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Volume 31, Number 2 Summer, 2003

Launching NewParadigms ofPsychophysiologicalSelf-Regulation

Launching NewParadigms ofPsychophysiologicalSelf-Regulation

The Greatest Thing,Then, Is to Make the Nervous System Our

Ally Instead of Our Enemy.

William James

Miracles Do Not Happen in Contradiction to Nature, but Only in Contradiction to That Which Is Known to Us About Nature.

Saint Augustine


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The cover of the Summer Issue shows a graphic developed by Lynda Kirk, AAPBs new president, conveying the inspirationalmessage of her inaugural remarks as president, at AAPBs

Jacksonville conference in March 2003.This issue of Biofeedback has a number of special treats for read-

ers. Randy Neblett is the editor for surface EMG topics, and has

recruited two SEMG articles for this summer issue: an article dis-cussing a new approach for removing cardiac artifact from SEMGrecordings, and an introduction to the newly emergent field of aquatic biofeedbackusing surface EMG with patients in the

water!Katherine Gibney and Erik Peper provide a thought provoking

article on the Medicine of Fun, suggesting that biofeedback ther-apy does not have to be all serious work, and that playfulness has acritical role to play in therapy and healing. Jeff Leonards begins anew series of articles on Sports Psychophysiology, with a review of current approaches applying biofeedback and psychophysiology tosports. David Siever also begins a new series, with an introductionto the exciting use of audio-visual stimulation to entrain the brain

therapeutically. AVS has been shown to be useful in a number of applications, ranging from: 1) more effective induction of hypno-sis, to 2) assisting relaxation and sedation, to 3) improving atten-

tion in individuals with ADHD. This first article provides a history of the development of audio-visual stimulation and an overviof the relevant basic science.

Seb Striefel provides an article outlining some of the effects othe new federal privacy legislation (HIPAA) on clinical practiceBoth patient confidentiality and record keeping are significantly

affected by HIPAA. Eric Willmarth a reviews a new book editedand written by a number of AAPB members, The Handbook of Mind-Body Medicine for Primary Care . Polina Cheng reports onthe current uses of biofeedback in Hong Kong.

Finally, the News and Events section includes columns from AAPBs new President, Lynda Kirk, the new President-Elect SteBaskin, and AAPBs Executive Director, Francine Butler. News aEvents also provides a photo collage from AAPBs March annuameeting in Jacksonville, Florida, and a summary of awards presed in Jacksonville.

Proposals and Abstracts are now invited for special issues on:Complementary and Alternative Medicine for Fall 2003, andCase Studies in Clinical Psychophysiology in Spring 2004. The editor also

welcomes proposals for future special issues of theBiofeedback Magazine .

Summer 20032 Biofeedback

FROM THE EDITOR

From the EditorDonald Moss, PhD

Donald Moss, PhD


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From the Editor: Donald Moss, PhD 2

\

Confidentiality and Psychotherapy Notes 4Sebastian Striefel

Removing ECG Artifact from the Electromyographic Recording 6Thomas W. Spaulding, Lawrence M. Schleifer, EdD, Bradley D. Hatfield, PhD, Scott Kerick, PhD, and Jeffrey R. Cram, PhD

Surface EMG and the Evolution of Aquatic Biofeedback 11Ron Fuller, BA, PTA

Exercise or Play? Medicine of Fun 14

Katherine Gibney and Erik Peper Sport Psychophysiology: I. The Current State of Biofeedback 18with Athletes

Jeff Leonards Audio-Visual Entrainment: I. History and Physiological Mechanisms 21

David Siever

Review of Handbook of Mind Body Medicine for Primary Care 28Eric Willmarth

Biofeedback in Hong Kong 30Polina Cheng

Upcoming Workshops 32

From the President 1AAwards and Recognition at the AAPB Annual Meeting 3AFrom the President-Elect 4A

About the Authors: Profiles of Contributors 31

Summer 2003 3Biofeedback

Biofeedback is published four times per year anddistributed by the Association for Applied Psycho-physiology and Biofeedback. Circulation 2,100.ISSN 1081-5937.

Editor: Donald Moss PhDAssociate Editor: Theodore J. LaVaque, PhDsEMG Section Editor: Randy Neblett, MAEEG Section Editor: Dale Walters, PhDReporter: Christopher L. Edwards, PhDReporter: John Perry, PhDManaging Editor: Michael P. Thompson

Copyright 2003 by AAPB

Editorial StatementItems for inclusion in Biofeedback should be for-

warded to the AAPB office. Material must be in pub-lishable form upon submission.Deadlines for receipt of material are as follows:

November 1 for Spring issue,

published April 15. April 1 for Summer issue,

published August 5. May 15 for Fall issue,

published September 15. September 1 for Winter issue,

published January 15.Articles should be of general interest to the

AAPB membership, informative and, where possi-ble, factually based. The editor reserves the right toaccept or reject any material and to make editorialand copy changes as deemed necessary.

Feature articles should not exceed 2,500 words;department articles, 700 words; and letters to theeditor, 250 words. Manuscripts should be submittedon disk, preferably Microsoft Word or WordPerfect,for Macintosh or Windows, together with hard copy

of the manuscript indicating any special text for-matting. Also submit a biosketch (30 words) andphoto of the author. All artwork accompanyingmanuscripts must be camera-ready. Graphics andphotos may be embedded in Word files to indicateposition only. Please include the original, high-res-olution graphic files with your submission at least266dpi at final print size. TIFF or EPS preferred.

AAPB is not responsible for the loss or return ofunsolicited articles.

Biofeedback accepts paid display and classifiedadvertising from individuals and organizations pro-viding products and services for those concernedwith the practice of applied psychophysiology andBiofeedback. Inquiries about advertising rates anddiscounts should be addressed to the ManagingEditor.

Changes of address, notification of materials notreceived, inquiries about membership and othermatters should be directed to the AAPB Office:

Association for AppliedPsychophysiology and Biofeedback 10200 West 44th Ave., No. 304Wheat Ridge, CO 80033-2840Tel 303-422-8436Fax 303-422-8894E-mail: [email protected]: http://www.aapb.org

FROM THE EDITOR

PROFESSIONAL ISSUES

FEATURE ARTICLES

BOOK REVIEW AND BRIEF FEATURES

ADVANCED TOPICS:SURFACE ELECTROMYOGRAPHY

Biofeedback Volume 31,No 2Summer 2003

AAPB NEWS AND EVENTS

The articles in this issue reflect the opinions of the authors, and do not reflect the policies or official guidelines of AAPB, unless stated otherwise.


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Abstract: Confidentiality and trust are con-sidered to be critical components of psychother-apy, for without them clients may withhold information that is critical to successful treat-ment. The US Supreme Court has acknowl-edged the importance of privileged communication (confidentiality in a legal pro-

ceeding) and made a decision that binds all federal courts in both civil and legal cases toconfer privilege communication status toinformation shared by a client with his or her licensed psychotherapist in confidence during counseling. More recently, HIPAA has recog-nized the importance of confidentiality for psychotherapy notes within certain guidelines.Psychotherapy notes can be protected if certainrules are followed, such as keeping them in aseparate file. Practitioners may well want toadvocate for more stringent state laws to deal with the deficits in HIPAA for protecting client confidentiality. When more stringent,state law supercedes HIPAA.

IntroductionIn 1996 the US Supreme Court in Jaffee

v. Redmond ascribed the importance of priv-ileged communication to the communica-tion that occurs between a licensed mentalhealth therapist and his or her patient whenthat communication occurs in confidence asa part of a counseling (or psychotherapy)session (Kitchener, 2000). In that ruling theSupreme Court recognized that confiden-

tiality and trust are essential to the relation-ship that a licensed therapist has with apatient. The decision acknowledged thatprivacy is essential for psychotherapy to beeffective, essential for the patient to trustthe relationship, and important to society as

well (Kitchener, 2000).In practical terms, the decision prevented

the information given by a police officer(Mary Lu Redmond) to her therapist (alicensed social worker) in confidence frombeing disclosed in a lawsuit (privilegedcommunication) brought against her by thefamily of a man she shot and killed in theline of performing her police duties. The

decision is binding only in federal courts,but the court ruled that the privilege is notsubject to a decision by individual judgeson a case-by-case basis, rather it is bindingin all federal civil and criminal cases (Corey,Corey, & Callanan, 1998). Each state courtcan still decide whether to ignore or acceptthe decision in cases they preside over(Kitchener, 2000).

As such, practitioners still need to takecare to inform clients about the limits of confidentiality, and exercise caution whenreceiving a subpoena for their psychothera-py notes or testimony. There is always aconcern whether a specific court will grantthe psychotherapy notes privileged commu-nication status in a particular situation(DeBell & Jones, 1997).

