A comprehensive review of the psychological effects of brainwave entrainment

Abstract

Brainwave entrainment (BWE), which uses rhythmic stimuli to alter brainwave frequency and thus brain states, has been investigated and used since the late 1800s, yet many clinicians and scientists are unaware of its existence. We aim to raise awareness and discuss its potential by presenting a systematic review of the literature from peer-reviewed journals on the psychological effects of BWE.
Terms used to describe BWE and psychological outcomes were used to search English language studies from OVID Medline (1950-2007), PsychInfo (1806-2007), and Scopus.
Twenty studies selected satisfied the following criterion: studies needed to use rhythmic stimuli with the aim ofaffecting psychological outcomes. Peer-reviewed experimental and quasi-experimental studies were accepted. Case studies and review articles were excluded. Psychological outcomes were measured using standard assessment methods or as deemed appropriate by peer review.
Other clinical measurements, including electroencephalogram response, galvanic skin response, and neurotransmitter levels were not included.
Psychological outcomes addressed cognition, stress and anxiety, pain relief, headaches or migraines, mood, behavior, and premenstrual syndrome (PMS). Protocols included the use of single, alternating, ascending, or descending frequencies or were determined by the subject, using auditory and/or photic stimulation. Studies examined single session effects and/or longer-term multiple session effects.
Findings to date suggest that BWE is an effective therapeutic tool. People suffering from cognitive functioning deficits, stress, pain, headache/migraines, PMS, and behavioral problems benefited from BWE. However, more controlled trials are needed to test additional protocols with outcomes.

Full text

REVIEW ARTICLE
A
COMPREHENSIVE REVIEW OE
THE
PSYCHOLOGICAL
EEEECTS
OE
BRAINWAVE ENTRAINMENT
Tina L. Huang,
PhD;
Christine Charyton,
PhD
Objective
•
Brainwave entrainment (BWE), which uses rhythmic
stimuli to alter brainwave
frequency
and thus brain
states,
has
been
investigated
and
used since
the
late 1800s,
yet
many clinicians
and
scientists
are
unaware ofits existence.
We aim to
raise awareness
and discuss
its
potential
by
presenting
a
systematic review ofthe
literature from peer-reviewed journals
on the
psychological effects
ofBWE.
Data Sources
•
Terms used
to
describe
BWE and
psychological
outcomes were used
to
search English language studies
from
OVID
Medline (J 950-2007), Psychlnfo (1806-2007),
and
Scopus,
Study Selection
•
Twenty studies selected satisfied the following cri-
terion:
studies
needed to
use
rhythmic stimuli with the
aim
of affecting
psychological outcomes. Peer-reviewed experimental
and
quasi-
experimental studies were accepted. Case studies
and
review articles
were excluded. Psychological outcomes were measured using stan-
dard assessment methods
or
as
deemed appropriate by peer review.
Data Extraction
•
Other clinical measurements, including electro-
encephalogram response, galvanic skin response,
and
neurotrans-
mitter levels were
not
included.
Data Synthesis
•
Psychological outcomes addressed cognition,
stress
and
anxiety, pain
relief,
headaches
or
migraines, mood,
behavior,
and
premenstrual syndrome (PMS), Protocols included
the use of single, alternating, ascending,
or
descending frequencies
or were determined
by the
subject, using auditory and/or photic
stimulation. Studies examined single session effects and/or longer-
term multiple session effects.
Conclusions
•
Findings
to
date suggest that
BWE is an
effective
therapeutic tool. People suffering from cognitive functioning defi-
cits,
stress, pain, headache/migraines, PMS,
and
behavioral prob-
lems benefited from
BWE.
However, more controlled trials
are
needed
to
test additional protocols with outcomes, (Altern Ther
Health
Med.
2008;14(5):38-50.)
Tina L. Huang, PhD,
is
director of research. Transparent
Corporation, Columbus, Ohio. Christine Charyton, PhD,
is a
visiting assistant professor
at the
Ohio State University
at
Newark Department of Psychology.
DISCLOSURE
Tina
L.
Huang,
PhD, is an
employee
of
Transparent
Corporation
(a
brainwave entrainment software corporation)
in
Columbus, Ohio. Transparent Corporation
has
allowed
Dr
Huang complete independence
in the
design, interpretation,
and
completion of this paper.
S
tandard treatments
for
mental
or
cognitive disorders
do
not
work
for
everyone
or
have undesirable side
effects.
In
fact, there
are few or no
satisfying solutions
for many, including
the
7%
of
children with learning
disabilities.' Brainwave entrainment
(BWE) has the
potential
to
safely
and
effectively fill this
gap, yet few
clinicians
have heard
of it. We aim to
introduce
the
reader
to BWE and
review
the
scientific literature
on its
effectiveness
to
improve
cog-
nitive functioning, mood, stress/anxiety, pain
relief,
headaches/
migraines, behavior,
and
premenstrual syndrome (PMS). Then
we will briefly examine
the
effects of various stimulation frequen-
cies
on
psychological outcomes
and
conclude with recommenda-
tions
for
future research,
DEFINITION
The term
brainwave entrainment
refers
to the use
of rhythmic
stimuli with
the
intention
of
producing
a
frequency-following
response
of
brainwaves
to
match
the
frequency
of the
stimuli.
The stimulus
is
usually either visual (flashing lights)
or
auditory
(pulsating tones).
By
those
in the
industry,
it is
also commonly
called "brain entrainment," "audiovisual entrainment (AVE),"
"audiovisual stimulation (AVS)," "auditory entrainment,"
or
"photic stimulation,"
GENERAL USE OF BRAINWAVE ENTRAINMENT
BWE
is
provided
to the
user
in the
form
of a
device that
ofren includes goggles with light-emitting diodes (LEDs) and/or
a
CD,
usually requiring
the use of
headphones.
It
also comes
in
the form
of
software, which allows
the
user more flexibility
in
adjusting individual sessions
to
his/her needs. Sessions most
commonly last from
20 to 60
minutes, during which
a
user sits
either with
his or her
eyes closed
in a
quiet setting
or,
depending
on
the
goals ofthe user
and
session used, with eyes open while
38 ALTERNATIVE THERAPIES, SEP/OCT 2008,
VOL 14, NO, 5
Psychological Effects
of
Brainwave Entrainment

working. Those with a history of epilepsy are advised against use
of photic stimulation.
The most commonly used methods of
BWE
are to stimulate
the brain at the desired frequency via auditory tones, flashing
lights,
or a combination of both. The 3 most common forms of
auditory stimulation use isochronic, monaural, or binaural beats.
Isochronic tones are evenly spaced tones that simply turn on and
off. Monaural and binaural beats are presented as 2 tones with
very similar frequencies, and the brain perceives a beat that is the
difference between the 2 pitches. The pitches are presented togeth-
er with monaural beats but fed separately to each ear with binaural
beats.
