The Anatomy of Language Sydney L

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					                         Ling 411 – 18




The Cortical Representation

    of Verbs and Nouns
         Schedule of Presentations

 Tu Apr 13    Th Apr 15     Tu Apr 20     Th Apr 22
   Delclos     Banneyer      Ruby Tso       Bosley
Planum Temp   Categories      Writing     Synesthesia
                            Rasmussen       Brown
                           2nd language   Lg&Thought
                               Koby           Tsai
                              Music          Tones
                             Mauvais
                           LH-RH anat.
         The “Mental Lexicon”
 A widely used term
   • Usually used by people who think of it as
     a symbol-based system – for example, a
     list of symbolic forms inside the brain
     somewhere
   • Introjection based on a familiar external
     object: the printed dictionary
        (Clearly, a bad idea)
 Connectionist perspective
   • Information corresponding to an external
     “lexical entry” is widely distributed, not
     in one place
              Observation

 Wernicke‟s aphasics (posterior lesion) have
  more difficulty with nouns than verbs and
  Broca‟s aphasics (anterior lesion) have
  more difficulty with verbs than nouns
 Question: If the “mental lexicon” is indeed
  a widely distributed network, how do we
  interpret the apparent anterior/posterior
  differentiation between nouns and verbs?
 Answer: cardinal nodes
               Functional web for a noun
       showing mostly only cardinal nodes




           T
                          C     Cardinal node for the
                                whole functional web
                                 – in angular gyrus
Art                  PR
                                 – likely location for
      PA             V              many nouns
                                 – maybe in temporal
                                    lobe for some nouns
          Functional web for a lexical item
            showing mostly only cardinal nodes



                                             T – Tactile
Maybe there is           T            C
                                             C - Conceptual
also a lemma node                            Art – Articulatory
                                                   Image
                                             P – Phonological
           Art                                   Image
                              P
                                             PA – Primary
                    PA            V
                                                  Auditory
                                             V – Visual
      The lemma hypothesis
 Lemma: term used by Willem Levelt,
  director of the Max Planck Institute
  for Psycholinguistics, Nijmegen, NL
  • And others
 Lemma – cf. morpheme
  • But we have to allow also for complex
    morphemes (e.g., compounds)
      blackbird
      Rice University
      baseball team
 Proposal: Lemma node as cardinal
  node of the functional word web
                     Lemmas
                 Cf. morphemes

 Three layers of language structure
   •   Phonological
   •   Grammatical
   •   Semantic-Conceptual
         With cardinal concept node
 The grammatical layer
   •   Intermediate between phonology and semantics
 Units of the grammatical layer
   •   Morphemes
   •   Complex morphemes (sometimes called lexemes)
         hot dog
         cold turkey
   •   Constructions
Three layers (strata) of language structure

  Phonological
    • Demisyllables, syllables, phonological words
  Lexico-grammatical
    • Lemmas, constructions
    • Lemmas: morphemes, complex morphemes
  Conceptual
    •   a.k.a. semological
  Each stratum has its own structure
          Phonology vis-à-vis Grammar


 Analyzing sisters
   •   Phonological – two syllables
         sis-ters
   •   Grammatical – two morphemes
         sister-s
 Same phonological form, different morphemes
   •   ring n. (e.g., on a finger)
   •   ring v. (what a bell does)
 Same morpheme, different phonological forms
   •   good
   •   bett- (as in bett-er)
Lexico-gramatical vis-à-vis conceptual

 One lemma, different concepts
  •   ring (n.)
       Jewelry on a finger
       as in „ring of thieves‟
       as in ring around the bathtub
       as in boxing ring
 One concept, different lemmas
  • 20
       twenty
       score
   Simple and complex lemmas: hotdog


                             HOTDOG
Concepts         HOT                        DOG



Complex lemma:
 hot dog


Simple lemmas:
 hot, dog              hot            dog
      More complex lemmas

 Combinations of morphemes
  •   sister-s
  •   hot dog
  •   cold turkey
  •   dog-ear-ed
  •   dog-day-s
  •   dog-star
                        Zhong Guo


                              CHINA
              CENTRAL                   KINGDOM



Complex lemma:
 zhongguo


Simple lemmas:
 zhong, guo        zhong              guo
 Coexisting Parallel Structures

              hamburger




Hamburg                                  cheese
                          burger




                burg
  ham
                                   -er
   Terminology: lexeme and lemma

