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Fig.13.11a,bRelationofmagnetoencephalographyactivityintheprimarygustatorycortexandperceivedintensitytovariousconcentrations
oftastestimulation.
aTheamplitude(circle)ofequivalentcurrentdipole(ECD)increaseswithincreaseinsodiumchlorideconcentrationfrom30mMto1M,but
theonsetlatency(square)doesnot.Tastestimuluswaspresentedtothetipofthetongue.
bPsychologicalperceivedintensityevaluated in the same experimentalso increases with increases intastantconcentration. Psychological
perceivedintensitywasmeasuredusingvisualanalogscalefrom0to5.
Fig. 13.12a, b Location of the primary gustatory cortex (PGA) revealed by functional magnetic resonance imaging (fMRI) (a) and
magnetoencephalography (MEG) (b). Yellow regions indicate taste-activated areas. In the fMRI study, a short pulse of sodium chloride
solutionwasrepetitivelyappliedtothetonguetipofparticipantsduringthestimulationperiod.Arrowsindicatethecentralsulcus.
Fig.13.13a–dAttenuationof3-Tmagneticresonancesignalsintheorbitofrontalcortex.Upperandlowerlinesofimagesindicateanatomical
(T2-weightedimages)andfunctionalimages(echoplanarimages)obtainedfromthehorizontalplanethroughthelines(a–d)shownattheleft
sagittal section. Lines (A–C) run through the orbitofrontal cortex (OFC), but (D) does not. Yellow masked areas in anatomical images
demonstratetheareasinwhichnoorfeeblemagneticresonancesignalwasdetectedinechoplanarimages.Thus,therostromedialpartofthe
OFCis“signalblackout”becauseoftheheterogeneityofmagneticsusceptibilitycausedbytheparanasalcavity.
LateralityofthegustatorypathwayfromthetonguetothePGAinhumanshasbeendebatedforalong
time. It is still a matter of ongoing controversy, having been reported as being ipsilateral,
66
contralateral,
67
and bilateral.
68
Experiments using patients withunilaterally transected chorda tympani
duringmiddleearcholesteatomaoperationshaverevealedthatunilateral(right-sided)stimulationevoked
bilateralcorticalactivationinthePGAwithashortlatencydifferencebetweenthetwohemispheres,
69
suggestingbilateralneuralprojectioninhumans.
HigherOrderCortex
Many fMRI and PET studies reported gustatory activation in cortices in peri-insular regions, frontal
operculum,orbitofrontalcortex,theamygdala,andcingulategyrus.Inparticular,theorbitofrontalcortex
isrelatedtohigherordertastefunctionssuchasfoodreward,
70,71
palatability,
72
sensory-specificsatiety,
73
and integration with olfaction.
74,75
In fMRI measurement using echo planar methods, however, the
heterogeneity ofmagnetic susceptibility causedbythe paranasalcavitystronglyattenuates themagnetic
resonancesignal
76
fromtherostralandmedialpartoforbitofrontalcortex,asshowninFig.13.13.The
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amygdala has been referred to as the region related to hunger or satiety,
77
food reward, or valence
(palatability).
78
The neural mechanism for taste intensity evaluationis unknown, even thoughthis is a fundamental
function of food evaluation. As described above, psychological perceived intensity had a partial
discrepancy with cortical activation in PGA when the tastantwas presented to the tip of participant's
tongue. Correlation analysis of psychological intensity and the whole amplitude of magnetic field
revealed that three latency periods from stimulus onset are significant in the process of intensity
evaluation.Dipole analysisrevealed thatthePGAwas observedinthefirstactivation(shortestlatency
~150 milliseconds), the hippocampus and cingulate gyrus in the second latency (~400 milliseconds)
simultaneously,and,again,thePGAandmidfrontalgyrusforthelastlatency(~800milliseconds).
79
These
resultsshowthatlotsofcorticalareasaredynamicallyrelatedtothesimpleintensityevaluationoftaste.
Otherhighertastefunctions,suchasreward,palatability,memory,andintegration,arealsosupposed
to be developed by such dynamic cortical networks. The role of cortical networks in such function
remainstobestudied.
Locationoftheprimarygustatorycortexwassuggestedtobethetransitionareabetweentheparietal
operculum andposterior partofthe insula.Thefrontal operculum,orbitofrontalcortex,amygdala,
andcingulategyruswouldberelatedtohigherfunctionssuchasfoodreward,palatability,sensory-
specificsatiety,orintegrationwitholfaction.
