Ling51/Psych56L:AcquisitionofLanguage

Lecture4BiologicalbasesoflanguageacquisitionII

Announcements

Reviewquestionsforbiologicalbasesoflanguageacquisitionavailable

BeworkingonHW2(due10/13/16)–rememberthatcollaborationishighlyencouraged

Thecriticalperiodhypothesis

Critical&sensitiveperiods

“criticalperiodforlanguage”=biologicallydeterminedperiodduringwhichlanguageacquisitionmustoccurinorderforlanguagetobelearnedfullyandcorrectly

Otherbiologicallydetermineddeadlines: -imprinting:chicks&ducklingsfollowfirstthingtheyseeforever(it’s

likelytheirmommy) -visualcellsinhumans:ifcellsforbotheyesdon’treceivevisualinput

duringthefirstyearorsooflife,theylosetheabilitytorespondtovisualinput

Critical&sensitiveperiods

“sensitiveperiod”:biologicallydeterminedperiodduringwhichlearningmustoccurfordevelopmenttohappencorrectly,butdevelopmentcanstilloccurpartiallyafterthisperiod

Critical&sensitiveperiods

Howdowetestforacritical/sensitiveperiodforlanguageacquisition?

Critical&sensitiveperiods

Howdowetestforacritical/sensitiveperiodforlanguageacquisition?

(1)Idealexperiment:deprivechildrenofalllinguisticinputduringthepurportedcritical/sensitiveperiodandseehowlanguagedevelopmentoccurs.

Problem:idealexperimentisn’tsoidealethicallyorlogistically

Critical&sensitiveperiods

Howdowetestforacritical/sensitiveperiodforlanguageacquisition?

Somehistoricalandmoderncasesthathaveunintentionallyprovidedlackoflinguisticinputtochildren:

“wildchildren”:likeVictorofAveyron,OxanaMalayaoftheUkraine

Problem:unclearlackoflanguageissolelyduetolackoflinguisticinput(maybeotherfactors)

http://www.radiolab.org/story/293679-forbidden-experiment/

Critical&sensitiveperiods

Howdowetestforacritical/sensitiveperiodforlanguageacquisition?

Onesuccessstoryforlackoflinguisticinputwithayoungchild:Isabelle

1930s:6-year-oldIsabellediscoveredhiddenawayinadarkroomwithadeaf-mutemotherasheronlycontact.

Shewastaughttospeakandbyage8,appearedtobenormal.Potentialimplication:Isabellediscoveredbeforecritical/sensitiveperiodwasover.

Critical&sensitiveperiods

Howdowetestforacritical/sensitiveperiodforlanguageacquisition?

Amorethoroughstudy:Genie

Critical&sensitiveperiods

Howdowetestforacritical/sensitiveperiodforlanguageacquisition?

Amorethoroughstudy:Genie

1970s:13-year-oldGeniebroughtbyhermothertosocialservicesafterescapingmentallyillfather;untilmother’sescape,hadnolanguageinput(andveryhorrificlivingconditions)

Byage17,shehadafive-year-old’svocabulary,andcouldexpressmeaningsbycombiningwordstogether.

Critical&sensitiveperiods

Howdowetestforacritical/sensitiveperiodforlanguageacquisition?

Amorethoroughstudy:Genie

However…syntacticskillslaggedfarbehind-deficientinbothproductionandcomprehension.

“Mamawashhairinsink.” “Likegorideyellowschoolbus.”“Atschoolscratchface.” “Fathertakepiecewood.Hit.Cry.”“IwantCurtissplaypiano.” “Applesaucebuystore”“Manmotorcyclehave.” “FatherhitGeniecrylongtimeago.”

Dichoticlisteningtasksshowedlanguagewasaright-hemisphereactivityforher(whileit’saleft-hemisphereactivityformostadults).

Critical&sensitiveperiods

Howdowetestforacritical/sensitiveperiodforlanguageacquisition?

Amorethoroughstudy:Genie

PotentialImplication:Geniediscoveredaftercriticalperiodwasover.

However,Geniemayhavehadothercognitivedisabilities…

Critical&sensitiveperiods

Howdowetestforacritical/sensitiveperiodforlanguageacquisition?