Health InformationPortablility andAccountablility Act(HIPPA)

HIPAA defines Protected HealthInformation (PHI) as anything that

includes information that could identify apatient (e.g., name, address, phone number,social security number, insurance number,etc.) (45 CFR 164.502). Such informationis to be protected by practitioners and isconsidered to be confidential. Non-identify-ing information is not protected. The new HIPAA regulations provide a new avenue

for protecting psychotherapy notes.HIPAA established a new floor of prote

tion for PHI. The regulations provide somehelpful provisions for protecting confiden-tiality, psychotherapy notes being one of those provisions. However, some argue thathe core protection of privacy is missing

because informed consent from the client not required before sharing PHI for treat-ment, payment, or other health operations(all defined in the regulations). Many pro-fessionals who commented on the originalproposed regulations argued that requiring

written informed consent in these areas would be difficult to get and too costly (Basler, 2003). The US Department of Health and Human Services (HHS) agreedthat requiring informed consent before proceeding in treatment could negatively impact access, quality, and timeliness of services so they changed the regulations (4CFR Parts 160-164). For example, pharmacists could not fill a prescription until theclient came in and gave his or her consenthospitals could not prepare for admitting aclient for a procedure based on a physicianreferral unless the patient came in andsigned a consent form first (perhaps they have never heard of a fax machine or e-msignatures); and emergency room personne

were concerned that even getting consent soon as reasonably practical after an emergency would be an administrative burden.So, the regulations were changed.Mandatory consent for treatment, paymenand health operations was replaced by voluntary consent at the providers option,allowing them to obtain consent so as notto disrupt treatment that they deem needed(45 CFR Parts 160-164), thus largely ignoing the clients right to confidentiality and

Confidentiality and Psychotherapy

NotesSebastian Seb Striefel, PhD, Logan, UT

PROFESSIONAL ISSUES


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the right to be involved in making decisionsabout their own health.

Each of the arguments given for changingthe regulations to not mandate informedconsent seems to be a convenience issue forpractitioners who resist making changes inthe way they do things. This really bringsinto question the ethics of practitioners.Clearly, practitioners need to be able to deal

with emergency treatment issues in a timely manner, but not mandating informed con-sent before treatment in non-emergency sit-uations sets the stage for infringing moreand more on patients rights to autonomy.

It seems that some practitioners are morethan willing to compromise client confiden-tiality when it makes their job easier andmore convenient. Ethics codes generally make clear that clients have a right toexpect confidentiality unless the client is adanger to self or others, an emergency exists, breaching confidentiality is requiredby law, or the client signs a release of infor-mation form. Clients have always had aright to be informed about what the limitsof confidentiality are, e.g., if and what kindof information is to be shared for treat-ment, payment or other purposes.

According to Richard Sobel, a seniorresearch associate of the psychiatry and law programs at the Harvard Medical School,HIPAA makes it easier for practitioners andManaged Care Organizations (MCOs) to

do a broad disclosure rather than to getinformed consent. You yourself may havereceived a disclosure statement from yourhealth insurance provider or doctor in themail recently. Would you want to receivetreatment without any further input?Hopefully, practitioners will strive to thehighest level of ethical functioning by aspir-ing to involve patients by getting informedconsent wherever possible before initiatingtreatment, billing or other health opera-tions.

HIPAA legally allows professionals to dis-

cuss a patients condition or treatment atnursing stations, over the phone, withanother provider, or with a family member

without taking any precautions to preventthe information from being overheard by others (45 CFR Parts 160-164). Suchbehavior may be legally acceptable, but is itethically acceptable?

It is important for practitioners toremember that just because something isnot prohibited by law (i.e., is allowed legal-ly), does not make it ethical. AAPBs oldand new (AAPB, 1995, in press) ethicalcodes expect biofeedback practitioners toinform clients about the limits of confiden-tiality, to do all they can to protect confi-dential information, and to obtaininformed consent as an ongoing part of assessment and treatment. The AmericanPsychological Associations (2003) code of ethics has similar expectations for psycholo-gists (APA, 2003). Aspire to the highestlevel of ethical functioning.

Psychotherapy andPsychotherapy Notes

Protecting confidentiality becomes espe-cially important when dealing with very sensitive information as often happens inpsychotherapy. As already mentioned, trustand confidentiality are essential to effectivepsychotherapy. Clients may well not befrank and may not completely disclose all of the information needed by the therapist if they believe the information will not bekept confidential (Corey et al., 1998).Supreme Court Justice, John Paul Stevensin Jaffee v. Redmond said,effective psy-chotherapy depends upon an atmosphere of confidence and trust in which the patient is willing to make frank and compete disclosure

of facts, emotions, memories, and fears (Corey et al., 1998, p. 157).HIPAA requires the specific authorization

of the client (via a signed release) for theuse and disclosure of psychotherapy notesfor treatment, payment, and other healthoperations (45 CFR 164, 508 (a) (2)). Thissounds simple, but it isnt. Several condi-tions must be met in order for this require-ment to apply. The first is the definition of psychotherapy notes. Psychotherapy notesare defined as,notes recorded in any mediumby a mental health professional documenting

or analyzing the contents of a conversationduring a private counseling session (Halloway, 2003b, p. 22). Psychotherapy notes may well contain sensitive informa-tion and impressions that are not appropri-ate for placement in the medical record orgeneral client file. For special consideration,and for a signed authorization for release by the client to apply to psychotherapy notes,

they must be kept in a file separate from threst of the clients record. If not kept sepa-rate, the information may well be accessed

without specific authorization by the clienIn addition, certain information is not con-sidered to be part of the psychotherapy notes and does not require a separatepatient authorization for release. That infomation includes:

1. Medical prescriptions and monitoring2. Counseling session start and stop

times;3. Modalities and frequency of treatmen4. Results of clinical tests (testing infor-

mation); and5. Any summary of diagnosis, functional

status, treatment plan, symptoms, andprognosis or progress (Halloway,2003b).

The APA argues that testing informationand the theme of psychotherapy should beprotected because they include the gist of sensitive information (Halloway, 2003b).

APA suggests that such information not bereleased without a signed release by thepatient (Halloway, 2003b).

It should be recognized that practitionershould not automatically keep two recordson every client, one for psychotherapy andone for other information (Halloway,2003b). A separate psychotherapy noterecord should be kept only if sensitive infomation is included in the record. If sensiti

information arises during treatment, a practitioner can then create a separate file forpsychotherapy notes from that date on andthen the HIPAA protections apply.Managed Care Organizations (MCOs) arebarred from making payment contingent oa patient authorizing access to psychotherapy notes (Halloway, 2003a).

Minimally Necessary Another HIPAA provision bars MCOs

from requesting information beyond whatis minimally necessary for payment andother administrative tasks (Halloway,2003a). MCOs cannot request the com-plete record. Unfortunately, the law did nodefine whatminimally necessary means. Asuch, practitioners and MCOs are likely todefine it differently. So HIPAA does notprevent too much information from going

Continued on page 10


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Abstract: Electrocardiographic (ECG) artifact is commonly observed in EMG recorded from the torso and is a potentially serious measurement problem, especially when muscle activity is low. This artifact may result inover-estimation of absolute EMG levels, and in the identification of right/left muscle asym-metry levels where none exist. A novel method of removing ECG artifact is described in this article. An evaluation, the results of which are presented herein, indicates that (1) the new method is effective in removing ECG artifact from surface-recorded EMG and (2) the pres-ence of ECG artifact results in a significant overestimation of mean resting EMG levels.

It is well known that the heart produces astrong electrical signal that may contami-nate surface-recorded EMG. The waveformsintroduced into an EMG record by cardiacactivity are known as electrocardiographic(ECG) artifact. This source of noise is aconcern whenever EMG is recorded frommuscles in the torso of the body. An exam-ple of ECG artifact is illustrated in Figure1. This figure shows a 3-second sample of EMG obtained from the upper left- andright-trapezius muscles and left- and right-forearm extensor muscles of a 40-year-old

man during seated rest. The correspondingECG is also shown. ECG artifact is clearly evident in the left trapezius muscle (panel

A). To a lesser extent, it is also evident inthe right trapezius muscle (panel B).However, it should be noted that the arti-fact is not always observed in right trapeziusEMG. In contrast to the trapezius muscles,ECG artifact is not evident in the forearm

EMG records (panels C andD). It is typically not observedin EMG recorded from the

forearms unless a wrist-to- wrist configuration is used(Cram, Kasman, & Holtz,1998).

The magnitude of the ECGartifact may be quite large rel-ative to that of the EMG sig-nal, especially when muscleactivity is low (as duringbiofeedback training), andtherefore poses a potentially serious measurement problem.If ignored, ECG artifact may result in a significant overesti-mation of EMG activity levels.Further, the asymmetry in themagnitude of the artifactrecorded from homologoussites on the left and right sidesof the body may yield anapparent asymmetry inobserved EMG levels whennone actually exists.

Limitations of theCurrently AvailableMethods for Eliminatingor Reducing ECG Artifact

Currently, methods for eliminating orreducing ECG artifact are largely limited tohigh-pass filtering and gating (Schweitzer,Fitzgerald, Bowden, & Lynne-Davies,1979). Both methods have serious draw-

backs. Filtering the EMG signal to pass frequencies >80 Hz will substantially reduce,not largely eliminate, ECG artifact.

However, as a significant amount of theEMG signal (power) resides at frequenciesbelow 80 Hz, high-pass filtering will attenuate the signal and, hence, result in a loss ofinformation. The second strategy gating involves excluding ECG-contaminatedepochs of EMG from further processing ananalysis. Hence, it results in a loss of data.



Removing the Influence of theHeart from Surface-Recorded EMGThomas W. Spalding, PhD, Pomona, California, i Lawrence M. Schleifer, EdD, Bradley D. Hatfield, PhD,Scott Kerick, PhD, College Park, Maryland,and Jeffrey R. Cram, PhD, Nevada City, CA

Thomas W. Spalding, Ph

Lawrence M. SchleifeEdD

Bradley D. Hatfield, PhD

Jeffrey R. Cram, PhDScott Kerick, PhD


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The loss of data will be greater at higherheart rates and, at high heart rates there may not be enough data to analyze or yield reli-able estimates of EMG activity levels.