References
1. Snyder DJ, Prescott J, Bartoshuk LM. Modern psychophysics and the assessment of human oral sensation. Adv Otorhinolaryngol
2006;63:221–241
2.KroezeJHA.Istastemixturesuppressionaperipheralorcentralevent?In:LaingDG,CainWS,McBrideRL,AcheBW,eds.Reception
ofComplexSmellsandTastes.Sydney:Academic;1989:225–243
3.YamaguchiS.Thesynergistictasteeffectofmonosodiumglutamateanddisodium5′inosinate.JFoodSci1967;32:473–478
4.VonBekesyG.SensoryInhibition.Princeton:PrincetonUniversityPress;1967
5.OgawaH.Tasteandsmell.In:OzawaS,FukudaK,eds.StandardTextbookofPhysiology.7thed.Tokyo:Igakushoin;2009:294–302[in
Japanese]
6.MurrayRC. The ultrastructure oftaste buds. In: Friedmann I,ed. The Ultrastructure ofSensoryOrgans. Amsterdam: North Holland
PublishingCompany;1973:1–81
7.MiuraH,KusakabeY,HaradaS.Celllineageanddifferentiationintastebuds.ArchHistolCytol2006;69(4):209–225
8.BeidlerLM,SmallmanRL.Renewalofcellswithintastebuds.JCellBiol1965;27(2):263–272
9. Hamamichi R, Asano-Miyoshi M, Emori Y. Taste bud contains both short-lived and long-lived cell populations. Neuroscience
2006;141(4):2129–2138
10.WittM,ReutterK,MillerIJJr.Morphologyoftheperipheraltastesystem.InDotyRL,ed.HandbookofOlfactionandGustation.2nded.
NewYork:MarcelDekker,Inc;2003:651–677
11. Miller IIJr, Bartoshuk LM. Tasteperception, taste buddistribution, andspatial relationships. In:GetchellTV,BartoshukLM,DotyRL,
SnowJBJJr,eds.SmellandTasteinHealthandDisease.NewYork:RavenPress;1991:205–233
12. DotyRL,Bagla R,MorgensonM, Mirza N. NaClthresholds: relationshipto anterior tongue locus,area ofstimulation, andnumber of
fungiformpapillae.PhysiolBehav2001;72(3):373–378
13.BealerSL,SmithDV.Multiplesensitivitytochemicalstimuliinsinglehumantastepapillae.PhysiolBehav1975;14(6):795–799
14.BachmanovAA,BeauchampGK.Tastereceptorgenes.AnnuRevNutr2007;27:389–414
15.ChandrashekarJ,HoonMA,RybaNJP,ZukerCS.Thereceptorsandcellsformammaliantaste.Nature2006;444(7117):288–294
16.NikiM,YoshidaR,TakaiS,NinomiyaY.Gustatorysignalingintheperiphery:detection,transmission,andmodulationoftasteinformation.
BiolPharmBull2010;33(11):1772–1777
17. Huang YA, Dando R, Roper SD. Autocrine and paracrine roles for ATP and serotonin in mouse taste buds. J Neurosci
2009;29(44):13909–13918
18. Tomchik SM, Berg S, Kim JW, Chaudhari N, Roper SD. Breadth of tuning and taste coding in mammalian taste buds. J Neurosci
2007;27(40):10840–10848
19. Vandenbeuch A, Tizzano M, Anderson CB,Stone LM, GoldbergD,KinnamonSC. Evidence for a role of glutamate as an efferent
transmitterintastebuds.BMCNeurosci2010;11(77):77
20. Bartoshuk LM, Rennert K, Rodin J, Stevens JC. Effects of temperature on the perceived sweetness of sucrose. Physiol Behav
1982;28(5):905–910
21.YamashitaS,SatoM.Theeffectsoftemperatureongustatoryresponseofrats.JCellPhysiol1965;66(1):1–17
22.DamannN,VoetsT,NiliusB.TRPsinoursenses.CurrBiol2008;18(18):R880–R889
23.OzekiM.Conductancechangeassociatedwithreceptorpotentialsofgustatorycellsinrat.JGenPhysiol1971;58(6):688–699
24.KinnamonSC,RoperSD.Passiveandactivemembranepropertiesofmudpuppytastereceptorcells.JPhysiol1987;383:601–614
25.PritchardTC,NorgrenR. Gustatory system.In:PaxinosG, MaiJK,eds. The HumanNervous System.2nded.Amsterdam: Elsevier;
2004:1171–1196
26.IggoA,LeekBF.Theafferentinnervationofthetongueofthesheep.In:HayashiT,ed.OlfactionandTasteII.Oxford:PergamonPress;
1967:493–507
27.FrankME.Ananalysisofhamsterafferenttastenerveresponsefunctions.JGenPhysiol1973;61(5):588–618
28.SatoM,OgawaH,YamashitaS.Responsepropertiesofmacaquemonkeychordatympanifibers.JGenPhysiol1975;66(6):781–810
