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The Senseof Smell the Olfactory Sense Thisis the third in the verysuccessful seriesof articlesthat DavidBrown,from California Deafblind is writingon the senses Services, he senseof smellis crucially important for the existence of
David Brown
merelycollectsthe relevant information, so that every time we inhale,air swirlsup almostall creatures,for through the nostrilsto the finding the next meal,for millionsof smellreceptor avoidingmany dangers,or cellsthat are all contained for choosinga partner.We deepwithin the nasal humans,ableto distinguish cavityin an areaknown as thousandsof differentodour the olfactoryepithelium, molecules,utilizeour sense which is about the sizeof a postagestamp.Thesecells of smellfor a multitudeof activitiesfrom maintaining are sensitiveto chemicals personalhygiene,to enjoying producedwhen odours the aroma of freshlybaked dissolvein the mucousinside bread,to decidingwhom not the nose,and they are much to sit next to on the bus. more sensitivethan the taste We think that we smell receptors,being capableof with our noses,but this is collectingand transmitting no more true than if we informationthat helps saythat we hearwith our us to discriminatemany externalearsor that we see thousandsof differentsmells. with our corneas,The part Researchers haveclaimed of the nosethat we can see that smellis 10,000times more sensitivethan taste, and the systemis so complex that, unlikethe five taste groups, no researchhasyet beenable to discoverbasic categoriesof smell.In fact, we tend to pay little attention to the senseof smell,except for obviousattentionpaid to bad smells,and the publicity of the perfume and cosmetics industry so that we don't even havea proper range of words to describeit. Just considerhow manywords we haveto descibedifferent shadesof blue for example (pale,light, dark,deep, eggshell,teal, navy,royal, Prussian, sky,aquamarine, and so on), and how few
4 . Dbl Review . Jur-vDrcrr.,rern2007
words we haveto describe the variousdifferent smells of rosesor dogs. So it is very hard to usewords to explain exactlyhow somethingsmells to somebodywho hasn't smelledit. Thesenseof smellis uniquein that, unlikeall other sensorysystems,it sendsinformation directlyto highercentersof the brain and completelybypasses the thalamus,which is the areaof the brainwhere all other incomingsensory information is sorted into the two basiccategoriesof what needsour attention and what does not need our attention.Because it doesn'thaveto passthrough this preliminarysortingand analyzingprocess,smellis the sensethat puts our brains into directcontactwith the environmentin a way that none of the other sensescan. So the senseof smellhas quick,direct,and powerful connectionsto the limbic system,the part of the brain concernedwith primitive instinctsand drives,the part that processes emotionsand memories.In'Understanding Deafblindness' Geegee Larringtonrefersto smell informationtraveling'...on short, large,fast fibers to deep within the brain'.This is why particularsmells can evokesuchvery strong emotionsand memories,
...smell isthesense thatputsourbrains intodirectcontactwith the environment in a waythat noneof the othersenses can all basedupon associations madethrough previous experiences, and do it so quicklyand so vividly. The senseof smelldepends on the functioningof not only the first cranial nerve(the olfactory nerve) but also partsof the fifth cranialnerve(the trigeminal nerve).Qualitativesmell (for example sensations the distinctive and unique identifyingsmellof a lily, or an orange,or freshlycut grass)are transmittedby the first cranialnerve,whereas other aspectsof smells(for examplethe heat,coldness, sharpness, spiciness, and irritatingqualities of a particular smell)are transmittedby partsof the fifth cranialnerve.lt is helpful to know that more than the 'smellnerve'is involvedin our perceptionof smell.In the populationof children with CHARGE Syndrome,for example,which is one of the leadingcausesof congenital deafblindness in children,we know that about 42o/ohave damageto the first cranial nerveand 43% havedamage to the fifth cranialnerve,so that thereis a high incidence of missingor reducedsense of smell. Likethe taste receptors, the smellreceptorsdevelop veryearlyin a foetus, stimulatedby chemicals in the amnioticfluid that
they inhaleand exhale whilestillin the womb, so that babiesare born with an alreadywell developed senseof smell.Babiesalso appearto be born with an innateabilityto detectbad, aversivesmells,sinceit is reportedthat one-dayold babiesgivefacialexpressions that indicaterejectionwhen they are exposedto fish or rotten egg smells.But the fact that we experience so much smellsensationbefore birth complicatesthis whole area,just as it doeswith earlytaste preferencesand aversions. Sincebabiesare exposedto a selectionof 'smells'overa long periodin the womb this seemslikely to exerta powerfulinfluence on their smellpreferences immediatelyafter birth. Thereis clearlyexperiencedependentlearningin the smellsense,but whetherthe responseto certainsmells(in particularwhat we consider to be bad smells)is innateor not hasstill not beensettled. As with taste,so our sense of smelldeclinesas we get older,so thereis a double impacton the lossof flavour from food and drink,as well as on more generalized aspectsof environmental awareness. By 80 years of age 80% of peopleare reportedto havesomemajor smelldysfunction,and 507o arefunctionally anosmic