In light of the drawbacks of filtering andgating, it is difficult to know what to doabout ECG artifact. Not infrequently, theartifact is simply ignored. The sense of resig-nation regarding this problem is reflected inCram et al. (1998, p. 67), an introductory book on surface electromyography, in whichthe authors note that many practitionersaccept the ECG artifact as a fact of life and

merely educate the patient about this phe-nomenon. However, it may no longer benecessary to accept ECG artifact as a fact of life. A satisfactory solution to the ECG-arti-fact problem now seems possible. Recently,

we have explored a novel method of remov-ing ECG artifact from EMG that does notappear to suffer from the drawbacks of cur-rently available techniques. The method isan adaptation of a technique developed inthe context of respiratory research (Bloch,1983). In this article we will describe themethod and present some data whichdemonstrates its effectiveness.

Description of theNew Technique

The method was first proposed by Bloch(1983) as a means of eliminating ECG artfact from diaphragm EMG. It essentially involves electronically extracting epochs oEMG data that contain an ECG artifact

(see Figure 2); aligning those epochs on areadably identifiable feature of the artifactsuch as the R-wave peak; and ensemble-averaging the epochs. The result is a waveform that reveals the average shape of theECG artifact in the EMG record. Values ofthe ensemble average will be approximate0 when ECG contamination is absent andnonzero when ECG contamination is pres-

Figure 1. A 3-second sample of left (A) and right (B) upper trapezius EMG, left (C) and right (D) forearm extensor EMG, and ECG (E) obtained

from a 40-year-old man during seated rest. EMG signals were filtered, passing frequencies between 10 and 300 Hz, and sampled at 1 kHz. ECG was fil-tered, passing frequencies between DC and 500 Hz.ECG artifact (indicated by arrows) is evident in the

left and right upper trapezius EMG but is more prominent in the left upper trapezius muscle. No

ECG artifact is present in the forearm EMG.

Figure 2. Epochs of upper left trapezius EMG and the associated ensemble-averaged waveforconsists of 751 data points containing an ECG artifact: 250 points preceding the ECG R-wav

500 points after the R-wave peak. Each epoch is aligned on the R-wave peak. Ensemble-averby averaging data points at time 1 across all of the available epochs (i.e., epochs = 1 to N; N

ECG artifacts in the measurement interval) and then repeating the averaging process for eremaining data points in the epoch (i.e., time = 2 to 751). In this example, the result is an ens

aged waveform with a length of 751 points that represents the average influence of the ECGEMG activity. The expectation is that values in the ensemble-average will approximate 0 exce

activity is influencing the EMG.


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ent. In the final step a subtraction template, which represents the artifact (i.e., thenonzero portion of the ensemble-averaged

waveform), is aligned with each artifact inthe EMG record and subtracted from it,yielding an artifact-free data series. Figure 3shows a sample of contaminated left-trapez-ius EMG with the associated ensemble-averaged waveform (with the subtractiontemplate marked) and the corrected EMG.

Adaptation of the Methodto Surface-RecordedEMG

Variations of this basic method have beenemployed successfully in respiratory research to remove ECG artifact fromdiaphragm EMG obtained with esophageal

wire electrodes in humans (Levine, Gillen, Weiser, Gillen, & Kwatny, 1986) and hook electrodes in anesthesized dogs (Bartolo,Dzwonczyk, Roberts, & Goldman, 1996;

Bartolo, Roberts, Dzwonczyk, & Goldman,1996). We have recently adapted the tech-nique to surface-recorded EMG (Spalding,Kerick, Hatfield, Schleifer, & Cram, 2001).Our method differs from that employed inthe respiratory research in two ways. First,

we recorded the ECG with a standard con-figuration of chest electrodes and used it tounambiguously identify R-wave peaks inthe EMG records. R-wave peaks were usedto align epochs of contaminated EMG forensemble-averaging and to align the sub-traction template with individual artifactsin the EMG record. ECG was not recorded

in the previous respiratory studies. In thesestudies contaminated EMG epochs wereidentified and aligned via a cross-correlationprocedure. This procedure is probably ade-quate when applied to diaphragm EMGobtained with wire electrodes during expira-tion. Diaphragm EMG is quiescent duringexpiration and ECG artifacts can be identi-fied unambiguously. However, the cross-

correlation procedure may not be reliable when applied to surface-recorded EMG,especially if muscle activity levels are relatively high or episodes of high activity areevident. As we were interested in assessintrapezius EMG during psychological stresin computer work (Schleifer, Spalding,Hatfield, Kerick, & Cram, 2001), weexpected to observe relatively high EMGactivity levels during the periods in whichparticipants were typing on the computerkeyboard. Secondly, the subtraction proce-dure was simplified. In the previous studiethe subtraction template was adjusted viaregression to account for variation in theobserved ECG artifacts introduced by respration-related movements of the wire elec-trodes. As surface electrodes are lessvulnerable than esophageal wire electrodeto such movement artifact, this adjustment

was deemed unnecessary.

Evaluation of theEnsemble-Average-BasedSubtraction Method

In order to determine if our method waseffective in removing ECG artifact fromsurface-recorded EMG we compared con-taminated-, gated-, and corrected-EMG onmean activity level (mV rms). Left uppertrapezius EMG and ECG data wereacquired from 21 women (n = 17) andmen, aged 18 to 49 years (M = 28.3, SD =

9.1), during 5 minutes of rest while seatedand with hands in the lap. Both signals

were sampled at 1 kHz. The EMG data were dual-pass filtered, passing frequencieof 20-300 Hz. The data were dual-pass fil-tered because the initial (forward) filteringintroduces a phase shift or a displacementof the series in time. This time displace-ment is highly undesirable in our applica-tion. Hence, the data were filtered again,backwards, to correct the phase shift. Thefiltered data constituted the contaminatedseries. These data were further processed tcreate the gated and corrected series. Asindicated above, gating involves excludingfrom further analysis those epochs of EMGdata that are contaminated by ECG artifac(Schweitzer et al., 1979). Previous investitors (Levine et al., 1986; Schweitzer et al.1979) excluded epochs of a constant lengt(i.e., 380 ms). However, we determined th


Figure 3. An epoch of upper left-trapezius EMG with a prominent ECG artifact (A), associated ensemble-averaged waveform (B), and corrected EMG series (C). The corrected EMG was obtained by subtracting values of the ensemble average within the subtraction template (indicated by the vertical lines) from the

ECG-contaminated EMG. The corrected EMG series (C) shows that the ECG artifact has been completed removed without a loss of data or information.


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gate length empirically for each partici-pant individually as the interval betweenthe onset and offset of the nonzero portionof the ensemble average. Gated series wereincluded in the analysis in order to estimatethe mean level of the true, uncontaminatedmuscle activity. Although the true meanactivity level cannot be known, it seems rea-sonable to estimate it using the gated series.

As the participants were in a stable postureand state (i.e., relaxed and behaviorally inactive) throughout the recording period,it is reasonable to expect that their EMGactivity was stable and, as such, the trueactivity level in the contaminated epochs(which cannot be known definitively)should be similar to that in the artifact-freeepochs. Hence, excluding contaminatedepochs of EMG should not bias the esti-mate of the true mean activity level. Finally,the corrected series were constructed by removing the ECG artifact using theensemble-average-based subtraction tech-nique. We expected that, if the ensemble-average method was effective, the mean of the corrected EMG series would be similarto that of the gated data and, further, thatboth means would be lower than that of thecontaminated series. The results supportedthis expectation.

Comparison of MeanEMG Activity Levels for

Corrected, Gated, andContaminated SeriesMean EMG activity levels of the correct-

ed, gated, and contaminated series areshown in Figure 4. Consistent with ourexpectations, mean activity levels of the cor-rected and gated EMG series were similar(identical, in fact) and both means were sig-nificantly lower than that of the contaminat-ed series. These results indicate that theensemble-average-based subtraction tech-nique effectively removed ECG artifact fromleft-trapezius EMG and yielded an estimateof mean activity equivalent to that of thetrue uncontaminated EMG activity level.

DiscussionThe influence of ECG artifact on meas-

ures of EMG activity may depend on themagnitude of the ECG signal relative tothat of the EMG signal (i.e., the signal-to-noise or ECG-to-EMG ratio) (Bartolo et

al., 1996). Our results indicate that, whenthe ECG-to-EMG power ratio is high (as ittypically will be in biofeedback applica-tions), ECG artifact will be a significantmeasurement problem and should not beignored. In our study ECG contaminationresulted in overestimating mean left-trapez-ius EMG activity levels by 2.2 :V rms. Asmean resting levels of trapezius EMG activi-ty range from 2 - 5 mV, this error is quitelarge. As a percentage of the estimated truemean level (i.e., 3.2 mV rms), the magni-tude of overestimation was 69%.Advantages of the Method

Our method is procedurally more com-plicated than filtering or gating. The readermay, therefore, question the utility of thetechnique. The primary advantage of themethod is that it eliminates ECG artifact

while preserving the continuity of the data

series (i.e., no data are lost) and retainsinformation in the lower frequencies of theEMG spectrum. In contrast, gating resultsin a loss of data as well as produces discon-tinuities in the data series. The loss of datamay be substantial. Assuming a constantgate length of 380 ms as employed by Schweitzer et al. (1979), a heart rate of 60bpm would result in a data loss of 38%. Ata heart rate of 80 bpm, more than half (51%) of data will be lost; at 100 bpm, theloss of data reaches 63%. Hence, even forheart rates that are commonly observed at

rest, gating results in a substantial loss of data. It would seem that such losses wouldseriously compromise the reliability of measures of activity levels. Additionally, at

high heart rates, there may be an insuffi-cient amount of data to analyze.