 Lexeme:
  • The information pertaining to a lexical item
  • Represented externally as a dictionary entry
  • Represented cortically as a functional web
      Lexical functional web
 Lemma:
  • The cardinal node of a lexical functional web
               Lemma nodes

 Connectionist perspective
  • Lemma node as cardinal node of the functional
    web for a lexical item (a.k.a lexical functional
    web)
 Locations of lemma nodes
  • Hypothesis: Lemma nodes for different
    grammatical categories are located in
    different cortical areas
      AG or MTG (or SMG?) for noun lemmas
      Frontal lobe for verb lemmas
       Review of Recent Research

1. Research in support of discrete
   representations for nouns and verbs
2. Research in support of common
   representations for nouns and verbs
3. Proposed explanations for distinct
   representations for nouns and verbs in the
   mental lexicon
4. Evidence for/against different accounts
Mental representations of nouns and verbs


 Aphasiology and experiments on
  neurologically intact individuals provide
  evidence for discrete representations of
  nouns and verb lemmas in the cortex
  • Nominal representations in the temporal lobe
      or angular gyrus
  •   Verbal representations in the frontal lobe
Cortical representation of nouns and verbs:
             Types of Evidence

   Dissociations are commonly observed
    in aphasic patients
   Patients with frontal lobe damage
    tend to have trouble with verbs
   Patients with posterior damage tend
    to have trouble with nouns
   Semantic considerations:
     • Processes are controlled in frontal lobe
     • Objects are apprehended in
       temporal/parietal areas
                Broca‟s Aphasia

   Damage to frontal lobe
   Largely intact comprehension
   Nonfluent, agrammatic speech
   “Telegraphic speech” –
    • Abundance of content words (e.g., nouns)
    • Lack of function words (e.g. prepositions)
 Impaired verb processing
    • Bates, Chen, Tzeng, Li & Opie, 1991; Damasio &
      Tranel, 1993; Daniele, Giustolisi, Silveri,
      Colosimo & Gainotti, 1994; Lamb & Zhang, 2002;
      Shapiro & Caramazza, 2003
         Wernicke‟s Aphasia


 Damage to temporal lobe and/or angular
  gyrus and/or SMG
 Impaired comprehension
 Fluent, grammatical, neologistic speech
 Impaired noun processing
  • Bates et al., 1991; Damasio & Tranel, 1993;
    Daniele et al., 1994; Lamb & Zhang, 2002
     Evidence from Aphasia: ROX

 Patient ROX
  • severely agrammatic as a result of cortical
    atrophy
 ROX demonstrated impaired retrieval and
  comprehension of verbs, but normal retrieval
  and comprehension of nouns
 Conclusion: ROX‟s verb impairment with
  relative sparing of nouns indicates that nouns
  and verbs are discretely represented

  McCarthy, R. & Warrington, E. K. (1985). Category specificity in
   an agrammatic patient: The relative impairment of verb
   retrieval and comprehension. Neuropsychologia, 23, 709-727.
    More Evidence from aphasia

 Zingeser & Berndt (1990)
 5 agrammatics, 5 anomics, 5 normals
 Single word elicitation and connected
  speech tasks
  • unambiguous nouns and verbs
  • frequency and length were controlled
 Conclusion: agrammatics have a selective
  verb deficit, whereas anomics have a
  selective noun deficit
Cross-linguistic Evidence from EEG

 Pulvermüller et al. (1996; 1999)
 German-speaking normal subjects
 EEG recordings during a lexical
  decision task
 The 30 Hz responses were stronger
  at recording sites close to the
  motor cortices in response to verbs,
  whereas they were stronger at
  posterior occipital sites over visual
  cortices in response to nouns
     More Cross-linguistic Evidence

 Miceli et al. (1984)
 5 agrammatics, 5 anomics and 10 normal
  controls (Italian speakers)
 Object and action naming tasks
 Agrammatics demonstrated a marked
  deficit in action naming; they were
  selectively impaired in processing verbs
 Conclusion: nouns and verbs are distinct
  word class categories which are organized
  separately within the cortex
      More Cross-linguistic Evidence


 Miceli et al. (1988)
 7 subjects with lesions in various loci
  (Italian)
 Conclusion: not only is the lexicon
  organized into grammatical classes of
  words, but grammatical class information is
  redundantly represented in both input and
  output webs
Cross-linguistic Evidence from Daniele et al. 1994