29. Sato M, Ogawa H, Yamashita S. Gustatory responsiveness of chorda tympani fibers in the cynomolgus monkey. Chem Senses
1994;19(5):381–400
30. HellekantG,Danilova V,Ninomiya Y. Primatesense oftaste: behavioralandsingle chordatympani andglossopharyngeal nerve fiber
recordingsintherhesusmonkey,Macacamulatta.JNeurophysiol1997;77(2):978–993
31.SatoM,YamashitaS,OgawaH.Potentiationofgustatoryresponsetomonosodiumglutamateinratchordatympanifibersbyadditionof
5′-ribonucleotides.JpnJPhysiol1970;20(4):444–464
32. Harada S, Yamamoto T, Yamaguchi K, Kasahara Y. Different characteristics of gustatory responses betweenthe greater superficial
petrosalandchordatympaninervesintherat.ChemSenses1997;22(2):133–140
33.ShingaiT.Waterfibersinthesuperiorlaryngealnerveoftherat.JpnJPhysiol1980;30(2):305–307
34.OgawaH,YamashitaS,NomaA,SatoM.Tasteresponsesinthemacaquemonkeychordatympani.PhysiolBehav1972;9(3):325–331
35.Nasse J,TermanD,VenugopalS,HermannG, RogersR,TraversJB.Localcircuitinputtothe medullaryreticular formationfrom the
rostralnucleusofthesolitarytract.AmJPhysiolRegulIntegrCompPhysiol2008;295(5):R1391–R1408
36. RollsTE,ScottTR. Central taste anatomy andneurophysiology. In: DotyRL,ed.Handbook ofOlfaction andGustation.2nd ed. New
York,Basel:MarcelDekker,Inc;2003:679–704
37.OgawaH,ImotoT,HayamaT.Responsivenessofsolitario-parabrachialrelayneuronstotasteandmechanicalstimulationappliedtothe
oralcavityinrats.ExpBrainRes1984;54(2):349–358
38. Hayama T, Ito S,Ogawa H. Responses of solitarytract nucleus neurons to taste and mechanical stimulations of the oral cavity in
decerebraterats.ExpBrainRes1985;60(2):235–242
39.VanBuskirkRL,EricksonRP.OdorantresponsesintasteneuronsoftheratNTS.BrainRes1977;135(2):287–303
40.HayamaT,HashimotoK,OgawaH.Anatomicallocationofataste-relatedregioninthethalamicreticularnucleusinrats.NeurosciRes
1994;18(4):291–299
41.OgawaH,NomuraT.Responsepropertiesofthalamocorticalrelayneuronsresponsivetonaturalstimulationoftheoralcavityinrats.Ann
NYAcadSci1987;510:532–534
42. Nomura T, Ogawa H. Thetasteandmechanicalresponse properties ofneuronsin theparvicellular partofthe thalamicposteromedial
ventralnucleusoftherat.NeurosciRes1985;3(2):91–105
43. Burton H,Benjamin RM. Central projections of the gustatory system. In: Beidler LM, ed. Handbook ofSensoryPhysiologyVol. IV
ChemicalSenses2,Taste.Berlin:Springer-Verlag;1971:148–164
44.OgawaH.Gustatorycortexofprimates:anatomyandphysiology.NeurosciRes1994;20(1):1–13
45. Sanides F. The architecture of the cortical taste nerve areas in squirrelmonkey (Saimirisciureus) and their relationships to insular,
sensorimotorandprefrontalregions.BrainRes1968;8(1):97–124
46. Cipolloni PB, Pandya DN. Cortical connections of the frontoparietal opercular areas in the rhesus monkey. J Comp Neurol
1999;403(4):431–458
47. Baylis LL, Rolls ET, Baylis GC. Afferent connections of caudolateral orbitofrontal cortex taste area of the primate. Neuroscience
1995;64(3):801–812
48.OgawaH,IfukuH,OhgushiM,NakamuraT,HirataS.Gustatorydiscriminationbehaviorandneuronalactivityinthegustatorycortexof
primates.FFI[InJapanesewithEnglishsummary]Journal2007;212:762–774
49.HayamaT,OgawaH.Callosalconnectionsofthecorticaltasteareainrats.BrainRes2001;918(1–2):171–175
50. Ito S, Ogawa H. Neural activities in the fronto-opercular cortex of macaque monkeys during tasting and mastication. Jpn J Physiol
1994;44(2):141–156
51. Hirata S, Nakamura T, Ifuku H, Ogawa H. Gustatory coding in the precentral extension of area 3 in Japanese macaque monkeys;
comparisonwithareaG.ExpBrainRes2005;165(4):435–446
52.Ogawa H,Hasegawa K,OtawaS,IkedaI. GABAergicinhibitionandmodificationsoftasteresponsesinthecorticaltasteareainrats.