For photic stimulation, most devices use goggles with lights
or a flashing screen, and most instructions suggest that the user's
eyes remained closed. Pulses of light can be presented as different
waveforms or colors. Photic stimulation also can be presented
independently to each eye or each visual field in order to more
effectively target stimulation to the right or left hemisphere.
HISTORY
The first known clinical application of
BWE
was discovered
by a French psychologist, Pierre Janet, in the late 1800s. Janet
noted that his patients appeared calmer after being exposed to a
rotating strobe wheel that was illuminated by a lantern, and thus
he used this method therapeutically as needed.^ After Berger
showed that electrical activity could be recorded from the human
brain in 1929,' Adrian and Mathews (1934) showed that the
Berger rhythm (alpha) could be further amplified by photic stim-
ulation at the same frequency.'' In 1942, Dempsey and Morison
found that BWE could also be induced by a tactile stimulus,' and
Chaitran reported entrainment effects with an auditory stimulus
in 1959.'^ Psychological effects of BWE were further explored in
1946 when flickering light produced frequency-dependent sensa-
tions of "pattern, movement and color."' In 1959, BWE was
found to reduce the need for anesthesia during surgery," and in
1975,
it was found to enhance meditation.' The development of
BWE tools proliferated after Oster's 1973 article on the proper-
ties of the binaural beat.'" Research on the effects of BWE on
pain, headaches, migraines, anxiety, and stress followed in the
1980s and expanded in the 1990s to include learning and memo-
ry, ADHD, learning disabilities, behavioral problems, and PMS.
CURRENT THEORIES ON BRAINWAVE ENTRAINMENT
MECHANISMS
Placement of sensors on the scalp allows the measurement of
brainwave patterns that reflect the current state of an individual.
The best studied brainwave frequencies range from the slower
delta frequencies (1-4 Hz), which are associated with deep sleep;
to theta frequencies (4-8 Hz), which are associated with light
sleep,
creativity, and insight; to alpha frequencies (8-12 Hz), which
reflect a calm and peaceful yet alert state; to beta frequencies
(13-21 Hz), which are associated with a thinking, focusing state;
to high beta frequencies (20-32 Hz), which are associated with
intensity or anxiety." Research shows that presentation of
a
con-
sistent rhythmic stimulus (usually either a pulsating light or a
tone) within 8 to 10 Hz causes brainwaves in the occipital lobe,
parietal lobe, or temporal cortex to exhibit a frequency-following
response that either resonates with the presenting stimulus or
shows a ftequency harmonic or a sub-harmonic of a stimulus.''^"
Although many believe that the same mechanism applies to other
frequencies, this has been harder to substantiate. Recent research
suggests that baseline electroencephalogram
(EEG)"
or emotional
lability" may influence post-stimulus EEG changes. Most
researchers agree that emotional or cognitive changes do correlate
with changes in the EEG but how or whether the EEG changes is
likely to be dependent on the individual's current state.
METHODS
Search Strategy
Ovid Medline databases (Ovid Medline [1950-2007], in pro-
cess,
and other non-indexed citations), Psychlnfo (1806-2007),
and Scopus (1900-2007) were used. All papers containing any of
the following terms were selected: visual entrainment, auditory
evoked
potentials,
auditory entrainment, brain entrainment, brain-
wave entrainment, brain stimulation, brainwave stimulation, fre-
quency following
response,
photie stimulation, photo stimulation,
photie
driving,
audio-visual entrainment, AVE, sonie entrainment,
evoked
potentials, flicker, brain AND entrainment, cortieal
evoked
response,
visual
evoked
response,
afferent
sensory
stimulation, vari-
able
frequency
photo-stimulation,
repetitive sensory
response,
brain
wave
synchronizers,
brainwave
synehronizers,
audiovisual stimula-
tion,
AVS,
auditory
stimulation,
binaural
beats,
monaural
beats,
Iso-
ehronie
beats,
or
isoehronie
tones.
To select psychological terms, we used information gathered
from professional conferences, review articles, a review of web-
sites of several of the most well-known BWE companies, and 2
unpublished manuscripts by Dave Siever
{The rediscovery
of
audio-
visual entrainment teehnology
[2000] and
The physiology
and
appli-
cations of audio-visual entrainment teehnology [2006]). Articles
containing the following clinical terms were selected:
learning
dis-
orders,
learning
disabilities,
dementia,
cognitive
decline,
Alzheimer's,
intelligenee,
IQ mental
disorders,
behavioral
disorders,
attention
defi-
cit, verbal learning, memory, creativity, depression, anger, rage,
migraine,
headache,
pain,
anxiety,
stress,
premenstrual
syndrome,
or
sleep.
We then combined the outcomes of the BWE and the psy-
chological searches. For each relevant original and review article
found, references were examined for additional papers.
Criteria for Article Selection
To be included in the review, articles had to examine the
effects of BWE using auditory or visual stimulation on psycho-
logical outcomes. The stimuli had to be delivered using either
pulses of lights or tones at frequencies hypothesized to have a
beneficial effect or a protocol based on a systematic approach
toward addressing clinical outcomes. Only original full-length
journal articles in peer-reviewed journals in English were includ-
ed. Case studies and review articles were excluded. Studies had to
be of an experimental design using a comparison group or a pre-
test post-test design. Clinical or psychological outcomes had to
Psychological Effects of Brainwave EntrainmentALTERNATIVE THERAPIES, SEP/OCT 2008, VOL 14, NO. 5 39

be measured using reliable and appropriate test procedures as
deemed by peer review. Selected studies were required to reveal
statistical outcomes, such as descriptive statistics, analysis, and P
values. The Figure shows the search strategy and number of arti-
cles retrieved for each step with each ofthe 4 databases.
Brainwave entrainment searchClinical search
Ovid (1950-2007):
Ovid(IP&NC*):
Psychlnfo:
Scopus:
27830
483
10128
29384
Ovid (1950-2007):
OvidOP&NC*):
Psychlnfo:
Scopus:
1322372
17842
725136
1438802
Combined
Ovid (1950-2007): 5525
Ovid(IP&NC*): 73
Psychlnfo: 2657
Scopus: 4051
Limited to English and humans Limited to English
Ovid (1950-2007): 3864
Ovid(IP&NC*): 66
Psychlnfo: 1922
Scopus: 3346
Limited to original articles
Scopus: 2940
Articles collectedT
Ovid (1950-2007):
Ovid(IP&NC*):
Psychlnfo:
Scopus:
References only:
19
2
20
1 additionalf
8
Limited to articles
in medical science
Scopus: 1986
20 articles selected
for review
Search Process Using Four Separate Databases
Overlapping citations were found between databases. Numbers were based on
searches conducted in June 2007
*In process and other non-indexed citations.
fScopus was the last database used.