   Italian
   Patient R.A.
     •   Atrophy of the posterior frontal lobes, including the
         posterior portion of the left inferior frontal gyrus
     •   Verb deficit
   Patient G.G.
     •   Atrophy of the posterior left frontal lobe
     •   Verb deficit
   Patient G.P.
     •   Atrophy of the left temporal lobe
     •   Noun deficit
   Conclusion:
     •   posterior frontal lobe important in the production and
         comprehension of verbs,
     •   temporal lobe important in the production and
         comprehension of nouns
              Contrary Evidence:
           Common Representations?
 Warburton et al., 1996
 PET study
 9 neurologically intact subjects
 Noun and verb retrieval resulted in similar
  activation distributions
 Verb retrieval generated significantly stronger
  activations than noun retrieval in temporal, parietal
  and premotor/prefrontal areas
 This evidence, though not clearly indicative of an
  anatomical dissociation between nominal and verbal
  representations, demonstrates some sort of
  distinction between the processing of nouns and
  verbs
               Flawed studies?

 Wise et al. (1991) and Warburton et al. (1996)
 A flaw in their methodology may account for the
  widely distributed activation
   • The researchers employed a verb generation
     task in which the subjects were asked to
     silently produce verbs that came to mind in
     response to auditorily presented nouns
   • Of course this would result in widely
     distributed brain regions being activated!
   • The brain is processing both nouns and verbs in
     this task
 Any conclusions drawn from this task cannot be
  considered evidence against discrete nominal and
  verbal representations
 Summary of Published Evidence
on representations of nouns and verbs



 Most prior research supports
  the hypothesis of discrete
  representations of nouns and
  verbs in the cortex
   Proposed Explanatory Accounts

 Syntactic/morphological
   •   Shapiro & Caramazza, 2003; Shapiro, Pascual-Leone,
       Mottaghy, Gangitano & Caramazza, 2001
 Semantic-conceptual
   •   McCarthy & Warrington, 1985; Bates et al., 1991;
       Daniele et al., 1994; Pulvermüller et al., 1996;
       Pulvermüller, et al., 1999
 Lexical
   •   Miceli et al., 1984; McCarthy & Warrington, 1985;
       Miceli et al., 1988; Caramazza & Hillis, 1991; Damasio &
       Tranel, 1993; Daniele et al., 1994; Hillis & Caramazza,
       1995; Rapp & Caramazza, 1997; Lamb & Zhang, 2002;
       Laudanna et al., 2002
Syntactic/morphological argument

 Verbs are more closely associated with
  syntax than nouns
   • Verbs are more difficult to process than
     nouns because verbs are inextricably
     associated with syntax
   • Verbs can never “stand alone” in the same
     way nouns can because verbs cannot be
     dissociated from their arguments
 Verbs carry more inflectional morphology
  than nouns (Bates et al., 1991)
 Perhaps the selective verb deficit of an
  agrammatic aphasic may be the cause of
  his/her agrammatism (McCarthy &
  Warrington, 1985)
    Semantic-conceptual accounts

 Prototypical nouns represent objects and
  prototypical verbs represent actions
 Lexical representations for actions are
  located close to the motor cortex
  (frontal lobe) because this is where
  motor planning occurs
 Lexical representations for objects are
  located close to the sensory cortices
  (temporal lobe), presumably because
  objects are known primarily through
  perception
 Query: What about abstract nouns and
  non-action verbs?
Divisions of Primary Motor and Somatic Areas

                                              Primary Somato-
                                              sensory Area
        Primary                        Leg
        Motor Area                    Trunk
                                  Arm
                               Hand
                               Fingers
                              Mouth




           Primary Auditory
                                                       Primary
           Area
                                                       Visual Area
     Higher level motor areas

      Actions per-                       Primary Somato-
      Formed by leg                      sensory Area
                                  Leg
Actions
performed                        Trunk
by hand                      Arm
… by
mouth                     Hand
                          Fingers
                         Mouth




      Primary Auditory
                                                  Primary
      Area
                                                  Visual Area
              Higher level motor areas

                                                     Primary Somato-
Semantic                                             sensory Area
                                              Leg
information
                                             Trunk
for (many)
verbs                                    Arm
                                      Hand
                                      Fingers
                                     Mouth




                  Primary Auditory
                                                              Primary
                  Area
                                                              Visual Area
       Abstract nouns and verbs