NeurosciRes1998;32(1):85–95
53.IfukuH,HirataS, NakamuraT,OgawaH.Neuronal activitiesin themonkeyprimaryandhigher-ordergustatory corticesduring ataste
discriminationdelayedGO/NOGOtaskandafterreversal.NeurosciRes2003;47(2):161–175
54.SmallDM.Centralgustatoryprocessinginhumans.AdvOtorhinolaryngol2006;63:191–220
55.OnoT,TamuraR,NishinoH,NakamuraK.Neuralmechanismsofrecognitionandmemoryinthelimbicsystem.In:OnoR,SquireLR,
RaicheME,etal,eds.BrainMechanismsofPerceptionandMemory.NewYork,Oxford:OxfordUniversityPress;1993:330–369
56. Bermudez-Rattoni F, Yamamoto T. Neuroanatomy of CTA: lesions studies. In: Bures J, BermucezRattoni F, Yamamoto T, eds.
ConditionedTasteAversion.MemoryofaSpecialKind.Oxford:OxfordUniversityPress;1997:28–45
57.BörnsteinWS.Corticalrepresentationoftasteinmanandmonkey:II.Thelocalizationofthecorticaltasteareainmanandamethodof
measuringimpairmentoftasteinman.YaleJBiolMed1940;13(1):133–156
Данная книга находится в списке для перевода на русский язык сайта https://meduniver.com/
58.PenfieldW,JasperH.III–VIIIGustatorysensation.In:PenfieldW,JasperH,eds.EpilepsyandtheFunctionalAnatomyoftheHuman
Brain.Boston:Little,BrownandCompany;1954:147–149
59. Kobayakawa T, Ogawa H, Kaneda H, AyabeKanamura S, Endo H, Saito S. Spatio-temporal analysis of cortical activity evoked by
gustatorystimulationinhumans.ChemSenses1999;24(2):201–209
60. Cerf-Ducastel B, Van de Moortele PF, MacLeod P, Le Bihan D, Faurion A. Interaction of gustatory and lingual somatosensory
perceptionsatthecorticallevelinthehuman:afunctionalmagneticresonanceimagingstudy.ChemSenses2001;26(4):371–383
61.O'DohertyJ,RollsET,FrancisS,BowtellR,McGloneF.Representationofpleasantandaversivetasteinthehumanbrain.JNeurophysiol
2001;85(3):1315–1321
62. SmallDM,Zald DH, Jones-Gotman M,et al.Humancorticalgustatory areas:a reviewof functional neuroimagingdata. Neuroreport
1999;10(1):7–14
63. Kobayakawa T, Saito S, Gotow N, Ogawa H. Representation of salty taste stimulus concentrations in the primarygustatory area in
humans.ChemosensPercept2008;1:227–234
64. Barnikol UB, Amunts K, Dammers J, et al. Pattern reversal visual evoked responses of V1/V2 and V5/MT as revealed by MEG
combinedwithprobabilisticcytoarchitectonicmaps.Neuroimage2006;31(1):86–108
65. Ogawa H, Wakita M,Hasegawa K,et al. FunctionalMRI detection ofactivationin the primary gustatorycortices in humans. Chem
Senses2005;30(7):583–592
66.ShikamaY,KatoT,NagaokaU,etal.Localizationofthegustatorypathwayinthehumanmidbrain.NeurosciLett1996;218(3):198–200
67.LeeBC,HwangSH,RisonR,ChangGY.Centralpathwayoftaste:clinicalandMRIstudy.EurNeurol1998;39(4):200–203
68.OnodaK,IkedaM.Elucidationoftastedisorderscausedbycentrallesions.JMAJ2003;46:296–301
69. Onoda K, Kobayakawa T, Ikeda M, Saito S, Kida A. Laterality of human primary gustatory cortexstudiedby MEG. Chem Senses
2005;30(8):657–666
70. O'Doherty JP, Deichmann R, Critchley HD, Dolan RJ. Neural responses during anticipation of a primary taste reward. Neuron
2002;33(5):815–826
71.FelstedJA,RenX, Chouinard-DecorteF,Small DM.Geneticallydetermineddifferences in brainresponse toa primaryfoodreward.J
Neurosci2010;30(7):2428–2432
72.KringelbachML,O'DohertyJ,RollsET,AndrewsC.Activation ofthehumanorbitofrontalcortextoa liquid foodstimulus is correlated
