altering the gag reflex via a palm pressure point

2008;139;1365-1372 J Am Dent Assoc

and Michael Hughes Donna Scarborough, Michael Bailey-Van Kuren

PointAltering the Gag Reflex Via a Palm Pressure

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The gag reflex is a highlyvariable protective reflexthat frequently interfereswith dental procedures.Typically, tactile stimula-

tion within five trigger zones—theanterior and posterior faucial pil-lars, the base of the tongue, thepalate, the uvula and the posteriorpharyngeal wall—will elicit the gagreflex.1 For some people, however,tactile stimuli more anterior to thetrigger zones, visual stimuli (suchas impression trays and spoons),auditory stimuli, olfactory stimuliand psychic stimuli (thinking abouta stimulus) also can trigger a gagreflex.2-4 In addition to the varioussensory input that can trigger a gagreflex, the type and the strength ofmotor response can differ within thegeneral population. The most rig-orous description of the motorresponse of the gag reflex is that itis a constriction of the pharynx.5,6 Amore traditional view of the gagreflex, however, is that it is a low-ering of the mandible in a forwardand downward trajectory, withvelar and pharyngeal constriction.7

And yet another description adds avocalization component to the tradi-tional view, thus blurring the differ-ence between a gag and a retch.8

Concomitant responses such asvomiting, nausea, and autonomicsigns and symptoms (for example,diaphoresis, lacrimation) also havebeen included in definitions of themotor component of the gag reflex.1

In addition to reports of differentdegrees of motor responses, gag

Dr. Scarborough is an assistant professor, Department of Speech Pathology and Audiology, Miami Uni-versity, 26 Bachelor Hall, Oxford, Ohio 45056, e-mail “[email protected]”. Address reprint requeststo Dr. Scarborough.Dr. Bailey-Van Kuren is an associate professor, Mechanical and Manufacturing Engineering, MiamiUniversity, Oxford, Ohio.Mr. Hughes is the manager, Statistical Consulting Center, and instructor, Department of Mathematicsand Statistics, College of Arts and Science, Miami University, Oxford, Ohio.

Altering the gag reflex via a palm pressurepointDonna Scarborough, PhD; Michael Bailey-Van Kuren, PhD; Michael Hughes, MS

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JADA, Vol. 139 http://jada.ada.org October 2008 1365

Background. The gag reflex regularly interfereswith dental procedures. The authors hypothesizethat applying pressure to a specific point on the palmalters the gag reflex and that hypersensitive gagreflexes may be categorized according to oropharyngeallandmarks.Methods. Thirty-six neurologically intact subjects underwent a seriesof gag reflex trials (baseline, sham and treatment). The authors devel-oped a hand pressure device for subjects to wear, which provided a con-sistent force, and they described a gag trigger point index (GTPI) scale.On the basis of the GTPI, they divided subjects into a hypersensitivegroup and an expected-sensitivity (control) group.Results. The trigger point of the gag reflex moved posteriorly in all sub-jects as a result of pressure to the palm point. Statistical results fromrepeated measures analysis of variance support the GTPI baseline data,and group assignments helped predict mean GTPI scores across condi-tions. The authors noted a significant treatment-group interaction effect,which indicated that the difference in mean GTPI responses between thehypersensitive and expected-sensitivity groups depended on the treat-ment being used.Conclusions. The authors introduce a treatment involving the stimu-lation of a pressure point that consistently altered the gag reflex trigger.The results of the study show the need for a more detailed, systematicapproach to studying the hypersensitive gag reflex.Clinical Implications. The change in trigger point in the hypersen-sitive group represented a functional gain. Application of the pressurepoint during dental procedures would decrease the likelihood of trig-gering a gag reflex.Key Words. Reflex; gag; acupressure; adult.JADA 2008;139(10):1365-1372.