(the word usedto describe someonewho haslost some or all of theirsenseof smell). Not only is there a lossof the senseof smell,but alsoa loss of the abilityto discriminate betweensmells.Disturbance of the senseof smellhas many possiblecauses.In most instances,lossof smellis causedby nasal and sinusdisease, upper respiratorytract infection,or headtrauma.Patientswith neurodegenerative d iseases, suchas Alzheimer'sdisease, experience significantloss of smellperception.In fact, one of the common very earlystagesof Alzheimer's is a lossof smellsensitivity. Medications,especially those that increasedehydration and limit mucousproduction, are alsoan importantand frequentlyoverlookedcause of smellimpairment. Smelland tasteare the two chemicalsenses,so calledbecausethey detect chemicals, and smells and tastesare,of course, chemicals. With both of thesesenseswe sampleour environmentfor information. Unliketaste,of course, smellcan signaloverlong distancesand so form part of our earlywarningalarm system.With our senseof smellwe are continuously testingthe qualityof the air we breathe,which will alert us to potentialdangers J u t v- D r c e v e e2n0 0 7
. D b l R e v i e w. 5
Therearealsosuggestions that smellcaninfluencearousal levels,mood,emotions,the immunesystem,and the endocrine systemthat produces and controlshormones. So a greatdealcanbe communicated andcontrolled by smell without us evenknowingit. likesmokeor leakinggas, as well as informingus of other relevantinformation, suchas the presenceof food, or cooking,or of anotherperson.Thesense of smellalsoservesa recognition function,in that we all haveour own uniquesmelland we can recogniseand be recognised by our smell.Somechildren with deafblindness very clearlysniff other people becausethis is a help to them in identifyingfamiliar individuals. Research has shownthat childrencan distinguishbetweenthe smell of theirsiblingsand other childrenof the sameage,and alsothat babiesrecognise their own mothers'smelland mothersrecognisetheir own babies'smell.Emotioncan be communicated by smell, as when dogsaresaidto pick up and respondto the smell of fear in humans.Research in the 1990sshowedthat peoplecan discriminate betweenthe smellof people watching"happy"and "sad" films,which suggests that the emotionsof others,for examplefeal contentment, and excitement,may thereforebe transmitted and recognizedby smell. How we smell,why we smell,and the impactof smellon our everydaylife are poorlyunderstood,and we certainlyunderestimate 6 . Dbl Review.
Jurv- Drcevsen 2007
the importanceof smellto our functioningand to our generalwell-being.Research suggestsa closecorrelation betweenmissingsenseof smelland depression, for example.Physiologically, the two chemicalsenses of tasteand smellaid in normaldigestionby triggeringgastrointestinal secretions. Thereare also suggestions that smell can influencearousal levels,mood, emotions, the immunesystem,and the endocrinesystemthat producesand controls hormones.So a great deal can be communicated and controlledby smellwithout us evenknowing it. The senseof smellis intimatelylinkedwith memory smellevokes memories.Damageto the temporalcorticalregionof the brain,the site of memory, doesn'taffectthe abilityto detectsmell,but, rathel preventsthe identificationof the smell,becausewe must first remembera smellbefore we can identifyit. Smell memoryfallsoff lessrapidly than other sensorymemory in fact smellmemory normallylastsa long time. Likethe stimuliwe receive through other senses,a smell can becomeassociated with a particularexperience and the samesmellcan recall whole complexmemories,
completewith all associated emotions;smellis betterat this memorycue effectthan other senses,and it doesit veryquicklyand powerfully. FrenchnovelistMarcelProust claimsthat: 'When
nothing e/sesubsrsts from the past,after the people are dead, after the things are brokenand scattered...the smelland taste of things remain poised a long time, like souls... bearing resiliently,on tiny and almost impalpable drops of their essence,the immense edifice of memory.' Thisis entirelyunconscious, althoughcountless studies haveshown that recallof specificfactualinformation can be enhancedif the originallearningwas done in the presenceof a smell and that samesmellis presentedat the time of recall.But researchhasalso shown that smellmemory is contextdependentand can be modifiedin the light of new experience, which impliesthat our smellsense is continuously dynamic, updatingas we liveand experiencenew things.