withitssubjectivepleasantness.CerebCortex2003;13(10):1064–1071
73.O'DohertyJ,RollsET,FrancisS,etal.Sensory-specificsatiety-relatedolfactoryactivationofthehumanorbitofrontalcortex.Neuroreport
2000;11(4):893–897
74.SmallDM,PrescottJ.Odor/tasteintegrationandtheperceptionofflavor.ExpBrainRes2005;166(3–4):345–357
75.deAraujoIE,RollsET,KringelbachML,McGloneF,PhillipsN.Taste-olfactoryconvergence,andtherepresentationofthepleasantness
offlavour,inthehumanbrain.EurJNeurosci2003;18(7):2059–2068
76. Wilson JL, Jenkinson M, de Araujo I, Kringelbach ML, Rolls ET, Jezzard P. Fast, fully automated global and local magnetic field
optimizationforfMRIofthehumanbrain.Neuroimage2002;17(2):967–976
77.Haase L,Cerf-DucastelB,MurphyC.Corticalactivationin responsetopuretastestimuliduringthephysiologicalstatesofhunger and
satiety.Neuroimage2009;44(3):1008–1021
78.O'DohertyJ,RollsET,FrancisS,BowtellR,McGloneF.Representationofpleasantandaversivetasteinthehumanbrain.JNeurophysiol
2001;85(3):1315–1321
79.KobayakawaT,SaitoS,GotowN.Temporalcharacteristicsofneuralactivityassociatedwithperceptionofgustatorystimulusintensityin
humans.ChemosensPercept2012;5(1):80–86
14TasteTesting
TinoJust,MasafumiSakagami
GeneralRemarksonGustatoryTesting
Inthe general population,isolatedtastedisturbancesarerare.Usingtwodifferentpsychophysical taste
tests,hypogeusiawasfoundin~5%ofagroupof761healthysubjects.
1
Completeageusiaisveryrare.
Tastetestinginclinicalpracticeismainlyrestrictedtodepartmentsofotorhinolaryngologyandneurology,
or totasteandsmellcenters involved inthetreatment ofdiseases thatmaycausetaste disorders.Ear,
nose, and throat (ENT)-related causes of taste disturbance include middle ear surgery, tonsillectomy,
oropharyngeal surgery (including oncological treatment), and procedures associated with lingual
compression.
2
Taste in humans begins on the tongue, where taste cells of different gustatory papillae (fungiform,
foliate, and circumvallate papillae with taste buds) detect contact-chemical cues. The three different
morphological types of taste-detecting papillae are topographicallyarranged on thetongue. Fungiform
papillae are locatedonthe anterior two-thirds of thetongue, while foliate papillae and circumvallate
papillaearefoundonthelateraledgesandontheposteriorthirdofthetongue,respectively.Sensitivityto
alltastes(sweet,sour,salty,bitter,andumami)isfoundinallareasofthehumantongue,
3
andthereisno
evidencethatthereisatonguemap.
4
However,somestudieshaverevealedthatsometongueregionsare
more sensitive to natural stimuli than others.
5,6
Similar findings were reported in electrogustometric
studies.
7,8
In electrogustometry(electric stimulation ofsmall regionsofthe tongue) inhealthy humans,
electricthresholdsarehigheronthetongueedgethanonthetonguetip.
8
Thisshouldbekeptinmindwhen
comparinggustatoryresultsinhealthyhumanswiththoseinpatientswithtastedisorders.
This chapter describes common clinical taste tests, including questionnaires mainly in Europe and
Japan.
Isolatedtastedisturbancesarerare.
PatientHistory
In more than two-thirds of patients, a detailed patient history provides diagnostic evidence of
disturbancesoftheolfactoryandgustatorysystem.