RESULTS
Overview
Twenty articles met our criteria, and all examined 1 or more
outcomes. We categorized psychological outcomes into the fol-
lowing categories: cognition (verbal outcomes [2], nonverbal/
performance [2], attention [5], memory [3], and overall intelli-
gence and achievement [2]), stress (short-term [5] and long-term
stress/burnout [4]), pain (3), headaches/migraines (4), mood
(3),
behavioral problems (1), and PMS (1), These categories are
divided into Tables 1-5.
Nine studies used healthy subjects, 4 used subjects with
either learning disabilities or attention deficit hyperactivity dis-
order (ADHD), 3 examined subjects with migraines, 2 used
stressed subjects, 1 examined subjects with anxiety symptoms, 3
examined subjects while experiencing day surgery, and 1 includ-
ed subjects with bruxism or myofascial pain dysfunction syn-
drome. Fifteen studies were of adults, 3 of children, 1 of college
students, and 1 of elderly subjects. Studies that used children,
college students, and the elderly were primarily interested in cog-
nitive functioning and academic outcomes. Nine of the studies
used multiple sessions, ranging from approximately 7 to 100,
and another 9 studies used single sessions. Two additional stud-
ies used multiple sessions but also measured changes before and
after each session. Session lengths ranged from 0.5 seconds to 60
minutes. Frequency of sessions in long-term studies ranged from
1 session per week to 2 sessions per day. Two studies used a pro-
tocol with alternating frequencies, 11 used constant frequencies
(3 that were selected by the patient), 2 used 0.5-second frequency
bursts, 3 studies began with descending frequencies and then
ended in a single frequency, 1 study alternated between ascend-
ing and descending frequencies, and 1 study used 3 different
tapes of theta and delta but gave no further details. Among stud-
ies that used constant or alternating frequencies as specified by
the investigators, frequencies ranged from low delta to high
gamma. Nine studies used photic stimulation only, 6 used audi-
tory stimulation, 4 used AVE, and 1 compared AVE to photic
stimulation. The number of subjects in each study ranged from 4
to 108, Seven groups had fewer than 20 subjects, 10 groups had
between 21 and 40, and 3 groups had more than 40. Thirteen
studies had control groups.
Cognition
Within the 8 studies that addressed cognitive functioning, a
large range of outcomes was examined, which we categorized
into verbal skills, nonverbal skills, memory, attention, general
intelligence, or success in school as measured by grade point
average (GPA). Four ofthe 8 studies examined longer-term
changes over weeks and multiple sessions, and 4 examined
immediate eftects of BWE,
One study that examined verbal abilities in school-aged chil-
dren with ADHD used a protocol that alternated between alpha
(10 Hz) and beta (15-18 Hz) AVE." A separate study used 4
healthy adult subjects and compared the effects of theta (7 Hz)
auditory stimulation with rain sounds to rain sounds alone to
examine the same outcome (Table 1),™ The study that alternated
between alpha and beta entrainment on children with ADHD
found significant increases with a standardized reading test, "
but the study that used only a single theta stimulation with
healthy adults saw no significant improvements,^"
Nonverbal skills (Table 1) were examined in 2 studies of
children with LD or ADHD.^'
^^
There was no change with the
Raven Progressive Matrices with 12 to 14 Hz photic stimula-
tion.^' However, in a separate study, 30 children were alternately
exposed to an excitatory program (starting at 14 Hz and increas-
ing to 40 Hz) and an inhibitory program (which started at 40 Hz
and decreased to 14 Hz) over 6 weeks.^^ These children showed a
significant improvement with arithmetic using WISGIIl, sug-
gesting that incorporation of gamma frequencies (38-42 Hz)
should be examined further as a potential method to improve
nonverbal skills such as math.
40 ALTERNATIVE THERAPIES, SEP/OCT 2008, VOL 14. NO. 5 Psychological Effects of Brainwave Entrainment

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i'w-
((ut'iK}'
stiíHLilafion :isso(ia[L-d witli tnL'ritm rea\i;ifitioii
in
oi^iu-
tiu'l} healthy middle-aijed adiilís
and
seniors, liolfi studies
eonfínded ihnl
the
most iri^í!rams
wvw
rt-i-oL;n¡/i.-d i\iíh
id- or
](i-2-ll7stiiiHilalioiL
In a
sepárale Mud\.
;i
sin^^ic iUi-niinuíe
ses-
sion
oí
tlieta stinmknioii
in
lu-ultln- adults rx-duced immediate
rt^rali usin^llie ¡íey \iidiíor\ \eihal lisi Tesí íonipared
lo
sessions
with
no
l'jWl.,
luo siiidies used pliolie slminlation
M
it
h orv\ithoul eíeetro-
dernuil stimulaíion lI'PK)
al
dilfereni Irequcncies
to
exaitiiiie
its
eífect
on
i^eneml inlellj^yeiu'e
ni ( .f
\
iTalik-
1 j,
The
studies seleetc-d
ehikh-en with M)i¡!)
nr
coueije studetits with "acLidcmir ehal-
len^es"
ami
tomul (iiat stimiikition
oí 14 í ¡z
alteriíaíin^i; with
22
í{/''
or 12 to 14 Hz
over multiple sessions resullcd
in
sionilicant
impnnenients
on (d'A or ihe
Scliolastir Arhievenient Wechsler
lnili\1tlual Ai.iiie\( nient Test. ^
Stress
and
Aii\ift\
Seven artiek's ex.iniined slress
;tnd
anxiet\, \\¡]i:h
ni
divided
inio short-tenn stress reliet'arid k^iL'-tenii slress/hurnoui (Table
2).
01 llie ^) studies lliat exaiuined s|iort-(erni stress (Tah!c
2).
:>
useil
nuditon sliniiikition, •
1
sUiiK used
\\l.'
aiKt
a
liitli compared
^íi'l.l^
Al
II K\AI :\'I ¡111
sii
20;;,s
Vol

TARI.E2Stn,'ss/Bíin)oui'
StixK
Short-term Stn>ss
Stimulation
(Fhotic/
StuíK (lesión Aud/VVE)
l'niportioii
ol sit
í)íiniíio!i
ofscssion ment
lurseeUil. \W> kl (l'hotif): \''' l'u-'.spoM tor l'holie with Itl M/l[]hotii)
1
hrdnr- Sinje 'iiendtouarJ<ldlli^'renee
^21.•\^
l'): 10 i I \-sl2\s( sounds oj vs 11) H/1
AV
i'I in;jdeii!ai session hrts^een i. ,::;oup<!ndeaeh k
t • ](i waMs vs vs iKHie proceikire <;roupoii denial leari|uestion-
adulis"etlin>' .^'^ i vsni'ik-
IKIIH'
OsM-iiíiard,2(HK>
voot raiiiil
ol
pus:
lor \\'¡
iO 11/,
-^j
iniíi
I'lll/,
Bda:
'i tiiin
!ii'i I/.
r> tnii) 2,~jll/.
siuük' Siiiiiilieani dittcfeiu-i-
tor h
illi
session jl|!)ia
and
IH'I;*
OJI
VIAi (sl.iU*
jn\ii't\
!.