Sm elland children with deafblindn es s Most of us haveheard storiesabout the surprising
(Left) Nick feels and smellsthe ice cream ball (Right)Nick enjoys the heavy weight and string smell of the ice cream ball
effectsof smellsensations on somechildrenwith deafblindness. A young childwith significant visual and hearingimpairments who alwaysbecamevery upsetwhen beingtaken into the hospitalbuildingeven though he could not possibly haveseenand recognized the buildingnor understood from spokenconversations that he was beingtakento a hospital.Anotherchild would becomeexcitedand beginto salivateas lunchwas beingcookedin the room next door,eventhough he had not seenor heardthe food being prepared.An olderchildwould routinely searchfor the hand of every new personwho enteredher classroomand lift it to her noseverydeliberatelyand sniff it; then shewould either drop the handand walk away,or shewould smileand embracethe other person. Whena girlwith profound disabilities was allowed time to smellthe dishof lavender-scented oil that was alwaysusedin her weekly massagesessionher eyes would open wider,shewould becomegraduallymore animated.and shewould breakher customarysilence with quietvocalizations. All of theseare examples of waysin which the sense of smellcan offer vital and meaningfulinformationto
childrenwith deafblindness and enablethem to connect with theirenvironment and to recognizeand anticipate what is comingcorrectly. Somechildrenwith deafblind nessare anosmic, they haveno senseof smell (we think that this is the casewith manychildren with CHARGE Syndrome, for example,becauseof the cranialnervedamagealready mentionedand becauseof blockednasalpassages),
if we think of the sensory deprivationinherentin the term 'deafblindness' it seems obviousthat the relative importanceof other intact sensorychannelslike smell and tastemight be enhanced as long as the inputscoming through thosesensory channels are meaningfulfor the child. Sometimespeople involvedwith a child with deafblindness think of using smellsin a deliberateway to
Howwe smell, whywe smell,andthe impactof smell on oureveryday lifearepoorlyunderstood, andwe underestimate the importance certainly of smellto our functioning andto our generalwell-being. and othersdon't appearto show any awarenessof the senseeventhough it may be intactand working.In other caseschildrengive veryclearevidencethat smellis an importantsensory inputfor them,as in the examplesmentionedabove, and manychildrenshow levelsof environmentaland socialawareness that are surprising and perplexing to us (likethe boy upset by hospitalvisits),until we realizethat their senseof smellmust havegiventhem the essentialinformationthey neededfor this awareness Indeed, and recognition.
help the child know what is goingon, and in thesecases the followingguidelines might be helpful. 1. Firstit is helpfulto observe for, and discuss,the waysthe child already respondsto smells.How do they show that they haveperceiveda smell, and which smell?Canthey locateits sourcein the room? Do they seekout smells?Do they recognize smells,and how do they show that they do? These are all importantquestions to be askingand discussing beforeany work is done -
.
o
on enhancingsmellsor addingnew smellsto the child'senvironment.