9
Inmostcases,patientssufferingfromsmellandtaste
loss have isolated smell disorders or a combined olfactory and gustatory impairment rather than an
isolated taste disturbance.
10
Loss of smell presenting as taste loss, with normal findings on gustatory
testing, is described as a “flavor disturbance.”
10
Taste and flavor are generally used as synonyms.
Retronasalolfactionhasastronginfluenceonflavorperceptionandsupportstheneedforastandardized
psychophysical tasteandsmell test, rather than relying on the patients’ symptomsalone. Additionally,
patientswithanosmiahavepoorersensitivitytoalltastequalitiesthannormosmics.
11
Another aspect that is important to consider is innervation of the gustatorysystem. On bothsides,
differentnerves(thechordatympani for theanterior two-thirdsofthe tongueandtheglossopharyngeal
nervefortheposteriorpartofthetongue)provide a gustatorysupplyforthetongue;the petrosalnerve
suppliesthesoftpalate.
12
Somatosensorysupply isprovidedbythe trigeminalnerve.Patients reporting
numbness ortactiledysgeusia
13
ofthe tongueareoften unaware whetherthetrigeminalorthe gustatory
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systemisaffected.
Thefollowingaspectsneedtobeclarifiedinthepatienthistory:
•Surgeryintheheadandneckregion
14
:middleear,
15,16
includingstapes,surgery
17
;dentalprocedures;
tonsillectomy
18
; oropharyngeal surgery; oncological therapy; procedures with lingual compression,
suchassurgeryingeneralanesthesia;microlaryngoscopy
18
;trachealintubation;andsurgeryofthenasal
septumorparanasalcavities
•Trauma
•Medication:numerousdrugs
19
andtoxicagents
20
areknowntocausetastedisturbances
•Infections:influenza-likeinfectionsoftheupperrespiratoryairwaysmaycauselossofsmellandtendto
leadtotastedisturbances,butmayalsocauseflavordisturbances;infectionswithintheoralcavity,and
alsoofthemiddleear,maydamagethegustatorysystem
21
•Burningmouthsyndrome(primaryandsecondary):oralsymptomssuchasburning,tingling,pain,and
drynessmayaffectthegustatoryandtrigeminalsystemoftheoralcavity
22
• Systemic diseases: renal insufficiency, diabetes, diseases of the lower digestive tract, metabolic
disorders,Sjögrensyndrome
23
•Neurologicalorpsychiatricdiseases
Questionnaire
Tastedisordersarelesscommonthanolfactoryimpairmentsandmostactuallyreflectolfactorydisorders.
Tastedisorders are classified as qualitative or quantitative.
24
The latter includesageusia (inability to
taste) and hypogeusia (decreased ability to taste). Quantitative taste disorders are less frequent than
qualitative taste disorders and can be total (all tastes involved), partial (affecting several tastes), or
specific(onlyoneoraselectfewtastes).Qualitativedisorders,ordysgeusia,describeadistortedability
totaste,andincludeparageusia (unpleasant taste sensation, usuallymetallic, ontastestimulation) and
phantogeusia(oftenpermanenttasteinthemouth,e.g.,metallicorsalty,forwhichnoexternalstimuluscan
befound).
Theaccuracyofself-reportingindetectingtastedisordersispoor.
25
Therelativelylowprevalenceof
tastedisordersinthegeneralpopulation,andthetendencytoconfuseolfactorylosswithtasteimpairment,
contributestothislowaccuracy.
25
However,questionnaireshavebeenshowntobeaccurateindetecting
patientswithnotastedisorders:patientswhoreportednoproblemswiththeabilitytotastesweet,sour,
bitter,andsaltydemonstratednormaltastesensitivity.
In contrast to qualitative taste disorders, quantitative taste disorders can be measured by
psychophysicaltastetests.
PsychophysicalTasteTesting
Many psychophysical taste tests have been introduced to assess peripheral gustatory sensitivity. In
general,two testtools canbe distinguished.Thefirsttool usesnaturalstimulitomeasuretheabilityto
tastesweet,sour,salty,bitter,andumami.Thistoolmaybeusedasawhole-mouthmethodorasregional
tastetesttodetectsidedifferences.
