语言学概论-brain-and-language课件

Drainand

LanguagThe

Hu

man

BrainIntroductionThecomplexitiesof

humancognitive

abilities

and

language

acquisition◆Brain

is

the

source

of

humanlanguageandcognition.·Th

emostcomplexorgan

of

the

body

·Cortex(graymatter)a)decision-makingb)memoriesc)grammar

Right

·Whitematter·Contralateral

functionBrainLeft·Which

parts

of

the

brain

areresponsibleforlinguisticabilities?·Franz

Joseph

Gall√Localization√Brainisnot

a

uniform

massThe

LocalizationLanguage√Organology(phrenology)of·

pl

i

hip

between

brain

andlanguage·Languagedisorder

caused

bysaationhasReAdisease

or

trauma·

Broca's

area

v.s.

Wearea·

LateralizationBroca's

area(speech

production)Wernicke's

areaand

memoriesPerceptionsPosterior

languageareaMeaningsofwordsMeaningsofwords(word

recognition)·Mostaphasicsdonot

show

totallanguage

loss.·Thelanguagedisorderis

generally

eal

eto

the

location

of

the

brainBroca'saphasia-injuries

to

theleft

frontal

lobe

Broca's

area□Wernicke'saphasia-injuriestothelefttemporal

lobe

Wernicke's

areagdaematI.Broca'saphasia(agrammaticaphasia)·Syndromes:A.Labored

speechB.Word-finding

difficultiesC.Problemsinformingsentenceswiththe

rules

of

syntaxD.Language

produced

is

often

agrammaticQ:What

is“agrammatic”?A:Itfrequentlylacksarticles,prepositions,pronouns,auxiliary

verbs..

…lacksfunctionwordsThe

omission

of

function

words

in

the

speech

ofagrammaticaphasicsshowsthatfunctionwords

arementallydistinctfrom

contentwords.E.Maytypicallyomitinflectionsthe

past

tense

suffix

-ede.g.I

watched

TV

for

three

hours

this

morning.the

third

person

singular

verb

ending

-se.g.She

likes

playing

the

piano.F.Havedifficultyunderstandingcomplexsentences

inwhichtheycannotrelyontheir

real-worldknowledge.moredifficultyforaphasia

people:e.g.Whichgirldidthe

boy

kiss?less

difficulty

for

aphasia

people:e.g.Which

book

did

the

boy

read?II.Wernicke'saphasia·Wernicke'saphasicscanproducefluentspeechandadhere

to

the

rules

of

syntax.·Syndromes:A.Theirlanguage

isoften

semanticallyincoherent.forkaneedfor

a

schedulewhen

asking

about

poor

visionMywires

don't

hire

right.B.Ha

vedifficultynamingobjectspresentedtothemC.Havedifficulty

choosing

words

in

spontaneousspeech(oftenproducejargon

andnonsensewordsJargon

aphasia·Severe

Wernicke's

aphasia

is

often

referred

toasjargonaphasia.·

Syndrome:substitutenewwordfororiginalwordWordsubstitutionsthataphasicpatientsproduce