In contrast, high-pass filtering (e.g., pasing frequencies > 80 Hz) does not result ina loss of data or produce discontinuities inthe data series. However, it does significanly attenuate the signal and results in a lossof information contained in the EMG spectrum below the cutoff frequency. Further, alow muscle activity levels such as inbiofeedback applications, high-pass filterinmay result in a disproportionately large loof information, as the relative amount of power in lower frequencies is greater atlower levels of muscle activity. With theensemble-average-based technique there ano restrictions on filter settings. The clini-cian or investigator is free to set the high-pass filter cutoff frequency at or near thelower boundary of the EMG spectrum (e.g10 - 20 Hz). Hence, the ensemble-averagebased technique should enable more of theEMG signal to be preserved. The amountof signal preserved will, of course, dependon how low the high-pass filter cutoff fre-quency is actually set.

It is worth noting that the ensemble-aveage-based technique is applicable to surfacrecorded EMG obtained from any musclesof the torso and with any high-pass filtercutoff frequency settings between 1 Hz an80 Hz. The shape and magnitude of ECGartifact will vary, depending upon the mus

cle being measured and the filter settings.However, this is not a concern because thetechnique does not require any assumptionabout the shape or magnitude of the arti-fact. The only requirements are that arti-facts be reliably identified and aligned foraveraging and subtraction, and that the signal amplification is set such that the analoto-digital converter does not saturate.

Additionally, a high-pass filter with a cutofrequency of at least 1 Hz should beemployed in order to ensure that the EMGseries is centered about a mean of 0.

Otherwise, the method should adequately model the shape of the artifact. Althoughonly one component of the ECG waveform(i.e., the QRS complex) was observed inour trapezius data, it is possible that, inother circumstances, additional componen(e.g., P- or T-waves) could be observed. Thensemble-average-based technique shouldeasily accommodate multiple components

Figure 4. Mean (+/-SE) corrected, gated, and ECG-contaminated upper left-trapezius EMG

activity levels. The mean activity level of the cor-rected EMG series was significantly lower than that of the contaminated series and was identical to that

of the gated series.


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Application of the Ensemble-Average-Based Method inClinical Biofeedback

In our study the ensemble-average-basedtechnique was applied off-line. To be of usein clinical biofeedback it must be appliedon-line and in real-time. Unfortunately, soft-

ware for removing ECG artifact on-line (oroff-line) is not available commercially.However, it seems quite possible to adaptthe method for on-line, real-time applica-tions. Given the strong interest in muscles of the torso (e.g., trapezius muscles), the ubiq-uitousness of ECG artifact, and the draw-backs of filtering and gating; it would seemthat there is a large need for such software.

Future ResearchFurther research is needed in at least

three areas. First, it is known that there arelarge individual differences in resting heartrate. The effect of such individual differ-ences on measures of EMG activity, in boththe time- and frequency-domains (e.g.,mean level in mV rms versus mean frequen-cy, respectively), is not known and meritsinvestigation. Secondly, is there a thresholdfor the ratio of ECG power-to-EMG powerbeyond which the effect of ECG contami-nation is negligible? For example, if EMGactivity is high relative to the ECG signal,can ECG artifact be ignored? The answermay depend on whether a time- or a fre-

quency-domain measure is being consid-ered. Lastly, it is unclear if individualdifferences in resting heart rate have a detri-mental effect (via ECG artifact) on skillacquisition in EMG biofeedback trainingand/or treatment outcomes (e.g., pain rat-ings). Further research in these areas willlikely clarify the extent and nature of themeasurement problem that ECG artifactposes and its impact on biofeedback therapy and applied psychophysiology.

ReferencesBloch, R. (1983). Subtraction of electrocardio-

graphic signal from respiratory electromyogram. Journal of Applied Physiology: Respiratory,Environmental, and Exercise Physiology , 55(2), 619-623.

Bartolo, A., Dzwonczyk, R. R., Roberts, C., &Goldman, E. (1996). Description and validation of a technique for the removal of ECG contaminationfrom diaphragmatic EMG signal. Medical and Biological Engineering and Computing , 34(1), 76-81.

Bartolo, A., Roberts, C., Dzwonczyk, R. R., &Goldman, E. (1996). Analysis of diaphragm EMGsignals: comparison of gating vs. subtraction forremoval of ECG contamination. Journal of Applied Physiology , 80(6), 1898-1902.

Cram, J. R., Kasman, G. S., & Holtz, J. (1998).Introduction to surface electromyography.Gaithersburg, MD: Aspen Publishers, Inc.

Levine, S., Gillen, J., Weiser, P., Gillen, M., &Kwatny, E. (1986). Description and validation of an ECG removal procedure for EMGdi power spec-trum analysis. Journal of Applied Physiology,60(3),1073-1081.

Schleifer, L. M., Spalding, T. W., Hatfield, B.D., Kerick, S., & Cram, J. R. (2001, August). Muscle activity of the upper extremities under highand low mental demands during computer work:Preliminary findings.Paper presented at the 9thInternational Conference on Human-ComputerInteraction, New Orleans, Louisiana.

Schweitzer, T. W., Fitzgerald, J. W., Bowden, J. A., & Lynne-Davies, P. (1979). Spectral analysis of human inspiratory diaphragmatic electromyograms. Journal of Applied Physiology,46, 152-165.

Spalding, T. W., Kerick, S., Hatfield, B. D.,Schleifer, L. M., & Cram, J. R. (2001, August).Cardiac signal artifact and the interpretation of trapezius muscle activity during computer workPapepresented at the 9th International Conference onHuman-Computer Interaction, New Orleans,Louisiana.

AcknowledgmentThis research was supported by a grant

(#99-0001) from The Johns HopkinsUniversity Center for InformationTechnology and Health Research.

Footnotesi Direct correspondence to: Thomas W.

Spalding, PhD, Department of Kinesiologyand Health Promotion, California StatePolytechnic University, 3801 West Temple

Avenue, Pomona, California 91768.Telephone: 909-869-2772, FAX: 909-869-4797, Email: [email protected]


to MCOs, but it does provide grounds for apractitioner to refuse to give some informa-tion (Halloway, 2003a). The courts andHHS will ultimately provide guidance onhow to defineminimally necessary (Halloway, 2003a).

Interestingly, New Jerseys psychology licensing law specifies that MCOs canrequest only: administrative and diagnosticinformation, the status of the patient, rea-sons for continuing treatment (limited toassessment of the patients level of function-ing and distress), and a prognosis(Halloway, 2003a). How well the law will

work remains to be seen. It should beremembered that anytime a state law ismore stringent than the requirements inHIPAA, state law supercedes HIPAA. Itcould be useful for practitioners to correctthe problems inherent in HIPAA by gettingmore stringent state laws passed. Perhapsthe New Jersey law could be used as a start-ing point.

References American Psychological Association. (2003).

Ethical principles of psychologists and code of Washington, DC: Author.

Association for Applied Psychophysiology andBiofeedback. (1995).Ethical principles of applied psychophysiology and biofeedback. Wheat Ridge, CO Author.

Association for Applied Psychophysiology andBiofeedback. (in press).Ethical principles of appl psychophysiology and biofeedback. Wheat Ridge, CO Author.

Basler, B. (2003, April). Medical privacy improves But, alas, not enough. AARP Bulletin44 (4), 12.

Corey, G., Corey, M. S., & Callanan, P. (1998).Issues and ethics in the helping professions (5th.Pacific Grove, CA: Brooks/Cole PublishingCompany.

DeBell, C., & Jones, R. D. (1997). Privilegedcommunication at last? An overview of Jaffee v.Redmond. Professional Psychology: Research a

Practice , 28, 559-566.Halloway, J. D. (2003a, Feb.). More protectionsfor patients and psychotherapy under HIPAA. Monitor on Psychology,34(2), 22.

Halloway, J. D. (2003b, March). A stop-gap inflow of sensitive patient information. Monitor on Monitor on Psychology , 34(2), 22. Psychology , 34(2),22. Monitor on Psychology , 34 (3), 22.

Kitchener, K. S. (2000).Foundations of ethical practice, research, and teaching in psychology .Mahwah, NJ: Lawrence Erlbaum Associates.

Confidentiality and Psychotherapy Notescontinued from Page 5


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Surface EMG and the Evolution ofAquatic Biofeedback Ron Fuller, BA, PTA, Concord, New Hampshire Ron Fuller, BA, PTA

Abstract: The union of aquatic therapy and surface EMG was derived out of necessity inorder to help validate the effects of aquatic therapy exercise and to qualify its outcomes.The technique of aquatic biofeedback has undergone several changes in its evolution.Initially, waterproofing the electrode was done

with a bioclusive barrier that was expensive and difficult to apply. Now, with the advent of a latex extremity sock that covers the elec-trode, application of the technique is mucheasier and less time consuming. The aquatic biofeedback technique is currently being used in the treatment of orthopedic and neurologic conditions, such as cerebral vascular accidents (CVAs), anterior cruciate ligament repairs, patellofemoral pain syndrome (PFPS) and spinal cord injuries.

Introduction to Aquatic

Biofeedback Biofeedback and surface electromyogra-phy (SEMG) have a well-established rela-tionship with the fields of physical andoccupational therapy. The land-based use of biofeedback in the treatment of variousupper and lower extremity conditions is

well documented and has proven to be animportant adjunct to established treatmentmethods.

Aquatic therapy has been around for cen-turies. From the community baths of Rometo the healing pools of Bad Ragaz, aquaticrehabilitation has been practiced in oneform or another by utilizing the physicalproperties of water to relieve pain and tostrengthen weakened muscles.

