such soliton models are able to describe a spectrum of electromagnetism (EM) modalities, that can be applied to understand the physical principles of biological effects in living cells, as caused by endogenous and exogenous electromagnetic fields, on the basis of quantum coherence. A bio-soliton model was earlier developed by us, that enables to predict which eigen-frequencies of non-thermal EM waves, are life-sustaining and which are, in contrast, detrimental for living cells. The particular effects of the proposed coherent wave pattern are exerted by a range of EM-wave eigen-frequencies of one-tenth of a Hertz till Peta Hertz, representing a pattern of twelve bands, that can be positioned on an acoustic frequency scale. The discrete pattern was revealed by a meta-analysis of 219 published papers of biological EM-radiation experiments, in which a spectrum of non-thermal EM fields were exposed to living cells and intact organisms. In follow-up studies, we analyzed 120 articles on cancer-promoting and inhibiting EM fields, of which the frequency patterns fully confirmed the inferred model. Finally we analyzed experimental data out of 27 recent publications on laser mediated radiation therapy, for a spectrum of disorders such as traumatic brain injury, depressive disorders and neurological defects, confirming the general predictive force of our life algorithm. It is postulated that long-distance control of cellular morphology and fine tuning of cellular networks by soliton-waves, is instrumental in providing a morphogenetic field that maintains cellular health. The latter also may have played a role in the initiation of first life in biological evolution. The particular parametric resonance may provide positional information and cues to regulate organism-wide system properties like anatomy, control of reproduction as well as gene expression and repair. In addition, potential damaging effects of non-ionizing electromagnetic fields on life systems can be counteracted by dedicated phyllosilicate (clay) nano-materials, that were shown by us to exhibit semi-conducting EM field properties. A related protective technology was designed on the principle of toroidal trapping, since torus geometry adequately generates a coherent field of frequencies and thereby induces coherent oscillations of macromolecules. Our papers, collectively, picture the rapidly growing and dynamic field of molecular electromagnetics, that currently shows promising clinical effects in the treatment of various sincere, and often, chronic diseases. The discovered frequency patterns might be interpreted as hidden variables in Bohm's causal interpretation of quantum mechanics theory. The life algorithm detected and called by us the GM-scale, may highlight a presently unknown bio-physical (de)stabilizing principle that underlies (de)coherence of quantum wave oscillations in animate and also some non-animate systems.
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Background and aims: The Visual Analogue Scale (VAS) is a popular tool for the measurement of pain. A variety of statistical methods are employed for its analysis as an outcome measure, not all of them optimal or appropriate. An issue which has attracted much discussion in the literature is whether VAS is at a ratio or ordinal level of measurement. This decision has an influence on the appropriate method of analysis. The aim of this article is to provide an overview of current practice in the analysis of VAS scores, to propose a method of analysis which avoids the shortcomings of more traditional approaches, and to provide best practice recommendations for the analysis of VAS scores. Methods: We report on the current usage of statistical methods, which fall broadly into two categories: those that assume a probability distribution for VAS, and those that do not. We give an overview of these methods, and propose continuous ordinal regression, an extension of current ordinal regression methodology, which is appropriate for VAS at an ordinal level of measurement. We demonstrate the analysis of a published data set using a variety of methods, and use simulation to compare the power of the various methods to detect treatment differences, in differing pain situations. Results: We demonstrate that continuous ordinal regression provides the most powerful statistical analysis under a variety of conditions. Conclusions and implications: We recommend that in the situation in which no covariates besides treatment group are included in the analysis, distribution-free methods (Wilcoxon, Mann-Whitney) be used, as their power is indistinguishable from that of the proposed method. In the situation in which there are covariates which affect VAS, the proposed method is optimal. However, in this case, if the VAS scores are not concentrated around either extreme of the scale, normal-distribution methods (t-test, linear regression) are almost as powerful, and are recommended as a pragmatic choice. In the case of small sample size and VAS skewed to either extreme of the scale, the proposed method has vastly superior power to other methods.
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Neural oscillations in the theta band have been linked to episodic memory, but it is unclear whether activity patterns that give rise to theta play a causal role in episodic retrieval. Here, we used rhythmic auditory and visual stimulation to entrain neural oscillations to assess whether theta activity contributes to successful memory retrieval. In two separate experiments, human subjects studied words and were subsequently tested on memory for the words (“item recognition”) and context in which each had been previously studied (“source memory”). Between study and test, subjects in the entrainment groups were exposed to audiovisual stimuli designed to enhance activity at 5.5 Hz, whereas subjects in the control groups were exposed to white noise (Expt. 1) or 14 Hz entrainment (Expt. 2). Theta entrainment selectively increased source memory performance in both studies. Electroencephalography (EEG) data in Expt. 2 revealed that theta entrainment resulted in band-specific enhancement of theta power during the entrainment period and during post-entrainment memory retrieval. These results demonstrate a direct link between theta activity and episodic memory retrieval. Targeted manipulation of theta activity could be a promising new approach to enhance theta activity and memory performance in healthy individuals and in patients with memory disorders.
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We report experimental validation of the existence of so-called the sleeping rebound phenomenon against each sensory stimulus using a driving simulator and the electroencephalograph for about 105 subjects with evaluation of an arousal index (α + β)/(δ + θ) in the electroencephalogram measurements after each driving operation. We found that methods using the perfume presentation, the alert presentation, the vibration, and chewing gum were resulted in the sleeping rebound phenomenon, while a proposed magnetic stimulation showed an arousal retention effect without the sleeping rebound. Mechanisms of the arousal effect of the magnetic stimulation were discussed with measurements of electric conductivity versus water temperature characteristics of pure water.
Article
Caffeine induces positive effects on sustained attention, although studies assessing the acute effects of low caffeine dose (<75 mg) on sustained attention are limited and use short-term tests. Therefore, we investigated the acute effects of a 60 mg dose of caffeine on sustained attention in tests lasting up to 45 minutes using 82 low or non-caffeine-consuming healthy male (n=41) and female (n=41) adults aged between 40 and 60 years. Vigilance was measured using Mackworth Clock test, Rapid Visual Information Processing Test, adaptive tracking test, saccadic eye movement and attention switch test. Effects on mood and fatigue were analysed using Bond and Lader and Caffeine Research visual analogue scales, and Samn–Perelli questionnaire. Saliva sampling was performed for both compliance and caffeine pharmacokinetic analysis. Administration of a 60 mg caffeine dose resulted in a significant improvement in sustained attention compared with the placebo. Also a significantly improved peak saccadic velocity and reaction time performance was found, and decreased error rate. Significantly increased feelings of alertness, contentment and overall mood after caffeine treatment compared with placebo were observed. This study demonstrated that in healthy adult subjects oral administration of a single 60 mg caffeine dose elicited a clear enhancement of sustained attention and alertness, measured both in multiple objective performances and in subjective scales.
Article
It is suggested that electromagnetic quantum vacuum fluctuations are at the very deep root of the so-called “specific ions effects” in concentrated solutions or in living cells. A many-body quantum-mechanical frame of thinking is proposed based on the concept of quantum coherence taking into account explicitly density and excitation frequencies of molecules and/or ionic species. It is also proposed that Hofmeister phenomena could have a natural explanation in the harmonic relationships between sets of characteristic frequencies ruled by quantum mechanical laws. It then follows that physical chemistry of concentrated media and biology should be ruled more by a quantum “symphony” between indistinguishable constituents rather than localized two-body electrical interactions between molecular or ionic species.