I>M'. n>isÍL:n!tiiaiil
dil-
íi/i
[rSí•o!l;lnK•€^•'lal,
M
niiiillv
an\ii*iv
.\iid. IM'. Choose Mean: Single \ll ! lapes sho'.sed
S1;Í;I
hetueell
,T
.HI mill session etieit o\i |iii;riial Viiviel
!ape^
designed
lo reikiie;in\!-
•-)ii Ululerai iin;j
díu surgen
\ULÍ,
líl'i
\V:Í1I1I¡'1I.
20{i7h
I
hcjA
k.mdorni/cd BB
{(hitin
siouin^iíii!
BB,
rrsulnnüiii
sound
(it
rain
(
:
sound
oí
rain
I xpsriuieul;-:! m"oM;isshi",'nr.
slijnifieani ditlefeliet lisin,^
Sk\l lM.alean\iel\
1
raK ,in\ier/
g-tenii Stn'ss/lSuriKHif
lKuärd,
2(10(
I 1
{-¿¡['hii:
Vr- Pn;\spoM
tor .Vvl'
vs r2(bí'Ui) l'vsl"
r.irí' iaiililv
Hnuardcl
al.
];'8i>
h 12 vst': 11
\s
C
\lph;L ; jiniíi
4(i nun
M'Wz.
''ó
niin
inlb..
liet.i:r>
mili :'.i)fi/,
ôiiîin 2:) Hz.
2 se-.- \1BI-M einoii'inalivii.iU^tion:
sioü'.per simiiliean'.
¡
llv-'i
wnh
iiela.
ht:l
ukiorS
not
<iipli,i
uk- MBI-NI neison.Ki Ollipelnice:
sii:nitiíanl e(!cei \>'idi alpha.
Imt iKit heia
MBI \l,de]iersonakx,itioM:
iin
elleu
Wkvsprii- ;-;011/ramped 22ntin
<
se^- lío!h A\
1"
.'iiui pro(;rí'ssi\e
g ilin\-n tilKub-
rt'laxatson
¡er! i'-
relaxed
tor lörnin.
ihen
S-14 I !/
íorT
min
sionsfor iv!.i\.ilion show
a
I
iníprou'-
7
wks
nienl usin;_! i'O.Vj\ ltali,>;ui'and
;iüXK ÍV). STAl (slale Jüiitniil
an\ii-!\'i. Thui sinne lempeia-
inent sfhednie.
ORI
hyselt',
pha: ]
or AM
12/1 h
Wh hada posiliveelifü
on
nRIh\'o!hiT.
Nor;k-.1
Oll
l'OMSih.osiiliiv).
elfei
'.
online sativlai tjon iisii!;;
44
AI I I KN-M \y\- kl II
KAI"'11
s M
!'^'Oi,"l /OO.S.
VOI . ; ; ND.

Studyn
Le Scouarnec
et 14
mildly
al,
2001 anxious
adults seek-
ing treat-
ment
for
anxiety
Wahbeh, 2007a
8
healthy
adults
*E indicates experimental;
C,
control;
ry; AVE, audiovisual entrainment;
BB
TABLE
2
Stress/Burnout, cont*
Study design
Stimulation
(Photic/
Aud/AVE)HzDuration
of session
Pre vs post
Aud,
BB Choose Mean:
between
3 30 min
tapes with
theta
and
delta
designed
to
reduce
anxiety
Prevspost
Aud,
BB
Starts
at 10 60 min
with over- Hz, decreases
laying incremental-
sounds
of
ly, staying
at
rain
and 2.5
Hz
for
bells
40 min
Length
of treat-
ment
1.4-2.4/
wk for 4
wks
60
sessions
over
60
days
EflFect
No
effect with
STAI
(state
and
trait anxiety)
No
effect with STAI (state
anxiety),
and
tension/anxi-
ety
using
the
POMS
Decreased
trait anxiety using
STAI
Proportion
of significant
positive
outcomes
0/2
1/3
M, mean;
SD,
standard deviation; SEM, standard error ofthe mean; NS,
not
significant;
L,
left;
R,
right;
Hz,
hertz;
Aud,
audito-
binaural beats;
MBI,
Maslach's Burnout Inventory; STAI, Spielberger's State-Trait Anxiety Inventory; POMS Profile
of
Mood
States; TTS, Thurstone temperament schedule;
ORl
Observer Rating Inventory;
SSQ,
Stanford stress questionnaire.
photic stimulation
to
AVE.''
Two
studies
had
subjects
who
were
undergoing stressful medical procedures,
1
study
had
employees
of
an addiction care facility, another treated mildly anxious adults,
and
the
fifth
had
healthy adults. Ofthe
2
groups that stimulated
at
alpha frequencies
(10
Hz),
1
found
a
trend
but not a
significant
dif-
ference between
the
experimental groups (photic stimulation
and
AVE)
and the
control group.^'
The
other study, which compared
alpha
to
beta stimulation, found
a
significant difference after stimu-
lation
but not
between
the 2
frequencies."»
A
study that used
a com-
bination of theta
and
delta frequencies
and
another study that used
progressive slowing
fi-om
alpha
to
10 minutes of delta found signifi-
cant reductions
in
anxiety.''^' The smaller study that used just theta
stimulation
on
healthy adults found
no
significant differences
in
efFects between stimulation
and
control conditions.'"
Of the
4
studies that examined long-term stress,
2
used AVE,
and
2
used auditory stimulation with binaural beats over
4 to 8
weeks of sessions (Table
2).
Two studies treated people with stressful
occupations,
1
treated mildly anxious adults,
and
another used
healthy adults.
One
study found
no
effect
on
state
or
trait anxiety
in
the Spielberger's State-Trait Anxiety Inventory (STAI) with theta
and
delta,'"
and
another found
no
effect with state anxiety with
the
STAI
or tension/anxiety with
the
Profile of Mood States (POMS)
but did
find a difference with trait anxiety
on the
STAI with mostly delta
stimulation.'»
A
third study that compared alpha
to
beta stimulation
found significant effects
in
personal competence with alpha
and
emotional exhaustion with beta
but not
other measurements using
the Maslach's Burnout Inventory (MBI).'»
The
study that
had the
most success began
at 30 Hz and
ramped
the
fi-equency
down until
the subject was relaxed
for
15
minutes
and
then administered 8
to 14
Hz
for 7
minutes
and
found beneficial effects with
75%
ofthe
out-
comes (POMS, STAI, Observer Rating Inventory
[ORI] and the
Stanford Stress Questionnaire [SSQJ) used
to
measure long-term
stress."