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reflex strengths vary among people from absentto hyperactive.7,9,10

There is no clear definition of a hypersensitivegag reflex in a neurologically intact person.Instead, descriptions of a hyper gag reflex can bedivided into two categories: the force of the motorresponse and the place of sensory stimulation.The most common descriptions involve the forceof motor response. They include severely pullingaway from tactile stimulation,7 spasms of thepharynx1 or a combination of reflex responseswith both gagging and some aspect of the emeticresponse.1,3,6 A less common description of thehypersensitive gag reflex pertains to where thegag reflex is triggered. Historical reports of stub-born gaggers described people who triggered agag reflex in the anterior or middle portions of theoral cavity during toothbrushing or while shavingas a result of gagging caused by touch to theface.2,4 Recently, gag reflex responses to nonoralbody parts and regions within the anterior oralcavity have been documented in a group of chil-dren 3 to 18 months of age who had persistentfeeding delays.11

Attempts have been made to diminish the gagreflex within clinical settings. Early interventionsincluded swabbing patients’ mouths with dilutedcocaine; using distraction techniques; askingpatients to use willpower,2 excise their uvulas,3

voluntarily increase respiration9 and hold theirbreath3; hypnosis12; and relaxation withhypnosis.4 Behavior modification, suggestion, sys-tematic desensitization, sensory flooding andmedications also have been explored.1,3,13

Acupuncture points on the ear14 or forearm15 cancontrol the gag reflex effectively during dentaltreatments. In two 2005 articles, combinations ofacupuncture and hypnosis were recommended totreat a hypersensitive gag reflex during long-termtherapy.16,17 Although this combination treatmentmay alleviate a hyperactive gag reflex, complica-tions may arise, specialized training or teamswould be needed and the invasive nature of thetechnique is undesirable for many patients. Formost dentists and other medical practitioners, aless invasive approach such as acupressure wouldbe an attractive alternative. To our knowledge,only one brief clinical report has indicated that apressure point on the chin would be effective fordiminishing the gag reflex.18

One unpublished clinical technique used toremediate the hypersensitive gag reflex, whichwas used in the study population but not

reported, involved children with feeding delays(the population is described in detail in Scarbor-ough and colleagues11). The technique involvesthe use of a pressure point in the palm of thehand. This technique was being used in the field,but there was no research to substantiate its effi-cacy, and it was not derived from a known pres-sure point that was adapted for clinical use.

To better understand why this clinical tech-nique was successful in this group of children, wedeveloped an adult model. We conducted aninformal pilot study in three women and two menwho were reported to have a hypersensitive gagreflex and who had an intact neurological system.Four of the subjects were white, and one wasAfrican-American. We found normalization (thatis, triggering the gag reflex in the posterior por-tion of the oral cavity) in all of the subjects exceptfor the black man when pressure was applied to apoint in the palm of the hand.

This informal pilot study led to a second pilotstudy of seven healthy white women who had ahypersensitive gag reflex. We conducted thissecond study to develop consistent methodologicaltechniques to apply in a larger sample. Theresults of this study showed a normalization ofthe gag reflex (or movement of the gag behind theanterior faucial pillar) when we applied pressureto the palm of the right or left hand.

We conducted an exploratory study on thebasis of information we gleaned during these pilotstudies. The aims of this exploratory study, whichwe report here, were to establish that a handpressure point alters the trigger of the gag reflexin two groups of healthy adults and to introduce amethodological approach to evaluate the gagreflex on the basis of the location of sensory stim-ulation in the oral cavity.

SUBJECTS, MATERIALS AND METHODS

Hand pressure device. A hand pressure devicewas designed at Miami University, Oxford, Ohio,for this study, specifically to apply two pounds offorce to a specific pressure point on the palm ofthe hand. The device was modified from a handsplint that provided stiff support to the palm sideof the hand and equally spaced the digits. Thehand pressure device was secured to the hand viastraps. A hole was cut in the palm of the device toallow an actuating cylinder to press against thepalm of the hand, and the design allowed the

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1366 JADA, Vol. 139 http://jada.ada.org October 2008

ABBREVIATION KEY. GTPI: Gag trigger point index.


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actuating cylinder to be removed easily.These hand pressure devices were fab-ricated for both the right and lefthands. The force was applied by meansof a voice coil actuator with a three-quarter-inch–diameter circular padthat contacted the palm of the hand.This device was powered by a bipolaroperational power supply/amplifier,which allowed for manual and variablecontrol of the force applied to the sub-ject’s hand.

Gag response sensor probe. Asensor probe with a bend sensor poten-tiometer was developed at Miami Uni-versity to record the amount of pres-sure applied to the anatomicalstructures that elicited the gagresponse. As the probe contacts theinner surface of the oral cavity, theprobe bends the flexible sensor andgenerates a change in theoutput voltage, which isrecorded by a desktop com-puter. The probe sensorhas a light attached to theend for more accurateidentification of the struc-tures that are stimulated,as well as a time stamp.