Extending land-based biofeedback proce-dures to the aquatic environment, however,has developed a new twist to both aquatictherapy and biofeedback. A tangential

hybrid of sorts, created out of necessity, it isa marriage of the two rehabilitative entitiesthat offers patients the best of both worlds.The aquatic environment provides buoyan-cy to unload the joints and decrease pain

while SEMG biofeedback contributes quan-titative measurement and direction for both

patient and therapist. Aquatic biofeedback now gives us the ability to quantify theexercises performed in the pool and gives usanalytical data to direct our rehabilitativeefforts in a more specific and purposefuldirection.

Techniques of AquaticBiofeedback

The aquatic SEMG treatment model isthe same as in land-based biofeedback, butit has been adapted and modified to con-form to the aquatic environment (specifical-ly, drawing on hydrodynamic principles).The same skin preparation is followed priorto the application of the sensors. The only difference is that once the set-up is com-plete, a waterproof covering (referred to as asock) is placed over the site, and theextremity can be immersed. Exercises arecarried out, and training is facilitated andpracticed, until the desired effect isachieved. Then the sock and sensors areremoved and physical therapy can continueeither in the pool or on land.

The whole process is quite easy. Thedesired muscle is selected and the site is pre-pared with an alcohol swab to remove dirtand oils (Figure 1). After placing the elec-trodes over the appropriate muscle site, the

wires from the inside of the waterproof sock are hooked up, the whole sock is pulled upover the extremity (Figure 2), and the air ispumped out to form an airtight barrier

(Figure 3). The corresponding (outer) elec-trode wires are plugged into the EMG unitand after the correct parameters are pro-grammed into the EMG unit, the biofeed-

Figure 1.

Figure 2.

Figure 3.


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back training process begins(Figure 4).Exercises are performed to either facilitate

or inhibit activation of specific musclegroups. The SEMG biofeedback signalassists with the treatment and enhances theaquatic treatment regimen. Box I shows aninstrumentation system currently availablefor aquatic use and contact information forthe relevant manufacturer.Safety Issues

When I first suggested using EMG in theaquatic environment, clinicians would look horrified at the thought of me taking suchan expensive and sensitive piece of equip-ment into the pool. The risk managementpeople literally scrambled to find me, inorder to remind me of the legal ramifica-tions of mixing water, electricity andpatients. Fortunately, the emergence of pow-erful, battery-powered, hand-held EMG

units has eliminated the need for a wallplug. Using three AA batteries in anaquatic setting significantly reduces thechance of electrocution to zero. Patients arenever at risk of harm from the unit or thetechnique. The information gathered at aparticular session is saved on the hand-heldunit and then downloaded later to a com-puter for further analysis. The only real con-cern comes from dunking the EMG unit inthe pool, and this is eliminated by placing

the unit in a waterproof box during the ses-sion. A friend of mine who has supportedand believed in the aquatic biofeedback technique was once asked (many years ago)about the possibility of using EMG in the

water. He replied that it was possible butonly once! His opinion of EMG in the

water has changed. A lot of peoples opin-ions about EMG in the water have changed.

ApplicationsI have used aquatic biofeedback with

orthopedic and neurologic patients alike -specifically with cerebral vascular accidents(CVAs), anterior cruciate ligament (ACL)reconstructions, rotator cuff tears/recon-structions, cerebral palsy (CP) and spinalcord injuries. I have also published articlestesting the validity of aquatic biofeedback,outlining its uses, and calling upon its

measurements to investigate the mecha-nisms by which progress is achieved in cer-tain conditions (Fuller, Awbrey, 1999; seealso Stowell, Fuller, & Fulk (2001).

Recently, I co-published a case study thatutilized aquatic biofeedback to validate theprogress made by a 20 year old spinal cordinjured patient one year post-injury (Stowell, Fuller, & Fulk, 2001). Our patienthad an incomplete C6 spinal cord lesionfrom an automobile accident. He was seenfor four months of land and aquatic basedphysical therapy that included ambulationtraining in the pool at various water depths(to manipulate the effects of weight bearingby utilizing buoyancy) as well as on land.

Aquatic biofeedback was used to train theabdominals, gluteals, quadriceps and ham-string muscles during aquatic exercise andto record the muscle activity of those partic-ular muscles (on land and in the pool)

throughout the 4-month treatment pro-gram. The effects of gravity on land caninhibit the patients ability to successfully stand or even walk. In the water, patients

with a muscle test grade of Trace orPoor can hold themselves upright or eve

walk. This is possible by utilizing thehydrodynamic principle of buoyancy tosupport and assist the patient. Walking wamimicked in deep water (7 ft. depth),

where the effects of gravity are almost completely eliminated, and also in the shallow

water (4 ft. depth), where the graduatedloading of the lower extremities could factate potential neural adaptations of thelocomotor circuitry at the spinal cord leve(Wernig & Muller, 1992; Wernig, Muller,Nannasy, & Cagol, 1995). Pre- and post-testing consisted of ambulation assessmenmanual muscle testing and surface EMGtesting on land and in the water. At theconclusion of the 4-month treatment inter-vention, the patient was able to ambulatefive times farther than initially noted. TheEMG readings showed significant improvement on land and in the pool, of all mus-cles tested. The final manual muscle testsshowed a decrease from the initial test reaings. Significant progress was made with tpatients functional ability and mobility inspite of the plateau he had reached withmanual muscle tests (one of the major discharge gold standards in spinal cord reha

bilitation).The emerging theory of facilitating theCentral Pattern Generator with body

weight supported treadmill gait training hashown great promise in the realm of spinacord rehabilitation. This treatment tech-nique utilizes a harness to suspend thepatient upright and a treadmill to allow stationary ambulation. The Central PatternGenerator theory suggests that assisted

walking may provide sensory stimulation, which generates an adaptation to the nor-mal neural pathway. This would occur at

the spinal cord level (more reflexive than higher level function).

Utilizing the buoyant property of waterin lieu of the harness system was easy enough to manipulate. By employing aquaic biofeedback to record the improvementand to assist with muscle training, valuablinformation was compiled that helped

Box I. AquaSense Aquatic EMG SystemsManufactured by Thought Technology Ltd.2180 Belgrave AveMontreal, Quebec, CanadaH4A 2L8Tel: (800) 361-3651Phone (514) 489-8251Fax: (514) 489-8255http://[email protected]

Figure 4.


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Abstract: Patients often equate biofeedback training homework to mandatory activities,which are often viewed as one more thing todo. Changing the perception from that of work to fun can encourage laughter and joy and help overcome a chronic pain pattern all

necessary for healing. This paper encourages therapists to explore utilizing childhood activi-ties and paradoxical movement to help patients release tension patterns and improve range of motion. A strong emphasis is placed on linking diaphragmatic breathing to movement.

When I went home I showed my grand-daughter how to be a tree swaying in the

wind, she looked at me and said, Grandma,I learned that in kindergarten!

Betty laughed heartily as she relayed this

story. Her delight in being able to sway herarms like the limbs of a tree starkly con-trasted with her demeanor only a monthprior. Betty was referred for biofeedback training after a series of 9 surgeries wrists,fingers, elbows and shoulders. She arrived ather first session in tears with acute, chronicpain accompanied by frequent, incapacitat-ing spasms in her shoulders and arms. She

was unable to abduct her arms more than afew inches without triggering more painfulspasms. Her protective bracing and rapidthoracic breathing exacerbated her pain and

contributed to limited range of motion of her arms. Unable to work for over a year,she was coping not only with pain, but also

with weight gain, poor self-esteem anddepression.

Biofeedback training began with what wefeel is the foundation of health: effortless,diaphragmatic breathing (Peper, 1990).Each thoracic breath added to Bettys

chronic shoulder pain. Convincing Betty todrop her painful bracing pattern and toallow her arms to hang freely from hershoulders as she breathed diaphragmatically

was the first major step in regaining mobili-ty. She discovered in that first session that

she could use her breathing to achieve con-trol over muscle spasms. During the first week, she practiced her breathing assiduous-ly at home and had fewer spasms. Betty wasable to move better during her physicaltherapy sessions. Each time she felt theonset of muscle spasms she would stop allactivity for a moment and go into my trance to prevent a recurrence. For the firsttime in many months she was feeling opti-mistic.

Subsequent sessions built upon the foundation of diaphragmatic breathing: boostinBettys confidence, increasing range of motion (ROM), and bringing back somefun in life. Activities included many childhood games: tossing a ball, swaying like a

tree in the wind, pretending to conduct anorchestra, bouncing on gym balls, playingSimon Says (following the movements othe therapist), and dancing. Laughter andchildlike joy became a common occurrencShe looked forward to receiving the sparkstar stickers she was given after successfusessions. With each activity Betty gainedmore confidence, gradually increased ROMand began losing weight. Although she hasome days where the pain was strong and


Exercise or Play?

Medicine of FunKatherine H. Gibney and Erik Peper,San Francisco, CA

FEATURE ARTICLE

Erik Peper Katherine H. Gibney

Figure 1. Perform physical activity that could aggravate pain only during the exhalation phase pain sensations. Discomfort can usually be minimized if activity (movement or treatment that pain, such as an injection) is performed or given during the exhalation phase. During the inhaone pauses with the activity and resumes during the exhalation phase. The activity commencethe initiation of exhalation and when the heart rate has started to decelerate.


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Movement Reeducation Be Oppositional And DoIt Differently

Movement reeducation, such asFeldenkrais, Alexander Technique orHannah Somatics, involves consciousawareness of movement (Hanna, 1988;Murphy, 1993). Many daily patterns of movement become imbedded in our con-sciousness and, over the years, may includea pain trigger. A common trigger is liftingthe shoulders when reaching for the key-board or mouse. Patients suffering fromthoracic outlet syndrome (TOS) often havesuch patterns. A keyboard can often inad-vertently cue the patient to trigger this dys-

ponetic, and frequently painful, pattern.Have the patient do movement reeducationexercises in which they are guided throughpractices in which they have no expectancy and the movements are novel. The focus ison awareness without triggering any fight/flight or startle responses.