Thesecondtooluseselectriccurrentsappliedtothetonguesurfacetoelicittasteperceptions,andis
namedelectrogustometry(EGM).EGMisanexcellentmethodformeasuringsidedifferencesinpatients
with taste disorders, provided that electric thresholds can be measured. It is assumed that
electrogustometry also costimulates the trigeminal system. Recent studies revealed that gustatory and
trigeminalfibersacttogetherperipherally.
26,27
Inclinicalpractice,particularlyinpatientswithsymptoms
such as numbness and burning of the tongue, it can be helpful to assess both the gustatory and the
trigeminalsystem.Therefore,asomatosensorytestwillalsobepresented.
In this section, we describe widely accepted taste tests and categorize them as tests using natural
chemicals (sweet, sour,salty, bitter, and umami), or those using non-natural stimuli (electric current).
Chemicaltastetestsarefurtherdividedintowhole-mouthtestsorregionaltests.
TasteTestswithNaturalChemicals
Whole-mouthTest
Three-dropMethod
ThistastetestusingliquidtastesolutionswasfirstintroducedbyHenkinetal
28
Amodifiedtestprocedure
andnormativedatafromtheclinicaltastetestwerepresentedin2007byGudziolandHummel.
29
Witha
10-μLpipette,aseriesofthreedropsofaliquidsolution(onedropoftastantandtwodropsofsolvent)is
placedinapseudorandomizedorderonthemidlineofthepatient’sextendedtongue.Afterswishingthe
drop in the closed mouth, the subject is asked to identify its taste quality. Four verbal gustatory
descriptors are presented (sweet, sour,salty, andbitter). A multiple forced-choice procedure is used.
Eight triplets are presented to the patient in ascending order, starting with the lowest concentration.
Between each triplet presentation, rinsing the mouth with tap water is allowed. Steps of increased
concentrationare presenteduntil the subjectrecognizes the taste solutioncorrectlyintwo consecutive
trials. Thus, scores for eachtastequality range between1 and 9. Toobtainthe overall gustatory test
result, the scores of all taste qualities are added to provide a total score. Age- and gender-related
normativedataareavailableforeachtastequalityandforthetotalscore(wholemouth).
29
TastingTabletsandWafers
Analternativeprocedureistousetabletsoffourtastants
30
(sweet,sour,salty,andbitter)insteadofliquid
solutions.Fourtastelesstabletsandtabletswithsixconcentrationsoffourtastants(sucrose,citricacid,
sodiumchloride,andcaffeine)arepresented.Theyareadministeredinascendingandpseudorandomized
order,starting with the lowestconcentration. The tastetestprovides a goodtest–retestreliability (r =
0.69,p <0.001).Similarresultswereachievedwith wafers.
31
Theflavored waferscanbe usedfora
regionalorwhole-mouthtastetest.
31
Themainadvantageoftastetestswithtabletsorwafersoverliquid
solutions is thelong shelf-life ofthe test kits. Themaindisadvantage is thelack of age- and gender-
relatednormativedata.
RegionalTests
TasteStrips
Thetastestriptestisawell-establishedquantitativetestusingimpregnatedtastestrips.Thistestwasfirst
introducedin2003.
32
Filterpaperstrips(tastestrips)withfourconcentrationsoffourtastants(sucrose,
citricacid,sodiumchloride,andquininehydrochloride)areused(Table14.1).Thestripsareplacedon
theleft or rightside oftheanteriorthirdofthe extendedtongue. Beforetastetestingandbetweeneach
application, the mouth is rinsed withwater.Tastestrips are presentedina randomizedand ascending
order,startingwiththelowestconcentrationofeachtastantandalternatingthesideofpresentation.This
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procedureresultsin32trials(16trialsofeachtongueside).Leavingthetongueextended,thepatienthas
toidentify the taste quality using gustatorydescriptors (sweet,sour, salty, bitter) inamultiple forced-
choiceprocedure.Besidesside-relatedscores,overallgustatorysensitivityiscalculatedbyaddingupthe
scoresofbothsidestocreateatotalscore.Withthetastestripmethod,atest–retestreliabilityofr=0.68
wasachieved(three-dropmethodr=0.69).
32
Age-andgender-relatednormativedataforthetastestrip
testwerepresentedin2009.
33
Thistestisusefulinroutineclinicalpractice.Theaimoffurtherstudiesis
toaddmonosodiumglutamate(umamitaste)andtoextendthevalidatedtest.