Subjects. All of thesubjects were college stu-dents who volunteered torespond to a flier recruit-ing people with a self-perceived normal or hyper-sensitive gag reflex. Wescheduled subjects for asingle session in late morning or during the after-noon to avoid any influence that time of daymight have on the gag reflex.1 We screened allvolunteers for overt neurological difficulties. Weexcluded them if we observed gait difficulties,tremors, physical asymmetries, abnormal voicequalities, or speech or language disturbances. Wealso excluded volunteers if they reported having ahistory of neurological difficulties.

Forty-one subjects initially participated in thestudy. All of the subjects but two were white.Subjects were placed into two groups according tobaseline scores (Table 1). The hypersensitivegroup consisted of four women and three menwith a mean age of 18.8 years (standard deviation

[SD] = 0.35). The expected-sensitivity (control)group consisted of 20 women and 14 men with amean age of 20.0 years (SD = 2.65). Five subjects(four women and one man) in the expected-sensitivity group were unable to continue thestudy past the baseline data collection because weobserved no motor response bilaterally with stim-ulation of the posterior pharyngeal wall. Descrip-tive statistics for GTPI scores excluding these fivesubjects across the experimental treatmentsappear in Table 2.

The Institutional Review Board of Miami Uni-versity approved this study. We used universalprecautions for infection control in all subjects.

Once subjects signed an informed consent

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TABLE 1

Description of baseline gag trigger pointindex (GTPI) score coded by location in oralcavity where gag reflex is elicited, withnumber of subjects in each category.LOCATION OF GAG TRIGGER POINT GTPI SCORE NO. OF SUBJECTS

Posterior Pharyngeal Wall, NoMotor Response

0 5

Posterior Pharyngeal Wall, MotorResponse

1 4

Between Posterior Faucial Pillarsand Posterior Pharyngeal Wall

2 2

Posterior Faucial Pillars 3 6

Between Anterior Faucial Pillarsand Posterior Faucial Pillars

4 11

Anterior Faucial Pillars 5 6

Between Second Molars and Anterior Faucial Pillars

6 4

Second Molars 7 3

Internal Cheek, Center 8 0

TABLE 2

Comparison of gag trigger point index data betweenthe hypersensitive group and the expected-sensitivitygroup.GROUP STIMULUS

SIDEGAG TRIGGER POINT INDEX SCORE

BaselineMean (SD*)

Sham Mean(SD)

Left HandMean (SD)

Right HandMean (SD)

Hypersensitive(n = 7)

Right 5.86 (1.70) 5.86 (1.70) 2.29 (1.70) 2.57 (1.72)

Left 5.71 (0.95) 4.86 (1.10) 1.71 (0.95) 2.29 (1.60)

Expected-Sensitivity (n = 29)

Right 3.07 (1.46) 2.50 (1.32) 0.96 (0.92) 1.10 (0.86)

Left 3.14 (1.33) 2.72 (1.33) 0.79 (0.68) 0.83 (1.10)

* SD: Standard deviation.


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form, we explained the basic procedures to themand asked them to remove all watches, rings andbracelets. The subjects then underwent a series ofgag reflex tests: baseline, sham and treatment.

Baseline trials. We elicited one gag reflexfrom the left side of a subject’s oral cavity and onefrom the right side of the oral cavity in randomorder. We did not apply treatment. We providedsubjects with breaks of at least one minutebetween the two trials. Throughout this study,the minimal acceptable motor response to inputfrom the gag response sensor probe included con-striction of the pharynx and velum.5,6 The point inthe mouth (the anatomical marker) at which eachsubject gagged during these two trials was deter-mined by means of a gag trigger point index(GTPI) and served as baseline data. The GTPI isan ordinal index in which the oropharyngealregions are divided according to anatomical land-marks and assigned a score (an integer valuefrom 0 to 8) (Figure 1 and Table 1). All of thestimulation to elicit the gag reflexes began from ahigh GTPI area (the internal cheek) to a lowGTPI area (the pharyngeal wall). Once a subjectelicited a gag response, we stopped the trial anddid not test any more-posterior positions. To dif-ferentiate responses that occurred at the posteriorpharyngeal wall (gag response elicited versus nomotor response), we assigned two potential values(1 or 0) to this point. If a subject scored a 0 forboth sides of the intraoral cavity, we terminatedthe trial. We adapted this severity rating scale

from our second pilot study.The sole determiner of

group classification(expected-sensitivity orhypersensitive) for thisstudy was the baselinedata. We placed subjectswho gagged at stimulationof structures in front of theanterior faucial pillar(GTPI score ≥ 6) on at leastone side during baselinedata collection into thehypersensitive group. Theother subjects were placedin the expected-sensitivitygroup.

