雅思閱讀模擬試題一例

1、Rightandleft-handednessinhumansWhydohumans,virtuallyaloneamongallanimalspecies,displayadistinctleftorrighthandedness?Notevenourclosestrelativesamongtheapespossesssuchdecidedlateralasymmetry,aspsychologistscallit.Yetabout90percentofeveryhumanpopulationthathaseverlivedappearstohavebeenright-handed.Pro

2、fessorBryanTurneratDeakinUniversityhasstudiedtheresearchliteratureonleft-handednessandfoundthathandednessgoeswithsidedness.Sonineoutoftenpeopleareright-handedandeightareright-footed.Henotedthatthisdistinctiveasymmetryinthehumanpopulationisitselfsystematic.Humansthinkincategories:blackandwhite,upandd

3、own,leftandright.Itsasystemofsignsthatenablesustocategorisephenomenathatareessentiallyambiguous.Researchhasshownthatthereisgeneticorinheritedelementtohandedness.Butwhileleft-handednesstendstoruninfamilies,neitherleftnorrighthanderswillautomaticallyproduceoff-springwiththesamehandedness;infactabout6p

4、ercentofchildrenwithtworight-handedparentswillbeleft-handed.However,amongtwoleft-handedparents,perhaps40percentofthechildrenwillalsobeleft-handed.Withonerightandoneleft-handedparent,15to20percentoftheoffspringwillbelefthanded.Evenamongidenticaltwinswhohaveexactlythesamegenes,oneinsixpairswilldifferi

5、ntheirhandedness.Whatthenmakespeopleleft-handedifitisnotsimplygenetic?Otherfactorsmustbeatworkandresearchershaveturnedtothebrainforclues.Inthe1860stheFrenchsurgeonandanthropologist,DrPaulBroca,madetheremarkablefindingthatpatientswhohadlosttheirpowersofspeechasaresultofastroke(abloodclotinthebrain)ha

6、dparalysisoftherighthalfoftheirbody.Henotedthatsincethelefthemisphereofthebraincontrolstherighthalfofthebody,andviceversa,thebraindamagemusthavebeeninthebrainslefthemisphere,Psychologistsnowbelievethatamongrighthandedpeople,probably95percenthavetheirlanguagecentreinthelefthemisphere,while5percenthav

7、eright-sidedlanguage,Left-handers,however,donotshowthereversepatternbutinsteadamajorityalsoSome30percenthaverighthemispherelanguage.DrBrinkman,abrainresearcherattheAustralianNationalUniversityinCanberra,hassuggestedthatevolutionofspeechwentwithright-handedpreference.AccordingtoBrinkman,asthebrainevo

8、lved,onesidebecamespecialisedforfinecontrolofmovement(necessaryforproducingspeech)andalongwiththisevolutioncamerighthandpreference.AccordingtoBrinkman,mostleft-handershavelefthemispheredominancebutalsosomecapacityintherighthemisphere.Shehasobservedthatifaleft-handedpersonisbrain-damagedinthelefthemi

9、sphere,therecoveryofspeechisquiteoftenbetterandthisisexplainedbythefactthatleft-handershaveamorebilateralspeechherstudiesofmacaquemonkeys,Brinkmanhasnoticedthatprimates(monkeys)seemtolearnahandpreferencefromtheirmotherinthefirstyearoflifebutthiscouldbeonehandortheother.Inhumans,however,thespecialisa

10、tioninfunctionofthetwohemispheresresultsinanatomicaldifferences;areasthatareinvolvedwiththeproductionofspeechareusuallylargerontheleftsidethanontheright.Sincemonkeyshavenotacquiredtheartofspeech,onewouldnotexpecttoseesuchavariationbutBrinkmanclaimstohavediscoveredatrendinmonkeystowardstheasymmetryth

11、atisevidentinthehumanbrain.TwoAmericanresearchers,GeschwindandGalaburda,studiedthebrainsofhumanembryosanddiscoveredthattheleft-rightasymmetryexistsbeforebirth.Butasthebraindevelops,anumberofthingscanaffectit.Everybrainisinitiallyfemaleinitsorganisationanditonlybecomesamalebrainwhenthemalefoetusbegin

12、stosecretehormones.GeschwindandGalaburdaknewthatdifferentpartsofthebrainmatureatdifferentrates;therighthemispheredevelopsfirst,thentheleft.Moreover,agirlsbraindevelopssomewhatfasterthanthatofaboy.So,ifsomethinghappenstothebrainsdevelopmentduringpregnancy,itismorelikelytobeaffectedinamaleandthehemisp

13、heremorelikelytobeinvolvedistheleft.Thebrainmaybecomelesslateralisedandthisinturncouldresultinleft-handednessandthedevelopmentofcertainsuperiorskillsthathavetheiroriginsinthelefthemispheresuchaslogic,rationalityandabstraction.Itshouldbenosurprisethenthatamongmathematiciansandarchitects,left-handerst

14、endtobemorecommonandtherearemoreleft-handedmalesthanfemales.Theresultsofthisresearchmaybesomeconsolationtoleft-handerswhohaveforcenturieslivedinaworlddesignedtosuitright-handedpeople.However,whatisalarming,accordingtoMr.CharlesMoore,awriterandjournalist,isthewaythewordrightreinforcesitsownvirtue.Sub

15、liminallyhesays,languagetellspeopletothinkthatanythingontherightcanbetrustedwhileanythingontheleftisdangerousorevensinister.Wespeakofleft-handedcomplimentsandaccordingtoMoore,itisnocoincidencethatleft-hand,oftendevelopastammerastheyarerobbedoftheirfreedomofspeech.However,asmoreresearchisundertakenon

16、thecausesoflefthandedness,attitudestowardsleft-handedpeoplearegraduallychangingforthebetter.IndeedwhenthechampiontennisplayerIndeedwhenthechampiontennisplayerIvanLendlwasaskedwhatthesinglethingimprovehisgame,hesaidhewouldliketobecomealeft-hander.GeoffMaslenQuestions1-7Usetheinformationinthetexttomat

17、chthepeople(listedA-E)withtheopinions(listed1-7)below.Writetheappropriateletter(A-E)inboxes1-7onyouranswersheet.SomepeoplematchmorethanoneDrBrocaBDrBrinkmanCGeschwindandGalaburdaDCharlesMooreEProfessorTurnerExampleAnswerMonkeysdonotshowaspeciesspecificpreferenceforBLeftorright-handedness.1Humanbeing

18、sstartedtoshowapreferenceforright-handednesswhentheyfirstdevelopedSocietyisprejudicedagainstleft-handedBoysaremorelikelytobeAfterastroke,left-handedpeoplerecovertheirspeechmorequicklythanright-handedPeoplewhosufferstrokesontheleftsideofthebrainusuallylosetheirpowerofThetwosidesofthebraindevelopdifferentfunctionsbeforeAsymmetryisacommonfeatureofthehumanbody.