alsotellusabouthowwordsareorganized

inthemental

lexicon.soundspool

toolsabletablecrucial

cruciblechair

girlmeaningtableboy·Acquired

dyslexics:people

who

become

dyslexic

after

brain

damage.·Thesimilarphenomenonofword

substitutionsmay

also

happen

to

acquired

dyslexics.(examplesonpage

9)III.Acquired

dyslexicsDyslexia:a

condition

that

makes

it

difficult

forsomeonetoread

and

spell.●·

Thesimilarsyndromeof

theomission

offunction

wordsinthespeech

alsohappensto

acquireddyslexics.(examplesonpage

10)These

errors

show

that

the

mental

lexiconhascontentwordsandfunctionwordsin

differentcompartments.IV.Tip-of-the-tongue

phenomenonTOT·The

tip-of-the-tongue

phenomenon

is

the

failure

toretrieve

a

word

from

memory,combined

withpartialrecall

andthe

feeling

that

retrieval

isimminent.→word-finding

difficulties

inspeaking·

Wordfindingdifficultiesisthefateofmanyaphasics.·Anomia:theinability

tofind

words

you

wishto

speakV.Deaf

Aphasic

patients·Deaf

patients

with

lesions

in

Broca's

areaSyndromes:dysfluentandagrammaticsignproduction·Deaf

patients

with

lesions

in

Wernicke's

areaSyndromes:have

fluent

but

often

semanticallyincoherentsignlanguageConclusion·Deaf

signers

with

damage

to

the

left

hemisphere

show

aphasia

for

sign

language

similarto

thelanguagebreakdowninhearingaphasics.BrainImagingTechnology·

Noninvasivebrainrecordingtechnologies1.Computer

tomography(CT)2.Magnetic

resonance

imaging(MRI)2

Reveallesionsinthelivingbrain

shortlyafterthedamage

occurs.3.Positron

emissiontomography(PET)4.FunctionalMRI(FmrI)5.SinglephotonemissionCT(SPECT)Provideimages

ofthe

brain

in

action.·Otherscanningtechniquesmeasuremetabolicactivityinparticularareas

of

the

brain1.Magnetic

encephalography(MEG)

Thistechniqueshowsus

how

the

healthybrainreactstoparticular

linguisticstimuli.Separationof

the

cognitive

system·Evidence:1.fMRL

&PET

scansDifferential

activation

in

the

normalbrainsinjustthosesitesthatweredamagedintheaphasics.2.neurologicalandbehavioralfindingsLateralization

in

Early

Life·Lateralization

of

language

to

the

lefthemisphere

is

a

process

that

begins

very

earlyinlife.·Infant

as

young

as

one

week

show

a

responseBrain

Plasticity

andhemispherehemispheremusiclanguagerightleft·

Thestudy

found:during

smilinggreateropeningof

theleftside

of

the

mouthduringbabbling

greater

opening

ofthe

rightsideof

the

mouthmorelefthemisphereinvolvement

even

atthisveryearlystageof

productivelanguagedevelopment·the

right

hemispherecantakeoverthe

languagefunctionsthatwouldnormally

reside

inthe

left

hemisphere.·Hemispherectomy1.one

hemisphere

of

the

brain

issurgically

removed2.Treatotherwise

intractablecases

ofepilepsy·Doing

left

hemispherectomyAfter

language

acquisition

has

begunIn

childrenthey

experience

aninitialperiodoffrom

normal

children.In

adults□

Theyinevitablyloseseverelanguagefunctionaphasia

and

then

require

a

linguisticsystem

thatis

virtuallyindistinguishable·

s

ht

topgyriitrgoncesabildentenereusherenaseleftldhro,chirm

pthesoAlfin·Right

hemisphere

playsa

role

intheearlieststagesoflanguageacquisitionhemispherehemispherectomybeforewithbrainlesions·Childrenchildhoodin

therighthemispheretwoyearsofagedon't

developvocabulary

learninglanguage.babblingandprenatal,perinatal,orConclusion·Human

brain

is

essentially

designed

ft·hele,tesyherlttnceaighinsiegdgmmsU

nlanhehetobrain

is

remarkably

resilientandthatif

brain

damage

or

surgery

occursearly

in

life,

normal

left

hemispherefunctionscanbetaken

over

by

therighthemisphere.Spilt

Brainreview:

Whatisthecorpuscallosum?What

istheword"spiltbrain"?an

surgical

technique

to

cut

some

or

allWhat

will

happen

if

people

lose

their

corpuscallosum?nocommunicationbetweentheleftandfunction

independentlyA.Definitioncorpus

callosum

of

a

persontheright

hemispheresAnexperimentonsplit-brain

patientstoshowwhatwillhappento

peoplewhenthe

corpuscallosum

issevered.Whatsignificant

informationwegetfromthisknowing

that

two

hemispheres

of

brain

havedifferentcapacitiesFunction

oftwo

halves:the

right:pattern-matchingtasks,imagination,artawarenessthe

left:

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