Sham trials. Once wecompleted the baselinetrials, we elicited two gagresponses as part of a sham

condition. All subjects were told that the shamtrials were related to over-the-counter antinauseabracelets that may be effective in minimizing thegag response. An adjustable bracelet was fas-tened lightly around a randomly selected wrist.We also randomized the order (right first or leftfirst) in which the oral cavity was stimulated. Weprovided breaks of at least one minute betweentrials. The point in the mouth at which stimula-tion elicited a gag reflex during the two shamtrials was scored according to the GTPI (Table 1).

Treatment trials. The pressure point we usedwas located in the middle of the palm at the angleof intersection of the thumb and third digit(Figure 2). We marked the subjects’ hands at thisintersection with a felt-tip marker. We placed theforce actuator of the hand pressure device overthe marked point on a randomly selected hand(right or left). Once the hand pressure device wassecured, subjects were instructed not to resist thepressure applied to the hand while the primaryinvestigator manually increased the force of theactuator to two pounds. This pressure thresholdis based on methods used in our second pilotstudy in which pressure was applied to thepalm.19 Unlike the sham trials in which the sub-jects were led to believe that the bracelet waseffective, we gave them no information about thetreatment trials. If a subject asked, we minimizedthe response (for example, stating “We’re justtrying this out”). We then elicited gag responses,one on the right side of the intraoral cavity and

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Posterior Pharyngeal Wall

Posterior FaucialPillars

Anterior Faucial Pillars

(Palatoglossal Arch)Second Molars

Internal Cheek

Figure 1. Photograph of oral cavity showing key landmarks of the gag trigger point index. Photograph courtesy of D.B. Fankhauser, University of Cincinnati.


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one on the left side, in random order. We thenused the hand pressure device on the alternatehand and followed the same procedures. We pro-vided breaks of at least one minute betweentrials, and we provided a longer break if the sub-ject requested it.

At completion of the study, we gave each sub-ject a debriefing statement addressing the decep-tion component of the sham trials in compliancewith the Miami University Institutional ReviewBoard guidelines.

Statistical analysis. We analyzed the data byusing repeated measures analysis of variance(ANOVA) of a mixed effect model fit to the experi-mental GTPI scores. This type of model allows forassessment of effects of between-subjects factorsand within-subjects factors, and it accommodatespotential correlation amongmeasurements made inthe same subject.20,21

Between-subjects factorswere group (hypersensitiveor expected-sensitivity, asdetermined from baselinetrials) and sex (male orfemale). Within-subjectsfactors were experimentaltreatment (sham, left handpressure device or righthand pressure device) andstimulus side (left orright). We constructedfollow-up contrasts to assess group discrepanciesin mean GTPI score between pairs of treatments.We checked and verified assumptions regardingnormality of residual distributions. We performedall analyses by using statistical software (PROCMIXED, Version 9.1 for Windows, SAS, Cary,N.C.).

RESULTS

For all subjects in both groups, the gag reflexmoved posteriorly toward the pharyngeal wallafter application of pressure to this point. We con-ducted a preliminary assessment that confirmedthat there were no significant changes in meanGTPI score differences between the baseline andsham trials after adjusting for sex and stimulusside (F = 0.81, numerator degrees of freedom = 1,denominator df = 33, P = .3741). We then per-formed repeated-measures ANOVA on the treat-ment trial data to investigate the effect of thetreatments on mean GTPI scores. We tested the

high-order interactions between experimental fac-tors iteratively, and we found that they were notsignificant, resulting in the reduced model resultspresented in Table 2. We checked and verifiedassumptions of residual normality and constantvariance.

ANOVA results revealed a significant sex-group interaction in determining mean GTPIscores regardless of treatment (Table 3). In thehypersensitive group, women had an overallmean GTPI score of 2.58 (SD = 2.12), and menhad an overall mean GTPI score of 4.17 (SD = 1.50). In the expected-sensitivity group,women had an overall mean GTPI score of 1.46(SD = 1.38), and men had an overall mean GTPIscore of 1.52 (SD = 1.31).

The analysis supports the finding that theGTPI baseline data and group assignments canbe used to predict mean GTPI scores across condi-tions. We noted a significant treatment-groupinteraction effect, indicating that the difference

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Figure 2. Photograph of palm pressure point.