Ask the patient to explore performingmany functional activities with the oppositehand, such as brushing her hair or teeth,eating, blowing her hair dry, or doinghousehold chores, such as vacuuming. (Try this for yourself, as well!). Be aware of how much shoulder muscle tension is needed toraise the arms for combing or blow-dryingthe hair. Explore how little effort is requiredto hold a fork or knife (you might want to

do this in the privacy of your own home!)Do movements differently such as, practicing alternating hands when leading with thvacuum or when sweeping, changing route

when driving/walking to work or the storegetting out of bed differently. Or, break uphabitual conditioned reflex patterns such aeye, head and hand coordination. Forexample, when doing a movement, slowlyrotate your head from left to right andsimultaneously shift your eyes in the opposite direction (e.g., turn your head fully tothe right while shifting your eyes fully tothe left, and then reverse) or before reachiforward, drop your elbows to your sidesthen, bend your elbows and touch yourshoulders with your thumbs then, reach fo

ward. Often, when we change our patterns we increase our flexibility, inhibit bracingand reduce discomfort.

Youthful Playing Pavlovian PracticeRemember the story of Pavlov in the ho

pital? Many, including his family, thoughthe was slipping into death when he quietlylay in his hospital bed and gently played

with a bowl of water and dirt. Yet, the nexmorning he awoke and ate a hearty break-fast. Soon he was out of the hospital. Pavlknew that evoking the playful joy of childhood would help to encourage mental andphysical healing (Peper, Gibney, & Holt,

2002). Having patients play can encouragelaughter and joie de vivre, which helps inphysical healing. Often being involved inchildhood games or actually playing thesegames with children removes one from wories and concernsboth past and futureand allows one to be simply in the present

Just being present is associated with playfness, timelessness, passive attention, creatity and humor. A state in which onespreconceived mental images and expectanciesthe personal, familial, cultural, andhealthcare providers hypnotic suggestions

are by-passed and for that moment, thepresent and the future are yet undefined.This is often the opposite of the patientsexpectancy. Namely, the past experiencesand the diagnosis create a fixed mentalimage that expects pain and limitation.

Explore some of the following practicesstrategies to increase movement and flexibity without effort and to increase joy. Use

Free Your Neck and Shoulders*

Push away from the keyboard and sit at the edge of the chair with your knees bent at right angles and your feet shoulder-width apart and flat on the floor. Do the following movements slowly. DoNOT push yourself if you feel discomfort. Be gentle with yourself.

Look to the right and gently turn your head and body as far as you can go to the right. When youhave gone as far as you can comfortably go, look at the furthest spot on the wall and remember that spot. Gently rotate your head back to center. Close your eyes and relax.

Reach up with your left hand; pass it over the top of your head and hold on to your right ear. Then, gently bend to the left lowering your elbow towards the floor. Slowly straighten up. Repeat for a few times feeling as if you are a sapling flexing in the breeze. Observe what your body is doing as it bends and comes back up to center. Notice the movements in your ribs, back and neck. Then, drop your arm to your lap and relax. Make sure you continue to breathe diaphragmatically throughout the exercise.

Reach up with your right hand and pass it over the top of your head and hold on to your left ear.Repeat as above except bending to the right.

Reach up with your left hand and pass it over the top of your head and hold on to your right ear.Then, look to the left with your eyes and rotate your head to the left as if you are looking behind you. Return to center and repeat the movement a few times. Then, drop your arm to your lap and relax for a few breaths.

Again, reach over your head with your left hand and hold onto your right ear. Repeat the same rotating motion of your head to the left except that your eyes look to the right. Repeat this a few times then, drop your arm to your lap and relax for a few breaths.

Reach up with your right hand and pass it over the top of your head and hold on to your left ear.Then, look to the right with your eyes and rotate your head to the right as if you are looking behind you. Return to center and repeat a few times. Then, drop your arm to your lap and relax for a few breaths.

Again, reach over your head with your right hand and hold onto your left ear. Repeat the same rotating motion of your head to the right except that your eyes look to the left. Repeat this a few times then, drop your arm to your lap and relax for a few breaths.

Now, look to the right and gently turn your head and body as far as you can go. When you can not go any further, look at that point on the wall. Did you rotate further than at the beginning of the exercise?

Gently rotate your head back to center, close your eyes, relax and notice the feeling in your neck,shoulders and back.

*This practice was adapted from a demonstration by Sharon Keane and developed by Ilana Rubenfeld (2000).


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your creativity and explore your own per-mutations of the practices. Observe how your mood improves and your energy increases when you play a childhood gameinstead of an equivalent exercise. For exam-ple, instead of dropping your hands to yourlap or stretching at the computer terminalduring a micro- or meso-break ii , go over toyour coworker and play pattycake. This isthe game in which you and your partnerface each other and then clap your handsand then touch each others palms. Do thisin all variations of the game.

For increased ROM in the shouldersexplore some of the following (rememberthe basics: diaphragmatic breathing, mini-mum effort, rapid release):

Ball Toss: a hand-sized ball that is easily squeezed is best for this exercise. Monitorrespiration patterns, and SEMG forearmextensors and/or flexors, and upper trapeziimuscles. Sit quietly in a chair and focus ona relaxed breathing rhythm. Toss the ball inthe air with your right hand and catch it

with your left hand. As soon as you catchthe ball, drop both hands to your lap. Tossthe ball back only when you achieve relax-ationboth with the empty hand and thehand holding the ball. Watch for over-efforting in the upper trapezii. Begin slowly and increase the pace as you train yourself to quickly release unnecessary muscle ten-sion. Go faster and faster (just about every-

one begins to laugh, especially each timethey drop the ball).Ball Squeeze/Toss: Expand upon the

above by squeezing the ball prior to tossing. When working with a patient, call out dif-ferent degrees of pressure (e.g., 50%, 10%,80%, etc.). The same rules apply as withthe ball toss.

Ball Hand to Hand: Close your eyes andhand the ball back and forth. Go faster and

faster and add ball squeezes prior to passingthe ball.

Gym Ball Bounces: Sit on a gym balland find your balance. Begin bouncingslowly up and down. Reach up and loweryour left then, right hand. Abduct yourarms forward then, laterally. Turn on theradio and bounce to music.

Simon Says: This can be done standing,sitting in a chair or on a gym ball. Whenon a gym ball, bounce during the game.Have your patient do a mirror image of your movements: reaching up, down, left,right, forward or backward. Touch yourhead, nose, knees or belly. Have fun and gomore quickly.

Summary:An Attitude of Fun

In summary, it is not what you do; it isthe attitude by which you do it that affectshealth. From this perspective, flexibility andmovement are enhanced, discomfortdecreased and health increased when exer-cises are performed with joy and experi-enced as fun. Inducing laughter promotes

healing and disrupts the automatic negativehypnotic suggestion/self-images of what isexpected. The patient begins to live in thepresent moment and thereby decreases theanticipatory bracing and dysponetic activity stirred-up by striving. By decreasing strivingand concern for results, patients may allow themselves to perform the practices with apassive attentive attitude that may facilitatehealing. For that moment the patient for-

gets the painful past and a future fraught with promises of continued pain and inac-tivity. Instead, the moment is lived in a joyful presentone in which the pain cycle iinterrupted and which can provide hopeand a glimpse into a healthy future.

ReferencesHanna, T. (1988). Somatics . Reading, MA:

Addison-Wesley.Kabat-Zinn, J. (1990). Full catastrophe living.

New York: Delacorte Press.Murphy, M. (1993). The future of the body.New

York: Jeremy P. Tarcher/PerigeePeper, E. (1990). Breathing for health with

biofeedback.Montreal: Thought Technology Ltd.Peper, E., Gibney, K. & Holt, C. (2002). Make

health happen: Training yourself to create wellnDubuque, IA: Kendall-Hunt.

Rubenfeld, I. (2000).The listening hands: Selfhealing through Rubenfeld Synergy method of touch.New York: Bantam Doubleday

Thayer, R.E. (1996). The origin of everyday

moodsManaging energy, tension, and stress.New York: Oxford University Press. Whatmore, G. and Kohli, D. The

Physiopathology and Treatment of Functional Disorders.New York: Grune and Stratton, 1974.

Footnotesi Dysponesis involves misplaced muscle

activity activities or efforts that are usuallycovert and, which do not add functionally to the movement. From: Dys meaningbad, faulty or wrong, and ponos meaningeffort, work or energy (Whatmore andKohli, 1974)

ii A meso-break is a 10 to 90 secondbreak that consists of a change in work position, movement or a structured activitysuch as stretching that automatically relaxthose muscles that were previously activat

while performing a task.


Back-To-Back MassageWith a partner stand back-to-back. Lean against each others back so that you provide mutual sup- port. Then each rub your back against eachothers back. Enjoy the wiggling movement and stimulation. Be sure to continue to breathe.