Among these studies, there was
no
benefit
for
subjects expe-
riencing more stress
or
anxiety than
for
the healthy adults.
Pain
The 2 studies that examined
the
effects of either photic
or
audi-
tory stimulation
on
pain showed beneficial effects with BWE (Table
3)
32.33
j^
3
jjyjjy gf ^Q pa{jgf,j5 jggjy (-g ^pdergo their second esoph-
agogastroduodenoscopy,
20
patients
who
received
9 Hz of
photic
stimulation during surgery were compared
to 20
patients whose
goggles were turned
off. The
experimental group
had
lower pain
scores than controls,
and 18 out
of 20
who
received photic stimula-
tion experienced considerably less pain
in
comparison
to
their previ-
ous esophagogastroduodenoscopy.'' Another study used subjects
with bruxism
and
myofasical pain dysñinction syndrome
who
were
given isochronic tones of constant
fi-equency
and
duration that were
adjusted
and
selected
by the
patient
and
electromyographic
(EMG)
feedback. Subjects experienced significantly less temporal mandibu-
lar joint pain
and
muscle spasms
at
the
end
ofthe
3-week
period."
Headaches and Migraines
Of the
3
studies that examined
the
effects
of
entrainment
on
migraines
or
headaches,
1
tested
the
ability of photic stimulation
to
prevent migraines,
and
the other
2
used photic stimulation as
a
treat-
ment (Table
4). In a
study that treated subjects with frequent
migraines
at 30 Hz
over
30
days, 44%
of
subjects
and
53%
of
those
who normally
had
preceding warning signs
had a
decreased
fre-
quency
of
migraines."
A
separate study stimulated subjects with
sinusitis
or
acute, chronic,
or
migraine headaches with
1 to 3 Hz of
photic stimulation
for 5
minutes. Most people with acute
(14 out of
15)
and
chronic
(5 out of
6)
headaches experienced complete
relief,
but those with sinusitis
and
migraine headaches
had no relief."
Closer testing
of 4
patients with chronic muscle contraction
Psychological Effects
of
Brainwave EntrainmentALTERNATIVE THERAPIES. SEP/OCT 2008,
VOL. 14, NO. 5 45

TABLE 3 Pain*
Studyn
&
previous symptomsStudy design
Stimulation
(Photic/
Aud/AVE)Hz
Duration ofLength of
treatmentEffect
Proportion
of significant
positive out-
comes
Nomura, 40 adult patients getting
2006 a 2nd esophagogastrodu-
odenoscopy
E:
20,
C:
20
Randomized;
EvsC
Photic stim 9 Hz
vs goggles
with no light
10 min before Single
endoscopy session
until a few min
after ended
Manns, 14 adult patients with <1 Pre-post
1981 yr of bruxism and myo-
fascial pain-dysfunction
syndrome
Manns, 19 adult patients with >1 Pre-post
1981 yr of bruxism and myo-
fascial pain-dysfunction
syndrome
Combined Constant 3 stages: 15 Avgl4
Aud, IT and freq select- min auditory sessions,
EMG feed- ed by stim, 15 min 5/wk
back patient EMG, 15 min
in 1 ear audi-
tory stim,
other ear EMG
Combined Constant 3 stages; 15 Avg 14
Aud, IT and freq select- min auditory sessions,
EMG feed- ed by stim, 15 min 5/wk
back patient EMG, 15 min
in 1 ear audi-
tory stim,
other ear EMG
Experimental group 1/1
had a significantly
smaller amount of
pain than controls
Number of subjects
who experienced
decreased pain
compared to 1st
esophagogastrodu-
odenoscopy was
significantly higher
in experimental
subjects than con-
trols.
Reduced TMJ pain, 12/12
reduced muscle
spasm in 5 mea-
sured areas in head
and neck
Reduced TMJ pain, U/12
reduced muscle
spasm in 5 mea-
sured areas in head
and neck, except for
temporal muscle
spasm on the left
*E indicates experimental; C, control; Aud, auditory; M, mean; SD, standard deviation; SEM, standard error ofthe mean; NS, not significant; L, left; R, right; Hz,
hertz; IT, isochronic tones; TMJ, temporomandibular joint; EMG, electromyography.
headaches, using a variety of more stringent controls, confirmed
these findings.'' In a third study, 7 subjects v^iith migraines were
given red
LED
goggles and allowed to choose
a
frequency
fi-om
0.5 to
50 Hz, which they used for 5 to 60 minutes upon the occurrence of
migraines. Forty-nine of 50 migraine headaches were relieved, 36
were completely stopped, and the median duration of migraines
decreased from
6
hours to 35 minutes.*^
Mood
Three studies examined mood with auditory stimulation using
binaural beats in healthy adults. One study compared beta to theta/
delta stimulation over a single session and found that as measured by
the POMS, confiision/bewilderment and fatigue/inertia increased
and vigor/activity decreased with both session types, and depression/
dejection increased with theta/delta but decreased with beta.^' A sec-
ond study used
1-hour
sessions that began at 10 Hz and progressively
dropped to 2.5 Hz for 60 days and found no effect with depression."
In a small double-blind cross-over study, 4 adults were stimulated at 7
Hz for a single session, and as measured by the POMS, total mood
disturbance was not affected, but there was an increase in depression
score.^"
None ofthe protocols used in these 3 studies was specifically
designed or hypothesized to ameliorate depression.
Behavior
One study tested the ability of photic stimulation to positively
influence behavior in school-aged children with ADHD over multi-
ple sessions. " It used the Achenbach Child Behavior Checklist to
measure both the parental and child assessment of behavioral
change before and after 15 sessions of photic stimulation at 12 to 14
Hz, which was gradually withdrawn in cases vs controls. Both the
parental assessment and the child's self-assessment of the child's
behavior improved by approximately
70%.^'
Premenstrual Syndrome
One study found significant relief of
PMS
symptoms in women
with severe and long-standing PMS with daily photic stimulation at
46 ALTERNATIVE THERAPIES, SEP/OCT 2008. VOL J4, NO. 5 Psychological Effects of Brainwave Entrainment

Study
Noton,
2000
Solomon,
1985
Solomon,
1985
Anderson,
1997
n
&
previous
symptoms
55 adult subjects
with migraines
28 adult sub-
jects,
15 with
acute.
6 with chronic
muscle contrac-
tion headaches
3 with sinusitis.
4 with migraine
4 adult subjects
with chronic
muscle contrac-
tion headache
Treated2-3x
7 adult patients.