 A possible explanation: During language
  acquisition, the first nouns and verbs learned
  are prototypical object nouns and action verbs
 The proximity principle dictates that nouns
  become represented in the temporal lobe, verbs
  in the frontal lobe
 At a later stage in the learning process, when
  non-action verbs and abstract nouns are learned,
  they join the already well-entrenched networks
  dedicated to verb and noun processing located in
  the frontal and temporal lobes, respectively
    Problem with purely semantic account

 Fails to explain how subjects such as ROX (McCarthy &
  Warrington, 1985) are able to mimic actions even though they
  are deficient in the comprehension and production of verbs.
   • The ability to mimic actions demonstrates that the meaning
     of verbs remains intact and unaffected by the neurological
     damage
   • Subjects like ROX provide support for lexical accounts of
     the noun-verb dissociation in that their deficit appears to be
     at the level of the lexeme rather than the conceptual
     representation
 Lamb & Zhang (2010) provide evidence against this account
   • the target jiao-hua „to water flowers‟ elicited the response
     *hua-shui (hua „flower‟, shui „water (n.)‟)
   • Basic meaning is preserved
 Miceli et al. (1984): The agrammatics in this study produced
  semantically relevant nominalizations when naming actions
         Lexical accounts

 Lemma nodes of nouns and verbs
  are differently represented in the
  cortex

 Independent of semantics
               Lexical Account

 The lexical (lemma) account may provide the best
  explanation for the noun-verb dissociation
   • (Miceli et al., 1984; McCarthy & Warrington,
     1985; Miceli et al., 1988; Caramazza & Hillis,
     1991; Damasio & Tranel, 1993; Daniele et al.,
     1994; Hillis & Caramazza, 1995; Rapp &
     Caramazza, 1997; Lamb & Zhang, 2002;
     Laudanna et al., 2002)
 Much of the evidence provided earlier supports
  the probability that cardinal nodes of verb
  lexemes are represented in the left frontal lobe,
  whereas those of nouns are represented in
  posterior cortex
Evidence from Damasio & Tranel (1993)
  AN-1033 and Boswell
    •   impaired noun retrieval
    •   lesions in the left fronto-parietal operculum, posterior
        temporal region, inferior parietal lobule, and left
        anterior and middle temporal lobe
  KJ-1360
    •   impaired verb retrieval
    •   lesion in the left premotor cortex
  Conclusion: there are relatively separate lexical
   systems for nouns and verbs – specifically, the
   left anterior and middle temporal cortices for
   nouns and the left frontal cortices for verbs
  Damasio, A. R., & Tranel, D. (1993). Nouns and verbs are retrieved with
  differently distributed neural systems. Proceedings of the National
  Academy of Sciences of the United States of America, 90,4957-4960.
Evidence from Rapp & Caramazza 1997
 Patient P.B.S.
   • lesion in the left parietal, posterior frontal and
     temporal regions which include both Broca‟s and
     Wernicke‟s areas
   • produced a greater number of written nouns than
     spoken nouns
   • verb use was not normal in either modality, but the
     extent of the spoken verbal deficit was not easily
     determined because of the large number of neologisms
     produced in the place of verbs
 Conclusion: the lexicon is organized so that neurological
  damage can selectively affect knowledge specific to
  grammatical class and modality


 Rapp, B. & Caramazza, A. (1997). The modality-specific organization
 of grammatical categories: Evidence from impaired spoken and
 written sentence production. Brain and Language, 56, 248-286.
  TMS Evidence from Shapiro et al. 2001
 Suppressed the excitability of a portion of the left
  prefrontal cortex in normal subjects through the use
  of repetitive transcranial magnetic stimulation (rTMS)
 Task: produce singular and plural forms of nouns or
  third-person singular and plural forms of verbs; then
  perform same task with pseudo-words
 A delay in the subjects‟ productions of verbs indicated
  that verbs are processed in the left prefrontal cortex,
  whereas nouns are not
 A semantic explanation for the noun-verb dissociation
  does not fully account for the difference because
  both action and non-action verbs were utilized for this
  task
 Also, delay in production of grammatical information
  even when pseudo-words used as verbs
 Evidence from Chinese (Bates et al. 1991)

 Chinese has virtually no inflectional
  morphology for nouns or verbs
 Therefore, if the noun-verb dissociation
  occurs in the speech of Chinese-speaking
  Broca‟s and Wernicke‟s aphasics, the
  dissociation cannot be due to a difference
  in nominal and verbal morphology

    Bates, E., Chen, S., Tzeng, O., Li, P., & Opie, M. (1991). The
    noun-verb problem in Chinese aphasia. Brain and Language,
    41, 203-233.
   Chinese Evidence (Bates et al. 1991)