FilterPaperDiscMethod
Thefilterpaperdisc(FPD)test(Fig.14.1)isaqualitativeclinicaltastingtestdevelopedbyTomitaet
al
34
Itmeasuresfour(sweet,sour,salty,andbitter)tastequalitiesatfivedifferentconcentrations(Table
14.1).TheFPDtestusesaroundfilterpaperdisc,5mmindiameter,impregnatedwithadropoftastant
solution.Sucroseisusedforthesweettaste,sodiumchlorideforthesaltytaste,tartaricacidforthesour
taste,andquininehydrochlorideforthebittertaste.Theimpregnatedfilterpaperdiscsareplacedatthe
same pointsonthe tongue as forEGM. Thetastesolutionsare presented inascending order from the
lowestconcentration.Thetastequalities andarea, however,are presentedina randomizedorder. The
bittertasteshouldbepresentedlast.Whendifferenttastesolutionsarepresented,themouthneedstobe
rinsedwithwater.Patientshavetoidentifythetastefromalistoffourdescriptors(sweet,salty,sour,and
bitter) while their tongue is extended.Whenpatients cannot identify the tasteclearly, theycanchoose
“Undefinedtaste”or“Notaste,”unlikeinthetastestriporthree-dropmethods.ThescoresoftheFPDtest
rangefrom1to5foreachtastequality,andtheregionsarelateralized.Whenthetastecanbeperceivedin
the third concentration, taste function is assessed as “within normal limits.” When the taste is not
identifiedinthefifthconcentration,thescoreiscalculatedas“6.”Theaveragescoreforpeopleover60
years old is ~1 point higher thanthat foryoungpeople.TheFPDscore forthe area innervated bythe
greaterpetrosalnerveisparticularlyinfluencedbyage.Whenhighscoresareobservedinthisarea,this
findingmightbeoflittlesignificance.Theage-relatedchangesstartattheageof30years.
Fig.14.1Filterpaperdisctest.
Tomita et al
34
demonstrated a significant correlation between EGM and FPD tests in an area
innervatedbythechordatympaninerveinpatientswithfacialpalsy.Ellegårdetal
35
reportedthatthere
wasasignificantcorrelationbetweenEGMthresholdandthewhole-mouthperceptionofalltastes,andit
wasnostrongerforsourtasteperceptionthanforothertastequalities.
LiquidSolutions
Regional taste tests are also available with liquid tastants.
36
For lateralized assessment of gustatory
sensitivity,~20 μL ofliquidtastants (sucrose, citric acid, sodiumchloride,andquininehydrochloride)
are administered using aglass probe onbothsides oftheanterior third ofthe extendedtongue (Table
14.1). The administrationofthe testis similar to taste strips, apart from the descriptors available for
answering (“no taste” was added) and the concentrations of the gustatory stimuli. The test–retest
reliabilityofthistestisr=0.77.Age-andgender-relatednormativedataareavailable.
Electrogustometry
The first electrogustometer for clinical use, together with preliminary results from 140 patients, was
reported in 1959.
37–39
Krarup replaced the taste solution for taste testing with an inadequate taste
stimulus,anelectriccurrent.
The existence of electrical taste is common knowledge. When a stimulus produced from a direct-
current stainless steel node is applied to the tongue, a taste sensation similar to that of licking metal
(metallictaste)isperceived.Theelectrogustometer(RIONTR-06model,RionCo.,Ltd,Tokyo,Japan)
(Fig.14.2)iswidelyusedforthequantitativeassessmentoflateralizedgustatoryfunctioninJapan.Ithas
alsobeenusedforavarietyofclinicalpurposes,includingevaluationofperipheralnervousfunctionin
patients with facial palsy, peripheral nervousdamage in diabetes, damage tothe chordatympaniafter
middle ear surgery,andotherconditions.The electrogustometercomprises ananode, a cathode, and a
switchtoinitiatethestimulation.Theneutralelectrodemustbeappliedtotheneckofthepatientstoavoid
passinganelectriccurrentthroughtheirheart.Patientswithapacemakeroracochlearimplantshouldnot,
intheory,beexaminedusingthismethod.
Themagnitudeoftheelectricstimulationcanbevariedcontinuouslyonalogarithmicscaleemploying
themethodofTomitaetal.
34
Accordingtothescale,8µA,whichisthearithmeticmeanvaluefornormal
subjects,isdefinedas0dB.Thelowestcurrentlevelis4µA(−6dB)andthehighestis400µA(34dB).
Thescorescale-outisdefinedas36dB.Beforetheassessment,patientsaretoldthatelectrictasteisnota
tactile sensation but a metallic taste, and are presented with a 10 to 20 dB current, which can be
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