4. Many smellsreleasedinto www. handle.org/miscinfo/ the atmosphereremain environ.html). perceptiblefor a very periodof considerable 6. Hypersensitivity might 2. Helpingthe childto time, and they can't be be reducedif essential 'put away' likewe would becomemore awareof oils are usedto provide smellsthat are already switchoff a light or a certainsmellsrather presentin their existing radio, or removea toy than an impuresource environments and in their from a childand put it likean aerosolsprayor regularroutinesmight be away in a drawer.lf too someother type of air a usefulthing to do, and many differentand strong freshener.Essential oils thereare usuallymany smellsare deliberately are powerfulchemical more of theseroutine introducedin one place substances,however, smellsaroundthan we they will blendtogether; so shouldonly everbe realize.Thisidea might which could cause usedafter consultation involvestrengthening confusionand distraction, with an aromatherapist. theseexistingsmellsif and might evenbe a Essential oils can be used potentialhealthhazard this is possible, or it might in massagesessions, (dependingupon the type mean investigatingwaysto and this is one activity draw the child'sattention of chemicalsbeing used). where it seemslike a very to the smellsin a way that good ideato introduce Everybodyin the room will helpsthem connectthe be exposedto thesesmells, a consistentsmellin the just smellwiththe upcoming not the childfor massagelotion to help to 'label'the activityfor the activity.Theseactivities whom they are intended. might alsohelpthe child It is reportedthat the child with deaf-blindness. 'tires' to learnto seekout smells senseof smell and lf usedin a massage more consciously and the nosebeginsto loseits lotiontheseoilswill be deliberately. Timespent sensitivityafter exposure absorbedboth through exploringand thinking to three or four different the noseand through the aboutthis,and discussing smellsin succession. skinso it is particularly your ideaswith others, importantto consultan shouldbe helpful. 5. All of us have aromatherapist and to hypersensitivities to certain follow all safetyguidelines. 3. Any ideasabout smellsand to certain Formassagepurposes introducingnew smells intensitiesof smell,and, any essential oil should artificiallyshouldbe whilesomechildren alwaysbe greatlydiluted treatedwith caution. with deafblindness in a blandcarrieroil, and lf the new smellis not may demonstratethese the dilution needsto be greaterfor young children alreadyan integralpart hypersensitivities with of the activity or of the obviousaversiveresponses, than for adults.Many environmentit might, recommendthat othersmight not be able specialists in fact, be a distraction to let us know that they no essentialoil be used and createconfusion are suffering.Because in massagelotion for the of pathway youngestinfants,and for the child.Sincethe nerve very that unique from the insideof the nose smellis being introduced then only essentialoil of artificiallyit might also directlyinto the brain it is lavenderor chamomilebe particularlyimportantto usedwith older children be difficultfor everybody (both of theseoils are said involvedwith the child usecaution,discretion, to rememberalwaysto and closeobservation to havecalming,soothing properties). introduceit consistently when exposinga child to and appropriately, and to a rangeof enhancedsmell (Formore rememberexactlywhich experiences. With thanks to CDBS smellis to be usedwith informationon thesekinds see Email : [email protected] which activityor in which of hypersensitivities location.
David Brown
merelycollectsthe relevant information, so that every time we inhale,air swirlsup almostall creatures,for through the nostrilsto the finding the next meal,for millionsof smellreceptor avoidingmany dangers,or cellsthat are all contained for choosinga partner.We deepwithin the nasal humans,ableto distinguish cavityin an areaknown as thousandsof differentodour the olfactoryepithelium, molecules,utilizeour sense which is about the sizeof a postagestamp.Thesecells of smellfor a multitudeof activitiesfrom maintaining are sensitiveto chemicals personalhygiene,to enjoying producedwhen odours the aroma of freshlybaked dissolvein the mucousinside bread,to decidingwhom not the nose,and they are much to sit next to on the bus. more sensitivethan the taste We think that we smell receptors,being capableof with our noses,but this is collectingand transmitting no more true than if we informationthat helps saythat we hearwith our us to discriminatemany externalearsor that we see thousandsof differentsmells. with our corneas,The part Researchers haveclaimed of the nosethat we can see that smellis 10,000times more sensitivethan taste, and the systemis so complex that, unlikethe five taste groups, no researchhasyet beenable to discoverbasic categoriesof smell.In fact, we tend to pay little attention to the senseof smell,except for obviousattentionpaid to bad smells,and the publicity of the perfume and cosmetics industry so that we don't even havea proper range of words to describeit. Just considerhow manywords we haveto descibedifferent shadesof blue for example (pale,light, dark,deep, eggshell,teal, navy,royal, Prussian, sky,aquamarine, and so on), and how few
4 . Dbl Review . Jur-vDrcrr.,rern2007