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heavily researched and is based on thepremise that an athletes performance suffers

when tension exceeds their capacity foroptimal functioning. This rather datedconcept is often referred to as the invertedU hypothesis (Yerkes & Dodson, 1908),

which basically contends that optimal ath-letic performance is found somewhere inthe midrange between calmness and ten-sion. In other words, performance willimprove with heightened arousal, but only up to a certain point, after which perform-ance will actually begin to deteriorate asarousal continues to increase. Students of economics may recognize a similarity between this theory and the law of dimin-ishing returns. While the inverted-Uhypothesis has been challenged and/orrefined over the years (Gould & Udry,1994), suffice it to say that exceptional per-formance corresponds with an optimal levelof pre-competition arousal (Spielberger,1989). The goal is to find this level in eachathlete, and then train them to reproduce itin competition. Hyperarousal suggests relax-ation strategies, whereas hypoarousal neces-sitates interventions aimed at energizing orpsyching up (Zaichkowsky & Takenaka,1993). Pinel and Schultz (1978) used sur-face electromyography (sEMG) to demon-strate not only how high levels of pre-competitive muscle tension can disruptathletic performance, but that BFB-assisted

relaxation can ameliorate this same arousal.Blais and Vallerand (1986) also found BFBeffective in reducing competitive arousal. Inshort, BFB in a variety of forms has beenfound empirically capable of transformingdebilitative anxiety into constructive energy that can maximize performance across a

wide variety of sports.The second key area in SPP centers

around optimizing autonomic control . Thisapproach is also geared to healthy athletes

whose performance is adversely affected by autonomic phenomena, such as HR, sweat,

hand/foot temperature, respiration, and thelike. The aim is to teach self-regulatory skills that enable the competitor to becomeaware of these physiological processes inorder to manipulate them to his or heradvantage. An example might be a biath-lete who is required to shoot a target afterskiing several kilometers at race-pace.

Because under those conditions heart rate(HR) is not just rapid but subjectively pal-pable, the athlete can learn where in eitherthe respiration or HR cycle to initiate theirshot in order to achieve maximal results. Insuch a situation, reduction of arousal is notimportant, because after shooting, the ath-lete must resume several kilometers of race-pace skiing. The competitor must thereforemaintain existing levels of arousal whilelearning to use proprioceptive cues as sig-nals for when to pull the trigger.

The third area of SPP research involvesrehabilitative interventions with injured ath-letes. Much of the work in this area centersaround physical therapy applications of electromyography (EMG).Chondromalacia, for example, can oftenresult from muscle imbalances reinforced by repetitive cycling or running. Concomitantpatellofemoral pain can actually be amelio-rated through differential strengthening of vastus medialis and vastus lateralis, twomuscles which can be neatly individuatedand retrained through EMG. This approach

was reported by Swanik, Lephart, Giraldo,Demont, & Fu (1999) in a study of femaleathletes with injuries to the anterior cruci-ate ligament (ACL). The authors deter-mined that sEMG made it possible todifferentially strengthen quadicreps andhamstrings to restore functional stability of the knee as well as protect it from subse-

quent ligamentous injury. A somewhat dif-ferent rehabilitative application involvedsEMG being used to encourage hamstringrelaxation in order to measure anterior tibialdisplacement in ACL-deficient patients, anotherwise difficult procedure (Feller, Hoser,& Webster, 2000). Other BFB modalitieshave also shown utility in sports medicine,e.g., Zaichkowsky and Fuchs (1988), whodiscuss applications of HR, blood flow, andrespiration feedback to limit, for example,the cardiorespiratory impact of rehabilita-tive exercise.

To summarize, SPP approaches can bedifferentially adapted for use with both dis-tressed and non-distressed athletes. Thethree major directions just identified in SPPhave been uniquely incorporated into a five-step schema that shows promise in regulat-ing HR, increasing flexibility and musclestrength, and/or reducing pain and fatigue

(Blumenstein, Bar-Eli, M., & Tenenbaum,1997).

Current IssuesDespite the potential for this field as sug

gested by the research cited above, severaltrends should be of some concern to BFB aa profession, and more specifically to SPP

a sub-discipline within the exercise scienceThe first observation in reviewing the literture is that notwithstanding the seemingimportance of psychophysiological variablin athletic performance, the literature in tharea is not nearly as prolific as one mightguess. Zaichkowsky and Fuchs (1988), twoof the more prolific researchers in this fieldreferred to the total number of SPP studiesas extremely limited. While BFB in geneal, unlike research in countless other areas psychology, may tend to be a rather esoteritopic by itself, studies that specifically focu

on BFB applications in sport are decidedlymore obscure. Such a literature search wouyield only a handful of studies, even fewer

when narrowing in on either a specific spo(e.g., BFB with cross country skiers) or aspecific BFB modality (EMG in sport). Tolook at both a specific sportand specificBFB modality (EMG with cross country skiers) may yield only a few studies at besdepending on the sport, sometimes none atall. In the preparation of this manuscript, arather extensive literature search yielded lethan 100 studies reporting on BFB applications of any kind in any sport between 197and 2001. Compare that 25 year period, foexample, to the 2700 or so studies on relaxation alone that were counted between 197and 1997 (Friedman, Sedler, Myers, &Benson, 1997) or to the 7000 studies in thefield of sport psychology that were pub-lished between 1971 and 1991 (Kunath,1995). The inference here is that, for what-ever reason, SPP may be a grossly under-researched area.

Perhaps even more striking is the paucitof SPP research published by the

Association for Applied Psychophysiologyand Biofeedback (AAPB), considered by many the official voice for BFB practitioners in the U.S. The present study foundthat over the ten years between March,1991 through September, 2001, the Journaof Applied Psychophysiology and Biofe


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(formerly calledBiofeedback and Self-Regulation) published only four articles that

were in any way related to this topic (vonScheele & von Scheele, 1999; Cassisi,Sexton-Radek, Castrogiovanni, Chastain, &Robinson, 1993; Nixon, 1994; Ceugniet,Cauchefer, & Gallego, 1994) with half of them appearing in just one issue. AAPBssister periodical,Biofeedback,over the sameten year period fared similarly, with only sixarticles addressing BFB in sport (Tremain,1996; Kall, 1997; Wilson & Gunkelman,2001; Sime, Allen, & Fazzano, 2001;Chartier, 2001; Carlstedt, 2002). Again,three of those articles (60%) appeared in

just one issue (Spring, 2001), an intriguingreflection of the lack of research in thisimportant area.

Another possible trend, as reflected by what this author gleaned from the availableresearch, is the possibility that professionalinterest in SPP might actually have declinedsomewhat over the past ten years. Althoughany effort to quantify this was beyond thescope of the present paper, fewer studiesmay have been published in recent years ascompared to what seemed like burgeoninginterest in the 1970s and 80s. This possibil-ity seems deserving of further investigation,particularly in light of continuously favor-able outcome studies. Also of interest(though not within the context of thispaper) is that while biofeedback research in

the sports sciences admittedly continues,much of the current work, unlike in thepast, may be occurring outside North

America. A final anecdote is that BFB research

involving traditional applications seems tobe increasingly supplanted by researchfocusing on neurofeedback (NF: Wilson &Gunkleman, 2001). In fact, the Spring2001 edition of Biofeedback devoted anentire issue to optimal functioning, andalthough that issue did include several arti-cles on BFB in motor skills development,

each was geared exclusively around neuro-feedback (NF), with almost no mention of EMG, HR, oxygen consumption (VO2),galvanic skin response (GSR), heart ratevariability (HRV), and thermal feedback,historically the gold standards in clinicalbiofeedback.

If in fact these are bonafide trends, sever-

al questions emerge, some of which will beaddressed in this review. Have traditionalBFB modalities in sport outlived their use-fulness? Does the paucity of empirical stud-ies in this field suggest that BFB in generallacks utility in the sports sciences? Are tra-ditional BFB approaches inherently flawed,or are we simply needing new moreportable technology that will make tradi-tional instrumentation less obtrusive andtherefore of greater utility to athletes andcoaches? Are there intrinsic methodological

weaknesses to SPP research, and if so how can we in the profession encourage moreempirical rigor so as to promote greatercredibility to BFBs role in sport. And,finally, we need to look at whether NF isactually becoming the preferred medium inSPP, or is this simply the prevailingGeist ?

SummaryIt should be clear from the above that

BFB has considerable potential to benefitathletes, particularly on the elite level.Moreover, the current literature review sug-gests that only a small part of this promisehas been realized thus far. In Part II of thisseries, we will explore traditional BFBmodalities (sweat, respiration, muscle tone,heart rate, etc.) and how they have already been adapted with varying degrees of suc-cess to a broad range of sports. Attention

will also be given to the importance of sound methodology as thesine qua nonforestablishing credibility in SPP research andpractice. In a subsequent issue, Part III willexamine future directions in this field by considering specific indices widely used inexercise physiology (cortisol, cate-cholamines, blood lactate, oxygen con-sumption, etc.) and their possible utility asBFB measures with athletes.

References Armstrong, L. (2000).Its not about the bike: My

journey back to life.New York: Putnam.Blais, M.R. & Vallerand, R.J. (1986).

Multimodal effects of electromyographic biofeed-back: looking at childrens ability to control pre-competitive anxiety. Journal of Sport Psychology,8,283-303.

Blumenstein, B., Bar-Eli, M., & Tenenbaum, G.(1997). A five-step approach to mental trainingincorporating biofeedback.The Sport Psychologist,11, 440-453.

Braden, V. (1985). Forward. In J.H. Sandweiss& S.L. Wolf (Eds.), Biofeedback and sports sciences .(p. x). New York: Plenum Press.

Carlstedt, R.A. (2002). Ambulatory psychophyiology and ecological validity in studies of sportsperformance: issues and implications for intervention protocols in biofeedback.Biofeedback,29(4),18-22.

Cassisi, J., Sexton-Radek, K., Castrogiovanni,M., Chastain, D., & Robinson, M. (1993). The usof ambulatory EMG monitoring to measure com-pliance with lumbar strengthening exercise.Biofeedback and Self-Regulation,18(1), 45-52.