50 migraines
total
Study
design
Prevs
post
Prevs
post
Prevs
post for
EvsC
Prevs
post
*E indicates experimental; C, control; L, left;
Stimulation
(Photic/Aud/
AVE)
Photic
Photic
Photic vs
ambient light
on/oiFor
glass-
es on/ofF
Photic
TABLE 4 Headaches/Migraines*
Hz
Photic stim:
30
Hz,
with left eye
illuminated,
R
eye in
dark, and then reverse
using monochromatic
red light
1-3 Hz, option to have
eyes open or closed
1-3 Hz, option to have
eyes
open or closed
1st
time:
with glasses
on, ambient light ofF
2nd time:
2 subjects with glasses
off, ambient light on
3rd time:
All 4 subjects: glasses
on, ambient light on
Red LEDs in goggles.
alternating
L & R
at
0.5-50
Hz (patients
reported use in higher
freqs), eyes closed
Use
upon symptoms.
patients asked to adjust
frequency and intensity
for comfort
R, right; LED, light-emitting diode; Y, yes; N,
Duration of
session
15
min
5
min
5 min
Median
duration 30
min (range
5-60 min)
no.
Length of
treatment
Every day
for 30 days
Single
session
Single
session
Single
session
EflFect
Frequency decreased for
44%,
increased for
7%
Frequency decreased
for
53%
of those with
preceding warning signs
(ie,
auras)
14/15 subjects experi-
enced complete relief with
acute muscle contraction
headaches, 5/6 with
chronic muscle contrac-
tion headaches, and 0/3
had relief with headaches
associated with sinusitis.
and 0/4 had relief with
migraines
4/4 experienced relief for
chronic muscle contrac-
tion headache, with
entrainment; 0/6 controls
experienced relief
49/50 migraines were
helped; 36/50
migraines were stopped:
median duration of
migraine changed from 6
hrs to
35
min
Positive
finding?
(YorN)
Y for
prevention
Acute
&
muscle:
Y
Chronic
muscle:
Y
Sinusitis: N
Migraine: N
Chronic
muscle:
Y
Y
the flicker fusion point (the point at which flicker is no longer seen)
for
3
menstrual
cycles.
A
luteal
score was
calculated based on the addi-
tion of each subject s 6 most prominent symptoms and recorded each
of the 6 days prior to menses. The median luteal score dropped 64%
by the second cycle and 76% by completion. Each luteal symptom,
including depression, anxiety, affective lability, irritability, difficulty
concentrating, fatigue, change in appetite, breast tenderness, and
bloating decreased, and there
was
a trend toward a reduction in social
withdrawal. Only
1
person out of
50
did not show improvement."
Analysis by Brainwave Entrainment Frequency
To determine whether specific outcomes were associated with
specific frequencies, we also grouped studies by frequency or pat-
tern of frequency stimulation. Out of
4
outcomes that were exam-
ined with delta stimulation, only headaches/migraines^^ and
short-term stress" improved but not long-term stress^"" or
mood."™ Theta was examined in conjunction with 2 outcome-
study groups and yet showed no benefit for cognitive functioning,^»
mood,'" or relieving stress.''A single session of alpha stimulation
relieved stress for the employees of the addiction care facility'' but
not for subjects undergoing a root canal," suggesting that the effec-
tiveness of alpha could be based on the type of stress exposure.
Alpha also appeared to relieve pain'' and improve personal compe-
tence using the MBI." Trigram recognition was also most effective
at alpha in 2 separate adult populations."'^ Beta appeared to
improve attention,"" overall intelligence,'"'^ short-term stress,"
headaches,'^ and behavioral problems" and to relieve emotional
exhaustion." It had no effect on nonverbal intelligence" and
Psychological EfFects of Brainwave EntrainmentALTERNATIVE THERAPIES. SEP/OCT 2008, VOL. 14. NO. 5 47

Study
Lane,
1998
Wahbeh,
2007a
Wahbeh,
2007b
n
&
previous
symptoms
29 healthy
adults
8 healthy
adults
4 healthy
adults
Study design
Double-blind
crossover;
ElvsE2
Pre vs post
Randomized
double-blind
crossover;
E
vsC
*POMS indicates Profile of Mood States; BDI,
E
Stimulation
(Photic/
Aud/AVE)
Aud, BB
Aud, BB
with overlay-
ing sounds
of rain and
bells
BB
TABLE 5 Mood*
HzDuration
of session
Pink noise 30 min
with
BB
or
simple tones
in beta (16-24
Hz) or theta/
delta (1.5-4
Hz) through
stereo head-
phones
Starts at 60 min
10 Hz,
decreases
incrementally.
staying
at
2.5 Hz for
40 min
E:
7 Hz with 30 min
sound of rain
C;
sound of
rain only
eck Depression Inventory.
Length of
treatment
Single
session
60 sessions
over 60
days
Single
session
Effect
Comparing theta/
delta to beta;
Using
POMS,
confusion/
bewilderment increased.
fatigue/inertia increased.
depression/rejection
increased.
No effect with depression
using
BDI,
total mood
disturbance with POMS,
or with depression using
POMS
No effect with total mood
disturbance using POMS,
Increase in depression in
experimental condition
using POMS
Proportion of
significant pos-
itive outcomes
0/6
0/8
0/7
The alpha/beta protocol Improved verbal skills and
helped with attention," and in another study that used beta and
gamma stimulation, it showed beneficial effects with arithmetic
skills in children with learning disabilities and/or ADHD.^^
CONCLUSIONS
Seventeen ofthe studies were developed to confirm or chal-
lenge a hypothesis that a specific
firequency
or protocol would have
a beneficial effect on a specific outcome. Two studies generally
explored the response of subjects to stimulation at specific fre-
quencies. Another study that compared the outcome of beta to
theta stimulation hypothesized a beneficial effect of beta stimula-
tion on vigilance, but no hypothesis was made with regard to
mood.^^ Ofthe studies with specific hypotheses, there were positive
findings in the 1 group that examined verbal skills, 4 out of 4
groups with attention, 2 out of 2 with memory, 2 out of 2 with
overall intelligence and achievement, 3 out of
3
with pain, 3 out of
3 with migraines, 1 out of 1 with PMS, with the 1 study that exam-
ined behavioral problems, and the 2 studies that used theta/delta
stimulation out ofthe 4 that examined short-term stress. Although
beta stimulation was not effective for nonverbal skills, findings
fi-om 1 study suggest that the use of gamma alternating with beta
may enhance nonverbal performance skills.^^ Findings regarding
long-term stress/burnout were more mixed, but a beneficial find-
ing by Howard et aP' suggests that their protocol that began at 30
Hz and was lowered until the subject was relaxed for 15 minutes
and then used 8 to 14 Hz for 7 minutes might be worth further '
investigation. Specific protocols that used either delta and theta,^'
theta alone,™ mostly delta," or beta^' were ineffective in elevating
mood in healthy adults, but there may be other protocols that help
relieve depression in subjects diagnosed with depression.