Lenneberg(1967):“theonlysafeconclusionstobedrawnfromthemultitudeofreportsislifeindarkclosets,wolves’dens,forests,orsadisticparents’backyardsisnotconducivetogoodhealthornormaldevelopment”

Critical&sensitiveperiods

Howdowetestforacritical/sensitiveperiodforlanguageacquisition?

Anotherstudy:Chelsea(Curtiss1988)

Familybackground:Apartiallydeafwomanincorrectlydiagnosedas“retarded”.Fromalovinghome.

Discoveredatage31,andfittedwithhearingaids

Outcome:Learnedalargevocabulary,butsyntaxandmorphologyworsethanGenie.

Critical&sensitiveperiods

Howdowetestforacritical/sensitiveperiodforlanguageacquisition?

Anotherstudy:Chelsea(Curtiss1988)

SamplespeechfromChelsea:

(1) Thesmallathehat

(2)OrangeTimcarin

(3)IWandabedrivecome

(4)Breakfasteatinggirl

(5)TheyareiscarintheTim

Critical&sensitiveperiods

Howdowetestforacritical/sensitiveperiodforlanguageacquisition?

(2)Lateacquisitionofsignlanguage(ASL):deaf-of-hearingchildrenwhoseparentsdon’tknowsignlanguage.Childrenareeventuallyexposedtosignlanguagewhentheyencounterotherdeafchildren.

Good:individualshavenormalearlychildhoodexperience,exceptforlackoflanguageinput

Critical&sensitiveperiods

Howdowetestforacritical/sensitiveperiodforlanguageacquisition?

Ifacriticalorsensitiveperiodistrue,childrenwholearnearliershouldbebetterthanchildrenwholearnedlater…

Critical&sensitiveperiods

Howdowetestforacritical/sensitiveperiodforlanguageacquisition?

Ifacriticalorsensitiveperiodistrue,childrenwholearnearliershouldbebetterthanchildrenwholearnedlater-thisiswhatNewport(1990)found.Childrenwhowere4to6yearsoldwhenfirstexposedtoASLwerefarsuperiorintheirsignlanguageabilitywhencomparedtochildrenwhowereexposedafterage12.

Critical&sensitiveperiods

Howdowetestforacritical/sensitiveperiodforlanguageacquisition?

Alsoimportant:notjustabouthowlongsignlanguagespeakershadknownthelanguage.Speakerswhohadbeensigningformorethan30yearsshowedthissamedifference:thoseexposedyoungerwerefarsuperiorintheirlanguageskillstothoseexposedwhentheywereolder.

Critical&sensitiveperiods

Howdowetestforacritical/sensitiveperiodforlanguageacquisition?

(3)Lookatsecondlanguagelearning. Why?Childrenwholearnasecondlanguagewhentheyareyoung

oftenbecomeindistinguishablefromtheirnative-bornpeers.Incontrast,peoplewhoareolderhaveverydifferentoutcomes.

Critical&sensitiveperiods

Howdowetestforacritical/sensitiveperiodforlanguageacquisition?

Testingagedifferencesinsecondlanguageacquisition:

-Oyama(1976):testingItalianimmigrantslearningEnglishAgeofarrivalwasbetterpredictorofaccentthanhowmanyyearstheimmigranthadbeenspeakingEnglish

-Oyama(1978):Ageofarrivalwasbetterpredictorofcomprehensionthannumberofyearsspeakingthelanguage(notjustaboutmotorskilllearningability)

Critical&sensitiveperiods

Howdowetestforacritical/sensitiveperiodforlanguageacquisition?

Testingagedifferencesinsecondlanguageacquisition:

Johnson&Newport(1989):testinggrammaticalcompetencyofChinese&KoreannativeslivingintheUS

Heardrecordedvoicesspeakingsentences,andhadtojudgewhethertheywerecorrectornot. “Thefarmerboughttwopigatthemarket.” “Tomisreadingbookinbathtub.”

Second-languageproficiencydependentonageofinitiallanguageexposure(evenwithsamenumberofyearsofexposuretotal)

Morphology:e.g.verbagreementinproduction

(birthon) (4-6yrson) (12yrson)

AgeofInitialLanguageExposure

Tomis/*arereadingbookinbathtub

Second-languageproficiencydependentonageofinitiallanguageexposure(evenwithsamenumberofyearsofexposuretotal)

Age of initial exposurebirthon (4-6yrson) (12yrson)

Second-languageproficiencydependentonageofinitiallanguageexposure–butnotallaspectsaredependent

Basicwordorder:SVO

SubjectVerbObject

Ex:“Penguinslikefish.”