TABLE 3

Repeated-measures analysis of variance test resultsfor fixed effects.EFFECT NUMERATOR

DEGREES OFFREEDOM

DENOMINATORDEGREES OFFREEDOM

F VALUE P VALUE

Stimulus Side of Oral Cavity 1 32 3.57 .0678

Sex 1 32 11.65 .0018

Treatment 2 32 81.14 < .0001

Group 1 32 46.34 < .0001

Sex-Group Interaction 1 32 11.72 .0017

Treatment-Group Interaction

2 32 8.77 .0009


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between mean GTPI responses for the hypersen-sitive group and expected-sensitivity groupdepended on the treatment being used. Becauseof this interaction, we determined that assess-ments of group effects must be made according totreatment, and that the stimulus side was not asignificant factor in determining mean GTPI.

To further investigate the treatment effect inboth groups of subjects, we constructed statisticalcontrasts to compare group discrepancy in meanGTPI between all pairs of trials. These resultsappear in Table 4, and Bonferroni-adjusted P

values are provided. Discrepanciesbetween the groups were statisti-cally similar in left hand pressuredevice and right hand pressuredevice trials. The pairwise trialcontrasts that compared group dis-crepancy in mean GTPI betweenthe sham trial and a treatmenttrial (left hand pressure device orright hand pressure device) pro-duced statistically lower GTPIscores for treatment trial (P < .05).

DISCUSSION

To our knowledge, this study wasthe first of its kind to documentthat the application of pressure tothe center of the palm moves thetrigger point of the gag reflex. Forall subjects in both groups, the gagreflex moved posteriorly toward thepharyngeal wall after applicationof pressure to this point. Althoughall subjects demonstrated a changein the trigger of the gag reflex, thesubjects in the hypersensitivegroup demonstrated a statisticallysignificant degree of movementaccording to the GTPI areas com-pared with the subjects in theexpected-sensitivity group. Thechange in trigger point in the sub-jects in the hypersensitive grouprepresents a functional gain. Appli-cation of pressure to the center ofthe palm during dental procedureswould make triggering a gag reflexless likely (Figure 3).

The trigger points in theexpected-sensitivity group alsomoved to the posterior pharyngeal

wall for at least one of the treatment trials. Thisfinding was important because nine subjects inthe expected-sensitivity group reported a self-perceived heightened gag reflex sensitivity duringthe initial interview, and the palm pressure pointwas effective in this group.

Finally, we found a statistically significant sex-group interaction in the hypersensitive group thatwe did not see in the expected-sensitivity group,and it does not appear to be the result of a smallsample size. We found that gag reflexes in themen in the hypersensitive group were stimulated

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TABLE 4

Group discrepancies in mean gag triggerpoint index scores between pairs of trials.PAIRWISETRIAL COMPARISON

NUMERATORDEGREES OFFREEDOM

DENOMINATORDEGREES OFFREEDOM

F VALUE ADJUSTED P VALUE*

Sham VersusLeft Hand PressureDevice

1 32 17.46 .0006

Sham VersusRight Hand PressureDevice

1 32 12.20 .0036

Left Hand PressureDevice VersusRight HandPressureDevice

1 32 2.50 .3705

* All P values are Bonferroni-adjusted.

Hypersensitive Expected-Sensitivity7

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Figure 3. Mean hypersensitive and expected-sensitivity group gag trigger point indexscores, by order of application. Error bars represent plus or minus one standard error ofthe mean.


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significantly more anteriorly than were gagreflexes in women in the hypersensitive group. Itis not clear at this time why males in the hyper-sensitive group tend to react to more anteriorstimulation and why this same sex difference isnot seen in the expected-sensitivity group.

To our knowledge, our study also was the firstto categorize subjects with a hypersensitive gagreflex on the basis of the location of the trigger ofthe gag reflex rather than on the strength ofmuscle contraction. We divided subjects into thetwo groups according to our understanding of theafferent component of the gag reflex. Previousstudy results indicated that a typical gagresponse is triggered in the posterior one-third ofthe oral cavity within one of five trigger zones.1

This region is innervated by the glossopharyngealnerve, which is the afferent limb for the gagreflex. In our study, however, subjects in thehypersensitive group gagged when they receivedstimulation in more anterior regions. Thus, theseven subjects in the hypersensitive group repre-sented a neurologically abnormal or unexpectedgroup. Furthermore, our choice of the criteriaused to distinguish the two groups was supportedstatistically (Tables 3 and 4).