The immediate psychological effects of memory, attention,
stress,
pain, and headaches/migraines were shown to benefit from
even a single session of
BWE.
Many practitioners and developers
of BWE tools believe that repeated exposure to BWE will allow the
user to enter the desired brain states unassisted. Indeed, the study
by Patrick,^' which found improvements in overall intelligence and
behavior, gradually withdrew the stimulus until users could pro-
duce the targeted brainwave frequencies on their own. Most stud-
ies that examined long-term efiPects did not withdraw stimulus over
a specified time period before testing, so the duration ofthe effects
are unclear. Nor are there studies that compare the effects of dura-
tion or frequency of stimulation, so it is not known whether there
is a minimal length or frequency of entrainment required to
achieve each positive outcome or if there is a limit to the intensity
of symptom relief from BWE.
Most studies used photic stimulation. However, there need to
be more studies to address the effectiveness of auditory stimula-
tion, given that it is so widely used because of its convenience.
Further studies are needed to compare the effects of auditory,
photic, and AVE stimulation at the same
firequencies
for each out-
come and to compare the clinical benefits of monaural, binaural.
48 ALTERNATIVE THERAPIES, SEP/OCT 2008, VOL 14, NO. 5 Psychological Effects of Brainwave Entrainment

Study
Carter
&
Russell,
1993
Group
1
Carters
Russell,
1993
Group 2
Patrick,
1996
n
&
previous
symptomsStudy
design
14
LD
children Pre vs
post
12 LD children Prevs
post
E:21 Prevs
C:
10 children post
for
withADHD EvsC
*E indicates experimental; C, control; Aud
TABLE
6
Behavior*
Stimulation
(Photic/
Aud/AVE)
Hz
AVE,
BB 2
min 10
Hz/1
min 0
Hz/2 min
18
Hz
AVE,
BB 2
min 10
Hz/1
min 0
Hz/2 min
18
Hz
Photic vs 12-14 Hz
nothing
Duration
of session
25
min
25
min
40-50 min
with
fre-
quent rest
auditory; AVE, audiovisual entrainment; BB,
1
Achenbacli Child Behavior Checklist and Profiles.
Length of
treatment
80 sessions
over
8
wks
18
sessions
over
6
wks
15 daily
ses-
sions, slowly
withdrew
stim as sub-
jects pro-
duced more
on their own
EflFect
Proportion of
significant posi-
tive outcomes
Significant improvement from
9/19
excessive anxiety, excessive depen-
dency, poor ego strength, poor
coordination, poor intellectuality.
poor academics, poor attention.
excessive suffering, poor anger
control
No improvement from
excessive self-blame, excessive
withdrawal, poor physical
strength, poor impulse control.
poor reality contact, poor sense of
identity,excessive sense of
persecution, excessive aggressive-
ness, excessive resistance, poor
social conformity
Significant improvement from
6/19
excessive dependency, poor
academics, poor attention, poor
impulse control, excessive sense of
persecution, excessive resistance
No improvement from
excessive self-blame, excessive
anxiety, excessive withdrawal.
poor ego strength, poor physical
strength, poor coordination, poor
intellectuality, poor reality con-
tact,
poor sense of identity, poor
anger control, excessive aggres-
siveness, poor social conformity
Significant improvement with
1/1
CBCL-P
inaural beats; ADHD, attention deficit hyperactivity disorder; CBCL-P,
and isochronic beats and the use of white noise vs music as a back-
ground. New and existing protocols based on common QEEG sig-
natures for each disorder need to be developed and tested using
standardized and validated psychological assessment methods.
Since subjects' response can depend on baseline conditions,""
population characteristics, including mental health, psychological
profile, QEEG, age, gender, and other baseline variables, should be
specified clearly. Measurement of QEEG and relevant hormones
pre-
and post-stimulation would help substantiate clinical out-
comes and improve our understanding of mechanism. Hormones
such as glucocorticoids and melatonin fluctuate during the day
and affect arousal and thus the EEG, so time of day should be kept
consistent and monitored closely. Protocols should be described
more clearly so that they can be replicated. For example, when sub-
jects are encouraged to find frequencies that make them comfort-
able,
these specific frequencies should be reported. Studies that
specifically examine the relationship between the frequency and/
or length of sessions to outcomes should be conducted. And final-
ly, larger randomized controlled trials are needed to substantiate
previous studies through clinical research.
Psychological EfiFects of Brainwave EntrainmentALTERNATIVE THERAPIES, SEP/OCT 2008, VOL. 14. NO. 5 49

In conclusion, preliminary evidence suggests that BWE is efFec-
tive in several cognitive domains and can relieve acute and long-term
stress,
reduce pain, headaches, migraines, and PMS and improve
behavior. Research has yet to prove BWE's effectiveness for mood.
Inconsistent protocols between studies were used to test each out-
come. Preliminary evidence suggests that alpha stimulation was
pref-
erable for trigram recognition, short-term stress, and pain
relief,
whereas beta was used to enhance attention, increase overall intelli-
gence, relieve short-term
stress,
and improve behavior. The alternating
alpha and beta protocol was used successfully to improve behavior,
verbal
skills,
and attention.
A
protocol that alternatively ascended and
descended from beta to gamma enhanced arithmetic skills and atten-
tion.
A
protocol that alternated between
14
and 22 Hz increased over-
all
intelligence.
Several
protocols,
including
a
combination of theta and
delta and
a
progressive slowing over
30
minutes to delta, were effective
in relieving short-term stress. Migraines were prevented with a 30-Hz
stimulus that alternated between left and right hemispheres, and
a
few
studies that allowed the subject to choose the frequency of stimulation
were successful in alleviating long-term stress, pain, and migraines. It
is
clear that more research needs to be conducted to confirm the effec-
tiveness of specific protocols to each outcome, but given the evidence
so
far, we conclude that
BWE is
worthy of further consideration by cli-
nicians
and researchers
as a
therapeutic tool.
Acknowledgments
The authors would like to thank Jane Saczynski,
PhD,
John Elliot, MPH, and Esther Boody-Alter
for their insightful comments.
REFERENCES
1.
Bloom B, Dey AN. Freeman G. Summary health statistics for U.S. children: National Health
Interview Survey,
2005.
Vital Health
StatlO.
2006 Dec:(231):l-84.
2.
Janet
P.
PsychologicäHealing A Historical ami Oiiikal
Study.
Paul
E,
Paul
C,
tiaas.
London:
Allen
&
Unwin: 1925.
3.
Berger, H. Über das Elektroenzephalogramm des Menschen.
Arch Psychiatr
Nervenk.
1929;
87:527-570.
4.
Adrian E, Mathews
B.
The Berger Rhythm: potential changes from the ocdpital lobes in man.
Brain.
1934;57(4):355-384.
5.
Dempsey E, Morison R. The interation of certain spontaneous and induced cortical potentials.