 6 Broca‟s aphasics, 7 Wernicke‟s aphasics
  and 11 normal controls
 Results indicated that Broca‟s aphasics have
  a selective verb deficit while Wernicke‟s
  aphasics have a selective noun deficit
 The morphological account must be
  dismissed at this point
           Study by Sylvia Chen
 Sylvia Chen, a graduate student of
  Elizabeth Bates at UC San Diego
 Subjects:
  • Ten Broca aphasics
        Reduced fluency and phrase length
        Tendency to omit function words
  •   Ten Wernicke aphasics
        Impaired comprehension
        Fluent or hyperfluent speech
        Marked word-finding difficulties
        Semantic paraphasias
     Nouns and Verbs in Chinese

 Most nouns and verbs are disyllabic
  • Most morphemes are monosyllabic
  • Therefore, the nouns and verbs are compounds
  • Common types: V-N, N-N
 Many have more than two syllables
 Such compounds are learned as units
  • Just like complex lexemes in any language
      Cf. hot dog, Zhong-guo
           Chen‟s experiment

 Patients were tested in their ability to
  name
  • Pictures of objects (nominal compounds)
  • Pictures of common actions (verbal compounds)
 All of the compounds have the form V-N
  • 13 verbal V-N compounds
  • 28 nominal V-N compounds
      Chinese V-N Compounds

 Disyllabic compounds of form V-N
 Some are nouns, some are verbs

 fei v. „to fly‟ + ji n. „machine‟
   • feiji   n. „airplane‟

 chi v. „to eat‟ + fan n. „rice‟
   • chifan    v. „to have a meal‟
          The Experimental Task


 10 Broca‟s aphasics, 10 Wernicke‟s aphasics
 Test with nominal compounds
  • Produce a word to describe a picture of an object
 Test with verbal compounds
  • Produce a word to describe a picture of an action


                      (Sylvia Chen – UCSD dissertation)
  Typical Errors of Broca aphasics
              (for nominal compounds)
 Target             Components         Response

  fei-ji             fei „to fly‟
                                           ji
„airplane‟          ji „machine‟
 wan-ju             wan „play‟
                                           ju
   „toy‟          ju „instrument‟
 shui-yi          shui „to sleep‟
                                           yi
„pajamas‟          yi „clothes‟
  wei-qi         wei „to surround‟        qi-lu
„go (game)‟         qi „chess‟       (lu „strategy‟)
             Summary of findings

 Broca aphasics
   • Difficulty producing verbal components for both
     verbal and nominal compounds
 Wernicke aphasics
   • Difficulty with noun components of verbal compounds
   • More general and varied difficulties with nominal
     compounds
 Responses did not indicate that patients had trouble
  with the semantics of the target items
 This despite the fact that these are compounds and are
  doubtless learned as units by speakers of Chinese
“Potency” of components of compounds
         1. Semantic potency
 Q: Do the meanings of the constituents
  have a bearing on the meaning of the
  composite?
  • understand
  • hot dog
  • blackboard
  • bluebird
 A: Sometimes yes, sometimes no
  • Complex lexemes have a scale of transparency
        From transparent (bluebird)
        To opaque (understand)
  •   Opaque lexemes are known as „idioms‟
Potency of constituents of compunds
      2. Grammatical potency

 Q: Do the grammatical categories of the
  constituents of a compound have a
  bearing on properties of the composite?
 Evidence for positive answer:
   • In Chinese aphasics with impaired verb
     access, nominal compounds are also
     affected if they have verbal
     components
        Evidence for intact semantics
 The subjects did not have difficulty with the
  semantics of the pictures, but only with the
  means of providing linguistic representations
 Example:
  • Target: jiao-hua v. „to water flowers
        jiao v. „to water‟ + hua n. „flower‟
  •   Response: *hua-shui (shui n. „water‟)
  •   Indicates that the (Broca‟s aphasic) patient
      understood the meaning while failing to produce
      the verbal component of the standard compound

                         Sylvia Chen (UCSD dissertation)
       Errors of Broca aphasics
           (for nominal compounds)
 Target          Components        Response

  fei-ji           fei „to fly‟
                                         ji
„airplane‟        ji „machine‟
 wan-ju           wan „play‟
                                         ju
   „toy‟        ju „instrument‟
 shui-yi        shui „to sleep‟
                                         yi
„pajamas‟        yi „clothes‟
  wei-qi       wei „to surround‟        qi-lu
„go (game)‟       qi „chess‟       (lu „strategy‟)
   Conclusions of Chen‟s Experiment


 Verb components and noun components are
  represented differently in the cortex
 This differential representation of the
  components is independent of the
 representation of the compound as a whole,
 even for compounds that are well-
 established and frequently occurring (i.e.
 well entrenched)
         Why is this interesting?