words we haveto describe the variousdifferent smells of rosesor dogs. So it is very hard to usewords to explain exactlyhow somethingsmells to somebodywho hasn't smelledit. Thesenseof smellis uniquein that, unlikeall other sensorysystems,it sendsinformation directlyto highercentersof the brain and completelybypasses the thalamus,which is the areaof the brainwhere all other incomingsensory information is sorted into the two basiccategoriesof what needsour attention and what does not need our attention.Because it doesn'thaveto passthrough this preliminarysortingand analyzingprocess,smellis the sensethat puts our brains into directcontactwith the environmentin a way that none of the other sensescan. So the senseof smellhas quick,direct,and powerful connectionsto the limbic system,the part of the brain concernedwith primitive instinctsand drives,the part that processes emotionsand memories.In'Understanding Deafblindness' Geegee Larringtonrefersto smell informationtraveling'...on short, large,fast fibers to deep within the brain'.This is why particularsmells can evokesuchvery strong emotionsand memories,
...smell isthesense thatputsourbrains intodirectcontactwith the environment in a waythat noneof the othersenses can all basedupon associations madethrough previous experiences, and do it so quicklyand so vividly. The senseof smelldepends on the functioningof not only the first cranial nerve(the olfactory nerve) but also partsof the fifth cranialnerve(the trigeminal nerve).Qualitativesmell (for example sensations the distinctive and unique identifyingsmellof a lily, or an orange,or freshlycut grass)are transmittedby the first cranialnerve,whereas other aspectsof smells(for examplethe heat,coldness, sharpness, spiciness, and irritatingqualities of a particular smell)are transmittedby partsof the fifth cranialnerve.lt is helpful to know that more than the 'smellnerve'is involvedin our perceptionof smell.In the populationof children with CHARGE Syndrome,for example,which is one of the leadingcausesof congenital deafblindness in children,we know that about 42o/ohave damageto the first cranial nerveand 43% havedamage to the fifth cranialnerve,so that thereis a high incidence of missingor reducedsense of smell. Likethe taste receptors, the smellreceptorsdevelop veryearlyin a foetus, stimulatedby chemicals in the amnioticfluid that
they inhaleand exhale whilestillin the womb, so that babiesare born with an alreadywell developed senseof smell.Babiesalso appearto be born with an innateabilityto detectbad, aversivesmells,sinceit is reportedthat one-dayold babiesgivefacialexpressions that indicaterejectionwhen they are exposedto fish or rotten egg smells.But the fact that we experience so much smellsensationbefore birth complicatesthis whole area,just as it doeswith earlytaste preferencesand aversions. Sincebabiesare exposedto a selectionof 'smells'overa long periodin the womb this seemslikely to exerta powerfulinfluence on their smellpreferences immediatelyafter birth. Thereis clearlyexperiencedependentlearningin the smellsense,but whetherthe responseto certainsmells(in particularwhat we consider to be bad smells)is innateor not hasstill not beensettled. As with taste,so our sense of smelldeclinesas we get older,so thereis a double impacton the lossof flavour from food and drink,as well as on more generalized aspectsof environmental awareness. By 80 years of age 80% of peopleare reportedto havesomemajor smelldysfunction,and 507o arefunctionally anosmic
(the word usedto describe someonewho haslost some or all of theirsenseof smell). Not only is there a lossof the senseof smell,but alsoa loss of the abilityto discriminate betweensmells.Disturbance of the senseof smellhas many possiblecauses.In most instances,lossof smellis causedby nasal and sinusdisease, upper respiratorytract infection,or headtrauma.Patientswith neurodegenerative d iseases, suchas Alzheimer'sdisease, experience significantloss of smellperception.In fact, one of the common very earlystagesof Alzheimer's is a lossof smellsensitivity. Medications,especially those that increasedehydration and limit mucousproduction, are alsoan importantand frequentlyoverlookedcause of smellimpairment. Smelland tasteare the two chemicalsenses,so calledbecausethey detect chemicals, and smells and tastesare,of course, chemicals. With both of thesesenseswe sampleour environmentfor information. Unliketaste,of course, smellcan signaloverlong distancesand so form part of our earlywarningalarm system.With our senseof smellwe are continuously testingthe qualityof the air we breathe,which will alert us to potentialdangers J u t v- D r c e v e e2n0 0 7
. D b l R e v i e w. 5
Therearealsosuggestions that smellcaninfluencearousal levels,mood,emotions,the immunesystem,and the endocrine systemthat produces and controlshormones. So a greatdealcanbe communicated andcontrolled by smell without us evenknowingit. likesmokeor leakinggas, as well as informingus of other relevantinformation, suchas the presenceof food, or cooking,or of anotherperson.Thesense of smellalsoservesa recognition function,in that we all haveour own uniquesmelland we can recogniseand be recognised by our smell.Somechildren with deafblindness very clearlysniff other people becausethis is a help to them in identifyingfamiliar individuals. Research has shownthat childrencan distinguishbetweenthe smell of theirsiblingsand other childrenof the sameage,and alsothat babiesrecognise their own mothers'smelland mothersrecognisetheir own babies'smell.Emotioncan be communicated by smell, as when dogsaresaidto pick up and respondto the smell of fear in humans.Research in the 1990sshowedthat peoplecan discriminate betweenthe smellof people watching"happy"and "sad" films,which suggests that the emotionsof others,for examplefeal contentment, and excitement,may thereforebe transmitted and recognizedby smell. How we smell,why we smell,and the impactof smellon our everydaylife are poorlyunderstood,and we certainlyunderestimate 6 . Dbl Review.