Asopposedto

“Fishpenguinslike”(ObjectSubjectVerb)

Second-languageproficiencydependentonageofinitiallanguageexposure–butnotallaspectsaredependent

Balari&Lorenzo2015:Phonologyandcertainaspectsofmorphosyntax(howwordsandwordpiecescombinetogethertoformphrases)seemtobesetearlierwhilelexicalknowledgeseemstoremainattainableforquitesometime.

AfterMaturationNorelationshipbetweenAgeofArrivalandTestScore

DuringMaturationDeclineinabilitywithmaturation.

Beforeandafterthecritical/sensitiveperiod(sometimescalled“maturation”)

Someevidenceforcritical/sensitiveperiod

Johnson&Newport(1989)alsofoundthatperformancewasnotcorrelatedwith:

■ FormalinstructioninEnglish■ AmountofinitialexposuretoEnglish■ ReportedmotivationtolearnEnglish■ Self-consciousnessinEnglish■ IdentificationwithAmericanculture

Functionalmagneticresonanceimaging(fMRI)studiesconfirmdifferentneuralprocessingforlanguageinindividualswholearnedbeforeage7to8vs.individualswholearnedafterthisage(Kimetal.1997,Dehaeneetal.1997,Wartenburgeretal.2003,Sauretal.2009)

Someevidenceforcritical/sensitiveperiod

Event-relatedpotential(ERP)studiesconfirmdifferingleft-hemispherespecializationforlanguageinindividualswholearnedbeforeage4vs.individualswholearnedbetween4and7vs.individualswholearnedafter7(Weber-Fox&Neville1996,1999,Isel2005)

Someevidenceforcritical/sensitiveperiod Sumup:Critical/sensitiveperiod

■ Languagelearningiscomparativelyeffortlessbeforeage8orso,extremelyeffortfulafter

■ Appliestobothfirstandsecondlanguagelearning■ Appliestospokenandsignedlanguages■ Critical/sensitiveperiodssimilartootherbiologically-

programmedabilitiesinhumansandotherspecies

Sumup:Critical/sensitiveperiod

http://www.quickmeme.com/meme/36f39x/

Criticalvs.sensitive,revisited

Ifthereistrulyacriticalperiodoflanguageacquisition,peoplelearninglanguageafterthisperiodshouldnotsucceedverywellatall(theyshouldbeequallybad).Incontrast,peoplewithinthecriticalperiodshoulddoverywell(theyshouldbeequallynative-like).

Expectation:discontinuousfunctionofperformance

languageacquisitionperformance

age

criticalperiod

However,mostoftheevidencewe’veseen(includingtheonebelow)suggeststhatthereisasmootherdrop-off.(supportforsensitiveperiod)

Hakuta,Bialystok,&Wiley2003

Criticalvs.sensitive,revisitedSeeThiessen,Girard,&Erickson2016forasummaryofstudiessupportingasensitiveinsteadofacriticalperiod.

Criticalvs.sensitive,revisited

“Fromthisperspective,developmentalchangearises,notfromaswitchfromonesetofprocessestoanother,butduetochangesintheeffectivenessofacontinuouslypresentsetoflearningprocesses…whilethe[statisticallearning]processesofextractionandintegrationareactiveacrossthelifespan,theiroutcomewilldifferasafunctionofthelearner’spriorexperienceandmaturationalstate.”

Thepotentialrelationshiptodomain-generalstatisticallearningprocesses:

SeeThiessen,Girard,&Erickson2016forasummaryofstudiessupportingasensitiveinsteadofacriticalperiod.

Criticalvs.sensitive,revisited

Thepotentialrelationshiptodomain-generalstatisticallearningprocesses:“…therearetwomajorfactorsthatmayplausiblybelinkedtochangesinlanguagelearningoutcomesassociatedwithincreasingage.Thefirstisincreasingfamiliarityoflanguage,whichmakesalearnerbeperadaptedtothelanguageswithwhichtheyarefamiliar,butlessabletoadapttonovellanguages.Thesecondfactorismaturaqonalchanges,whichalterboththecogniqvearchitecturesupporqngstaqsqcallearning,andthedegreeofplasqcitywithwhichthelearner’sneurobiologicalorganizaqoncanadapttonovelinput.”