AmyP/jîsM 1941:135:301-308.
6. Oiatrian GE, Peteisen MC, Lazarte
JA.
Responses to clicks from the human hrain: some depth
electrographic obserwtions.
EkctroencephalogrOinNeuropliysioL 1960
May: 12:479-489.
7 Walter WG, Dovey
VJ,
Shipton
H.
Analysis ofthe electrical respoase ofthe human cortex to phot-
ic stimuhtion.Afatore 1946:158(4016):540-541.
8. Kroger WS, Schneider SA, An electronic aid for hypnotic induction: a preliminary n;port,
InterTUitionalJournal lyfOinica and Experimental
Hypnosis
lí)59]7.9'í-9&.
9. Willianis
P,
West M. EEG
responses
to photic stimulation in persons experienced at meditation.
Ekaroencephahgrain
Neimphysid 1975;39(5):519-522.
10.
Oster
G.
Auditory beats in the
hrain.
Sa
Am.
1973;229(4):94-102.
11.
DemosJN,(MigSíirta/Míl/iAtoiJfiM!«mtNewYoik,NY:W.W.Norton&CompanyInc.:2005:71.
12.
Toman
J,
Flicker potentials and the alpha rhythm in
man.
JNeurtiphysiol.
1941:4(1):51-61.
13.
Nyström
SH.
Effects of photic stimulation on neuronal activity and subjective experience in man.
ActaNcurvlScand.
1966:42(5):505-514.
14.
Moruzzi G, Magoun HW. Brain stem reticular formation and activation ofthe FFG, 1949./
Neuropsfáiatry Oin
Neurosa.
1995;7(2):251-267,
15.
Rogers
LJ,
Walter
DO.
Methods for
finding
single generators, with application to auditory driving
ofthe human
EFG
by complex SsmAJNeurosd
Methods.
1981:4(3):257-265.
16.
Williams JH. Frequency-specific effects of flicker on recognition memory.
Neuroscience.
2001;104(2):283-286.
17.
Rosenfëd
JP,
Reinhart AM, Srivastava
S.
The eftects of alpha (10-Hz) and beta (22-Hz) "entrain-
ment" stimulation on the alpha and beta EEG
bands:
individual differences are critical to predic-
tion of effects,/l/p/ft>t/io/)/i)!!/ii/B/ofœftaiil997:22(l):3-20.
18.
Kumano
H,
Horie
H,
Kuboki
T,
et
al.
EEG-driven photic stimulation effect on plasma cortisol and
p;pyp?
19.
Joyce M, Siever
D.
Audio-VLsual Entrainment (AVE) program as a treatment for behavior dLsor-
ders in a school setting./WmroAfr. 2000;4(2):9-25.
20,
Wahbeh
H,
Calabrese
C,
Zwickey
H,
Zajdel
D.
Binaural beat technology in humans: a pilot study
to assess neuropsychologic, physiologic, and electroencephalographic fSçcts.J
Aliem Complement
Med.
2007:13(2):199-206.
21.
Patrick
GJ.
Improved neuronal regulation in
ADHD:
An application of
15
sessiotis of pliotic-driv-
en
EEG
neurotherapy/Wi-i/rofe 1996;l(4):27-36.
22.
Olmstead R.
Use
of auditory and vkual .stimulation to improve cogtiitive abilities in learning-dis-
abled children./JVmrofc 2005;9(2):49-61.
23.
Lane
JD,
Kasian SJ, Owens
JE,
Marsh GR. Binaural auditory beats affect vigilance perfonnance
and mood. Phfsiol
Behav.
1998;63(2):24M52.
24,
Williams
J,
Ramaswamy
D,
Oulhaj
A.
10 Hz
flicker
impmves recognition memory in older people.
BMCNeurtm. 2006 Mar
5;7:21.
25,
Budzyaski T, Jordy J, Budzynski
HK,
Tang
H,
Claypoole
K,
Academic perfonnance enhancement
with photic stimulation and EDR feedback,; JVn/rorto: ]999;3(34):U-21.
26,
Le Scouamec
RP,
Poirier
RM,
Oweas
JE,
Gauthier
J,
Taylor
AG,
Foresman
PA.
Use
of binauml beat
tapes for treatment of anxiety: a pilot study of tape preference and outcomes.
Altern 'ílier Health
Mfrf.
2001:7(1
):5M3.
27 Padmanabhan R, Hildreth AJ, Laws
D.
A prospective, randomised, controlled study examining
binaural beat audio and preoperadve anxiety in patients undei^oing general anaestliesia for day
case
surgery,/tnaœfck 2005:60(9):874-877,
28.
Ossebaard HC Stress reduction by technology? An experimental smdy into the effecls of bniin-
machines on bttmout and .state anxiety. AppI Psychopliysiol
Biofeeilbiirk
2000:25(2):93-101.
29.
Morse
DR,
Chow
E.
The effect ofthe Relaxodont brain wave .synchronizer on endodontic anxiety:
evaluation by galvanic skin resistance, pulse
rate,
physical
reactions,
and questionnaire responses,
¡ntJPsyehosom.
1993:40(]-4):68-76.
30.
Wahbeh H, Calabrese
C,
Zwickey
H.
Binaural beat technology in humans: a pilot sUidy to as.sess
psychologicand Physiologe effed.s.;/l//fmCom/)imCT¡/M«í2007;13(l):25-32.
31.
Howaid
CE,
Graham LE, 2nd, Wycof
SJ.
A comparison of methods for reducing stress among
dental ,students.;D»)/fii/Ä-. 1986:50(9):542-544.
32.
Nomura
T,
Higuchi K,
Yu
H, et
al.
Slow-wave photic stimulation
relieves
patient discomfort dtir-
/ ( )
gpggpyT
33.
Manns
A,
MÜdles
R,
Adrián
H,
The application of audiostimulation and electromyographic bio-
feedback to bruxism and myoiascial pain-dysfunction syndmme. Oral SitrgOreú Mai
OrdPathd.
1981;52(3):247-252. ,
34.
Noton D. Migraine and photic stimulation: report on a survey of migraineurs using flickering
light therapy
Complement
Ther Ntm
Midwifery.
2000:6(3):13S-142,
35.
Solomon
GD.
Slow
wave
photic .stimulation in the treatmet« of headache—a preliminary repon.
Headache.
1985¿5(8):444-446.
36.
Anderson DJ, The treatment of migraine with variable frequency photo-stimulation,
lleailaclie.
1989:29(3):154-155.
37 Anderson DJ, Legg
NJ,
Ridout
DA.
Preliminary trial of photic stimulation for premenstrual syn-
drome.; Oktet
Gynaecol
1997;17(l):76-79.
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50 ALTERNATIVE THERAPIES, SEP/OCT 2008, VOL, 14, NO, 5 Psychological Effects of Brainwave Entrainment