Jurv- Drcevsen 2007
the importanceof smellto our functioningand to our generalwell-being.Research suggestsa closecorrelation betweenmissingsenseof smelland depression, for example.Physiologically, the two chemicalsenses of tasteand smellaid in normaldigestionby triggeringgastrointestinal secretions. Thereare also suggestions that smell can influencearousal levels,mood, emotions, the immunesystem,and the endocrinesystemthat producesand controls hormones.So a great deal can be communicated and controlledby smellwithout us evenknowing it. The senseof smellis intimatelylinkedwith memory smellevokes memories.Damageto the temporalcorticalregionof the brain,the site of memory, doesn'taffectthe abilityto detectsmell,but, rathel preventsthe identificationof the smell,becausewe must first remembera smellbefore we can identifyit. Smell memoryfallsoff lessrapidly than other sensorymemory in fact smellmemory normallylastsa long time. Likethe stimuliwe receive through other senses,a smell can becomeassociated with a particularexperience and the samesmellcan recall whole complexmemories,
completewith all associated emotions;smellis betterat this memorycue effectthan other senses,and it doesit veryquicklyand powerfully. FrenchnovelistMarcelProust claimsthat: 'When
nothing e/sesubsrsts from the past,after the people are dead, after the things are brokenand scattered...the smelland taste of things remain poised a long time, like souls... bearing resiliently,on tiny and almost impalpable drops of their essence,the immense edifice of memory.' Thisis entirelyunconscious, althoughcountless studies haveshown that recallof specificfactualinformation can be enhancedif the originallearningwas done in the presenceof a smell and that samesmellis presentedat the time of recall.But researchhasalso shown that smellmemory is contextdependentand can be modifiedin the light of new experience, which impliesthat our smellsense is continuously dynamic, updatingas we liveand experiencenew things.
Sm elland children with deafblindn es s Most of us haveheard storiesabout the surprising
(Left) Nick feels and smellsthe ice cream ball (Right)Nick enjoys the heavy weight and string smell of the ice cream ball
effectsof smellsensations on somechildrenwith deafblindness. A young childwith significant visual and hearingimpairments who alwaysbecamevery upsetwhen beingtaken into the hospitalbuildingeven though he could not possibly haveseenand recognized the buildingnor understood from spokenconversations that he was beingtakento a hospital.Anotherchild would becomeexcitedand beginto salivateas lunchwas beingcookedin the room next door,eventhough he had not seenor heardthe food being prepared.An olderchildwould routinely searchfor the hand of every new personwho enteredher classroomand lift it to her noseverydeliberatelyand sniff it; then shewould either drop the handand walk away,or shewould smileand embracethe other person. Whena girlwith profound disabilities was allowed time to smellthe dishof lavender-scented oil that was alwaysusedin her weekly massagesessionher eyes would open wider,shewould becomegraduallymore animated.and shewould breakher customarysilence with quietvocalizations. All of theseare examples of waysin which the sense of smellcan offer vital and meaningfulinformationto
childrenwith deafblindness and enablethem to connect with theirenvironment and to recognizeand anticipate what is comingcorrectly. Somechildrenwith deafblind nessare anosmic, they haveno senseof smell (we think that this is the casewith manychildren with CHARGE Syndrome, for example,becauseof the cranialnervedamagealready mentionedand becauseof blockednasalpassages),
if we think of the sensory deprivationinherentin the term 'deafblindness' it seems obviousthat the relative importanceof other intact sensorychannelslike smell and tastemight be enhanced as long as the inputscoming through thosesensory channels are meaningfulfor the child. Sometimespeople involvedwith a child with deafblindness think of using smellsin a deliberateway to
Howwe smell, whywe smell,andthe impactof smell on oureveryday lifearepoorlyunderstood, andwe underestimate the importance certainly of smellto our functioning andto our generalwell-being. and othersdon't appearto show any awarenessof the senseeventhough it may be intactand working.In other caseschildrengive veryclearevidencethat smellis an importantsensory inputfor them,as in the examplesmentionedabove, and manychildrenshow levelsof environmentaland socialawareness that are surprising and perplexing to us (likethe boy upset by hospitalvisits),until we realizethat their senseof smellmust havegiventhem the essentialinformationthey neededfor this awareness Indeed, and recognition.