SeeThiessen,Girard,&Erickson2016forasummaryofstudiessupportingasensitiveinsteadofacriticalperiod.

Criticalvs.sensitive,revisited

Whythere’sanageeffect:

“…theadvantageofyoungerlanguagelearnersrelates,inpart,tothefactthatinfantsandyoungchildrenarehighlyadaptablelearners,butnotyetstronglyadaptedtotheirparqcularlinguisqcenvironment.”

Sincewedon’toftenseethissharpdrop-offinperformance,it’smorelikelythereisasensitiveperiodforlearningaspectsoflanguage,ratherthanacriticalperiod.

languageacquisitionperformance

age

criticalperiod

sensitiveperiod

Criticalvs.sensitive,revisited

“…ratherthanpostulatingonecriticalperiodforlanguageacquisition,amoreplausiblehypothesisisthatgrammaticaldevelopmentischaracterizedbyseveralsensitivephases…aphasecanbecharacterizedbyanoptimalperiodfortheacquisitionofthephenomenoninquestion…characterizedbyarelativelyshortonset,followedbyanextendedoptimalperiodandagradualoffset…”–Meisel,2013

Criticalvs.sensitive,revisited

Sowhyareyoungerchildrenbetter?

“Lessismore”hypothesis:Newport1991

Childrencanrememberlessthanadults(andhaveothercognitivelimitations,likelessattention).Perhapslanguageisactuallyeasiertofigureoutiftheinputislimitedtosmallerchunks.Adultsremembermoreandcanstorelongerchunks,whichmakestheiranalyticaltaskharder.

Studiessupportingtheideathatalimitationonthewaychildrenprocessinputleadstobetterlearningperformance:Phillips&Pearl2012,Phillips&Pearlinpress,Pearl,Goldwater,&Steyvers2011,Pearl,Goldwater,&Steyvers2010,Pearl2009,Pearl&Lidz2009,Pearl2008,Pearl&Weinberg2007,Dresher1999,Lightfoot1999,Lightfoot1991

Someexperimentalsupportfortheutilityof“Lessismore”whenlearningaforeignlanguageasanadult:Chin&Kersten2010

AdultslearningFrenchovertwoone-hoursessions-fullsentencesvs.smallphrasesthatincrementallyincreasedlengthtofullsentences(tosimulatechildren’ssteadilyexpandingprocessingabilities)

Adultslearningincrementallyoutperformedadultslearningfromfullsentencesonlanguageproficiencytestsofvocabularyandgrammar.

Sowhyareyoungerchildrenbetter?

Sowhyareyoungerchildrenbetter?

Someexperimentalsupportfortheutilityof“Lessismore”whenlearningalanguageasanadult:Finnetal.2014

Adultsubjectslistenedtoanartificiallanguagetheyweremeanttolearn.Onegroupwastoldtopaycloseattention(activelisteners)whiletheothergrouplistenedmorepassively—theyweredistractedbydoingapuzzleorcoloringwhiletheylistened.

Thepassivelistenersoutdidtheactivelistenerswhenitcametolearningmorphology(howwordscombinetogether)!

Activelisteners:Morecognitiveresourcesfocusedontask.Passivelisteners:Fewercognitiveresourcesfocusedontask.

Sowhyareyoungerchildrenbetter?

Someexperimentalsupportfortheutilityof“Lessismore”whenlearningalanguageasanadult:Finnetal.2014

"Wefoundthatefforthelpsyouinmostsituaqons,forthingslikefiguringoutwhattheunitsoflanguagethatyouneedtoknoware,andbasicorderingofelements.Butwhentryingtolearnmorphology,atleastinthisarqficiallanguagewecreated,it'sactuallyworsewhenyoutry.”—AmyFinn

http://www.sciencedaily.com/releases/2014/07/140721142211.htm

Recap

Thereappearstobeaperiodduringwhichlanguageisacquiredmosteasily-whetherthisisacriticalperiodorsensitiveperiodmayvarydependingonwhatspecificlinguisticknowledgewelookat.

The“lessismore”hypothesisisoneideaforwhychildren’smindsmightbemoresuitedtolanguagelearningthanadults’minds.

Questions?

Youshouldbeabletoanswerupthroughquestion19ofthebiobasesreviewsheet,andupthrough

question19onHW2.