The subjects in the hypersensitive group camefrom the general population and were otherwiseneurologically intact. However, it seems unlikelythat the observed differences in the location of thetrigger of the gag reflex relate to anatomical vari-ations of the glossopharyngeal nerve. Consideringthat the hypersensitive group constituted 17 per-cent of the subjects recruited for our study, weexpected to find literature regarding this possi-bility. To our knowledge, however, no literaturein neurosurgery, otolaryngology, anatomicalreview or dentistry supports this idea.

Another explanation may be derived from ahypothetical model that has been proposed toexplain similar response patterns in a group oforally deprived infants.22 On the basis of thistheory, transient tactile connections between thetouch sensory fiber tracts and the nucleus tractussolitarius are present at birth via an inhibitoryconnection. Furthermore, the activity of the tran-sient fibers diminishes shortly after birth. In theaberrant or hypersensitive gag situation, thesetransient fibers fail to retract and consequentlyresult in continued stimulation of the nucleustractus solitarius with touch to areas other thanthe posterior one-third of the oral cavity.22 We donot know if this model can apply to the neurologi-

cally intact subjects in the hypersensitive group,nor do we understand the exact neurologicalmechanism of the hand pressure point’s influ-encing the gag reflex. Animal research is beingconducted to identify and map the specificpathway of the gag reflex, and it includes discov-ering the underlying neurochemical substratesinvolved23 and understanding the neurologicalmechanisms and anatomical regions involvedwith the hand pressure point.

Another facet we targeted specifically for thisstudy involved the purposeful use of light touchfor the sham trials and firm pressure for thetreatment trials. We carefully selected these twomethods because in many people light touch fol-lows a different neurological pathway than doesfirm pressure. Furthermore, at the skin level, dif-ferent sensory receptors are responsible for trans-mitting light touch versus firm pressure.Research is being conducted in rats to determinethe exact neurological mechanisms within thebrain stem for these two tactile sensory systems.

Another aspect of the study that needs furtherdiscussion is a potential order effect (Figure 3).Some may argue that with repeated stimulationof the gag reflex in a person, the gag reflex wouldbecome extinct or fatigued. The results in ourstudy were solely manifestations of an ordereffect. However, we provided subjects with breaksof at least one minute between the trials, whichshould have been sufficient time for the strengthof the contraction to return to the baseline state.24

Another argument regarding our findings maybe related to distraction. One might argue thatapplication of pressure to the palm of the handwould cause a person to be distracted from thegag reflex trials. However, we conducted andmanipulated the sham trials in a way that con-vinced subjects that a change in the gag reflexwould occur. We did not observe significantchanges in the gag trigger point with the shamtrial. Also, if distraction were the underlying phe-nomenon that reduced the gag reflex, one wouldpredict the gag reflex would return to baselinevalues across the four trials—baseline, sham, lefthand pressure device and right hand pressuredevice—as the subjects became accustomed to theprocedures.

In future studies, we will randomize the orderof the sham and treatment trials to enhance themethodology of the study. For this preliminarystudy, however, we tried to design a study thatwould give subjects every opportunity to cogni-

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tively control the gag reflex, and we led them tobelieve that the sham trial would be effective. Wealso designed the study so we could beginexploring the premise that with increased subjectexpectation we would have an increased ability tocognitively manipulate or alter the gag reflex.Thus, we made every effort during the shamtrials to compare the antinausea bracelet used inour study to over-the-counter antinausea wrist-bands with which many subjects were familiar.We wanted the subjects to believe that this lighttouch technique worked because we thought thatsubjects’ expectation was an important idea tobuild into the study.

CONCLUSIONS

The results of our study are preliminary andimply that a larger, randomized study is neededto statistically analyze any trends that affectdirect clinical applications. Basic characteristicssuch as sex, age, handedness, ethnicity and asso-ciated behaviors or patterns require furtherexploration. Future study should investigate sub-jects’ self-perceptions about the gag reflex andinclude the development of a severity scale. In ourstudy, nine subjects in the expected-sensitivity

group and the seven subjects in the hypersensi-tive group had a self-perceived hypersensitive gagreflex, but we did not explore the strength of themotor response of the gag reflex. A better under-standing of subjects’ perceptions and a detailedseverity rating scale may help us better under-stand the trigger zones and the strength of themotor response. ■

Disclosures. None of the authors reported any disclosures.

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