help the child know what is goingon, and in thesecases the followingguidelines might be helpful. 1. Firstit is helpfulto observe for, and discuss,the waysthe child already respondsto smells.How do they show that they haveperceiveda smell, and which smell?Canthey locateits sourcein the room? Do they seekout smells?Do they recognize smells,and how do they show that they do? These are all importantquestions to be askingand discussing beforeany work is done -
.
o
on enhancingsmellsor addingnew smellsto the child'senvironment.
4. Many smellsreleasedinto www. handle.org/miscinfo/ the atmosphereremain environ.html). perceptiblefor a very periodof considerable 6. Hypersensitivity might 2. Helpingthe childto time, and they can't be be reducedif essential 'put away' likewe would becomemore awareof oils are usedto provide smellsthat are already switchoff a light or a certainsmellsrather presentin their existing radio, or removea toy than an impuresource environments and in their from a childand put it likean aerosolsprayor regularroutinesmight be away in a drawer.lf too someother type of air a usefulthing to do, and many differentand strong freshener.Essential oils thereare usuallymany smellsare deliberately are powerfulchemical more of theseroutine introducedin one place substances,however, smellsaroundthan we they will blendtogether; so shouldonly everbe realize.Thisidea might which could cause usedafter consultation involvestrengthening confusionand distraction, with an aromatherapist. theseexistingsmellsif and might evenbe a Essential oils can be used potentialhealthhazard this is possible, or it might in massagesessions, (dependingupon the type mean investigatingwaysto and this is one activity draw the child'sattention of chemicalsbeing used). where it seemslike a very to the smellsin a way that good ideato introduce Everybodyin the room will helpsthem connectthe be exposedto thesesmells, a consistentsmellin the just smellwiththe upcoming not the childfor massagelotion to help to 'label'the activityfor the activity.Theseactivities whom they are intended. might alsohelpthe child It is reportedthat the child with deaf-blindness. 'tires' to learnto seekout smells senseof smell and lf usedin a massage more consciously and the nosebeginsto loseits lotiontheseoilswill be deliberately. Timespent sensitivityafter exposure absorbedboth through exploringand thinking to three or four different the noseand through the aboutthis,and discussing smellsin succession. skinso it is particularly your ideaswith others, importantto consultan shouldbe helpful. 5. All of us have aromatherapist and to hypersensitivities to certain follow all safetyguidelines. 3. Any ideasabout smellsand to certain Formassagepurposes introducingnew smells intensitiesof smell,and, any essential oil should artificiallyshouldbe whilesomechildren alwaysbe greatlydiluted treatedwith caution. with deafblindness in a blandcarrieroil, and lf the new smellis not may demonstratethese the dilution needsto be greaterfor young children alreadyan integralpart hypersensitivities with of the activity or of the obviousaversiveresponses, than for adults.Many environmentit might, recommendthat othersmight not be able specialists in fact, be a distraction to let us know that they no essentialoil be used and createconfusion are suffering.Because in massagelotion for the of pathway youngestinfants,and for the child.Sincethe nerve very that unique from the insideof the nose smellis being introduced then only essentialoil of artificiallyit might also directlyinto the brain it is lavenderor chamomilebe particularlyimportantto usedwith older children be difficultfor everybody (both of theseoils are said involvedwith the child usecaution,discretion, to rememberalwaysto and closeobservation to havecalming,soothing properties). introduceit consistently when exposinga child to and appropriately, and to a rangeof enhancedsmell (Formore rememberexactlywhich experiences. With thanks to CDBS smellis to be usedwith informationon thesekinds see Email : [email protected] which activityor in which of hypersensitivities location.