Ceugniet, F., Cauchefer, F., & Gallego, J. (1994Do voluntary changes in inspiratory-expiratory ratio prevent exercise-induced asthma?Biofeedbacand Self-Regulation, 19(2), 181-188.

Chartier, D. (2001). Biofeedback and optimumperformance. Biofeedback , 29(1), 19- 22.

Collins, D. (1995). Psychophysiology and sporperformance. In S.J.H. Biddle (Ed.),EuropeanPerspective on Exercise and Sport Psychology.(pp.154-178). Champaign: Human Kinetics Press.

Feller, J., Hoser, C., & Webster, K. (2000).EMG biofeedback assisted KT-1000 evaluation oanterior tibial displacement.Knee Surgery in SpoTraumatology Arthroscopy , 8(3), 131.

Friedman, R., Sedler, M., Myers, P., & Benson,H. (1997). Behavioral medicine, complementary medicine and integrated care: economic implica-tions. Primary Care , 24, 949-962.

Gould, D. & Udry, E. (1994). Psychologicalskills for enhancing performance: arousal regulatstrategies. Medicine and Science in Sports and Exercise , 26(4), 478-485.

Kall, R. (1997). Optimal functioning training.Biofeedback , 25(4). 8-10.

Kunath, P. (1995). Future directions inexercise and sport psychology. . In S.J.H. Biddle(Ed.), European Perspective on Exercise and SpPsychology . (p. 329). Champaign: HumanKinetics Press.

Landers, D.M. (1985). Psychophysiological

assessment and biofeedback: applications for ath-letes in closed-skills sports. In J.H. Sandweiss &S.L. Wolf (Eds.),Biofeedback and Sports Scienc.(pp. 63-105). New York: Plenum.

May, M. (2000). The athletic arms race.Scientific American Presents,11(3), 74-79.

Nixon, P.G. (1994). Effort syndrome: hyperventilation and reduction of anaerobic threshold.Biofeedback and Self-Regulation, 19(2), 171-180.

Pinel, J. & Schultz, T. (1978). Effect of antecedent muscle tension levels on motor behavior. Medicine and Science in Sports and Exercis,10(3), 177-182.

Sandweiss, J.H. & Wolf, S.L. (1985),Biofeedbaand Sports Sciences . New York: Plenum.

Sime, W., Allen, T., & Fazzano, C. (2001).Optimal functioning in sport psychology: helpingathletes find their zone of excellence.Biofeedbac,29(1), 23- 25.

Spielberger, C.D. (1989). Stress and anxiety insports. In D. Hackfort & C.D. Spielberger (Eds.), Anxiety in Sports: An International Perspective(pp.3-17). New York: Hemisphere.


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Abstract: Since the discovery of photic driv-ing by Adrian and Matthews in 1934, muchhas been discovered about the benefits of brainwave entrainment (AVE) or audio visual entrainment (AVE) as it is commonly knowntoday. Studies are now available on the effec-tiveness of AVE in promoting relaxation, hyp-notic induction and restoring somatic homeostasis, plus improving cognition, and for treating ADD, PMS, SAD, migraine headache, chronic pain, anxiety, depressionand hypertension.

HistoryClinical reports of flicker stimulation

appear as far back as the dawn of modernmedicine. It was at the turn of the 20thcentury when Pierre Janet, at the SalptrireHospital in France, reported that when hehad his patients gaze into the flickeringlight produced from a spinning spoked

wheel in front of a kerosene lantern, it low-ered their depression, tension and hysteria(Pieron, 1982). Then, in 1934, Adrian andMatthews published their results showingthat the alpha rhythm could be drivenabove and below the natural frequency withphotic stimulation (Adrian & Matthews,1934).

This discovery further propagated a hostof small physiological outcome studies onthe flicker following response by many

well respected researchers (Bartley, 1934,1937; Durup & Fessard, 1935; Jasper,1936; Goldman, Segal, & Segalis, 1938;

Jung, 1939; Toman, 1941). Finally in 1956, W. Gray Walter published the results onthousands of test subjects comparing flickerstimulation with the subjective emotionalfeelings it produced (Walter, 1956).

Meanwhile, William Kroger accom-

plished other important developments inphotic stimulation. Kroger was a physicianinvestigating why radar operators weregoing into trances in front of their radarsets and of course, leaving the ship or planeat great risk to the enemy. He concludedthat the rhythmic blip of the radar waspulling the radar operators into a trancestate. These findings compelled Kroger toteam up with Sydney Schneider of theSchneider Instrument Company of Ohio toconstruct and market the first electronicclinical photic stimulator, called theBrainwave Synchronizer. It comprised anintense xenon strobe light complete with arotating dial that could be set to the fre-quencies of the standard four brain waverhythms. They found the BrainwaveSynchronizer had powerful hypnotic quali-ties and soon published a study on hypnoticinduction (Kroger & Schneider, 1959).They also prompted other studies involvinghypnotic induction in surgery and dentistry,and studies of general interest to the hypno-sis profession (Sadove, 1963; Margolis,1966; Lewerenz, 1963).

In 1981, Comptronic Devices Limited was incorporated, with a focus on designingTENS units and EMG feedback devices fordental (TMJ) applications. In 1984, Idesigned the Digital Audio-VisualIntegration Device (DAVID1), used for

hypnotic induction and to calm anxiety inperforming arts students at the University of Alberta. The light and sound (L&S)market at this time was in its infancy andresided primarily within the new age sector.There was little known research to sup-port L&S technology, and professionals by and large showed disinterest in L&S tech-nology. Due in part to poor quality L&S

products and a lack of research, about 40L&S companies have come and gone, moof them during the 1980s and 1990s.However, since the time of Adrian andMatthews, a considerable number of studihave verified photic and auditory drivingof the EEG. I have since re-named this phnomenon as audio-visual entrainment or

AVE, as any given frequency of stimulatiothat is reflected in brain wave activity andobservable on an EEG or QEEG can beentrained. Many more studies on photic orcombined audio/photic stimulation existthan pure audio stimulation studies, however audio-only stimulation studies have confirmed audio entrainment (Chatrian,Petersen, & Lazarte, 1959) and its effect ocalming masseter muscle tension (Manns,Miralles, & Adrian, 1981).

Physiology of Audio-Visual EntrainmentIn order for entrainment to occur, a con-

stant, repetitive stimuli of sufficientstrength to excite the thalamus must bepresent. The thalamus then passes the stimuli onto the sensory-motor strip, the cortexin general and associated processing areassuch as the visual and auditory cortexes.Figure 1 shows the visual pathway with thretina of both eyes becoming excited andsending pulses down the optic nerve,

through the optic chiasm, and into the lat-eral geniculate of both thalami. From herethe visual signals are passed onto the visuand cerebral cortexes for further processinNotice that there is very little delay fromthe onset of the flash to the response in thoptic nerve, but a delay of approximately 100 msec occurs by the time the visualevoked potential (VEP) is elicited in the

Audio-Visual Entrainment:

I. History and PhysiologicalMechanismsDavid Siever 1, Edmonton, Alberta, Canada

FEATURE ARTICLE

David Siever


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visual cortex. This delay may be why entrainment occurs best at thenatural alpha frequency as 100 msec equates to 10 Hz.

Photic entrainment begins its process as a series of overlappingevoked potentials (Kinney, McKay, Mensche, & Luria, 1973).Kinney broke down a simple VEP into its various components(Figure 2) representing the passage of time for 4, 8, 12 and 20 Hz.

As can be seen, much of the VEP occurs within 250 msec, correlat-ing to four Hz. The various overlapping parts were then vectorsummed into the mathematical VEP and compared with the actualVEPs observed by EEG at the higher, entrained frequencies, shownin Figure 2.

When this mathematical model was compared with the actualobserved EEG of the entrained stimuli (Figure 3), a high degree of predictability was observed, demonstrating that photic entrainmentis indeed a vector summation of VEPs and not a novel neuronalprocess.

By definition, entrainment occurs when an EEG reflects the brain wave frequency duplicating that of the stimuli, be it audio, visual ortactile (Siever, 2002). Entrainment occurs best near ones own natu-ral alpha frequency (Toman, 1941; Kinney et al., 1973). LEDs andxenon strobe lights contain much harmonic content due to thesquareness or rapid turn-on and turn-off transitions of the stimuliand these harmonics are reflected within the EEG. Figure 4 shows astrong and pure entrainment at 12 Hz. The harmonics (small

wavelets) seen in the EEG are a reflection of the actual harmonicscontained within the stimulus. Square wave stimulation is associat-ed with an increased risk of seizure (Joyce & Siever, 2000;Ruuskanen-Uoti, 1994). The only way to produce entrainment

without harmonics is via sine wave stimulation in which the stimuliturn on and turn off in slow, gentle transitions and do not containharmonics. (Van der Tweel, 1965; Townsend, 1973; Regan, 1966;Siever, 2002).

AVE at 18.5 Hz has also been shown to produce dramatic

increases in EEG amplitude at the vertex (Frederick, Lubar, Rasey,Brim, & Blackburn, 1999). The results of this study showed that:a) eyes-closed 18.5 Hz. photic entrainment increased 18.5 Hz

EEG activity by 49%.b) eyes-open auditory entrainment produced increased 18.5 Hz.

EEG activity by 27%.c) eyes-closed auditory entrainment produced increased 18.5 Hz

EEG activity by 21%.d) eyes-closed AVE produced increased 18.5 Hz. EEG activity by

38.3%.The bulk of entrainment shows itself near the vertex and frontally

(Siever, 2002). Figure 5 is a QEEG, or brainmap from the SKIL(Sterman-Kaiser Imaging Labs) database, in 1Hz bins showing the

frequency distribution of AVE at 7.8 Hz. N

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