 If a lexeme is learned as a unit, why should
  the components make a difference?
  • If lexemes are stored as units, the grammatical
    categories of their components shouldn‟t matter
 If it is a noun, why should a Broca aphasic
  have trouble with it?
  • Of course, we know from the experiment that it
    is because it has a verbal component
 Moreover, some of these compounds are
  well-entrenched
 How to explain?
 Inferences from Chen‟s Experiment

 Verbal components of compounds are
  represented in the frontal lobe, even
  when they are components of nominal
  compounds (like „airplane‟) that, as nouns,
  are presumably represented in the
  posterior cortex
 The situation can only be understood in
  the context of a distributed network
  (rather than symbolic) representation of
  the linguistic information
Cortical representation of a compound

                Anterior   Posterior

                                       fei-ji n. ‘airplane’


                                                       delay

 fei v. ‘fly’



                                           ji n. ‘machine’
Cortical representation of a compound

            Anterior   Posterior

                                   wan-ju n. ‘toy’

                                               delay

 wan v. ‘play’



                                      ju n. ‘thing’
   Nodes for phonological recognition
       (presumably in Wernicke‟s area)




    wan ‘to play’
                                         wan




                          wa-
demisyllables                     -an
      Or, maybe it works according to the
               new hypothesis

                                  deb

                            ded          den
          [de-]                    de-
                            det          del

                                   dek


      A maxicolumn              Divided into
  (ca. 100 minicolumns)     functional columns
                               (Note that all
English example              respond to /de-/)
     According to the new hypothesis


                                wan1

                         wan2           wang1
       [wa-]                     wa-
                         wai1           wang2

                                 wai2


    A maxicolumn             Divided into
(ca. 100 minicolumns)    functional columns
                            (Note that all
                          respond to /wa-/)
 Nodes for phonological production
     (presumably in Broca‟s area)



                             wan ‘to play’

           PPwan




w-
     -an
Phonological nodes for wan „to play‟



  PPwan                                      PRwan




 w-                            wa-
       -an                             -an

             Internal feedback nodes
             from PP to PR not shown
  Add (cardinal) concept node for wan

PLAY




        PPwan                         PRwan




       w-                 wa-
                -an             -an
Add node for wan-ju „toy‟                          But this proposal
                                                   looks too simple

                           Anterior   Posterior
                                                           wan-ju
      PLAY




                                                                       ju

             PPwan
                                                                PRwan




         w-                                       wa-
                     -an                                  -an
 Why wouldn‟t it work instead like this?

                                   Anterior   Posterior
                                                                wan-ju
              PLAY




                                                                         ju

                     PPwan
                                                                      PRwan




Likely area
of damage        w-                                       wa-
                             -an                                -an
 First try for wan-ju „toy‟                            We need to add
                                                       lemma/morpheme
                                                       nodes
                               Anterior   Posterior
                                                             wan-ju
          PLAY




                                                                        ju

                 PPwan
                                                                   PRwan




Area of
damage?      w-                                       wa-
                         -an                                 -an
       Add lemma node for wan
                with links


Lwan




  PPwan                                  PRwan




 w-
                             wa-
          -an                      -an
  Add concept node for wan

PLAY




Lwan



       PPwan                     PRwan




   w-                wa-
               -an         -an
 Add lemma node for wan-ju „toy‟
                                Anterior Posterior         Lwan-ju

           PLAY


                                                                  Lju
           Lwan



                  PPwan                                            PRwan




Presumed
area of       w-                                     wa-
damage                    -an                               -an
      The beauty of this account

 Consistent with the lack of impairment of
  semantic connections
 The node for the compound is unimpaired
  • Represents an object
  • Therefore, likely to be in posterior cortex
 Consistent with patient‟s ability to
  comprehend speech
 Consistent with diagnosis of Broca‟s aphasia
 The trouble is just with production of the
  verbal component (lemma) of the compound
                 Conclusions

 Nouns and verbs are discretely represented in
  the cortex
 Cardinal lemma and concept nodes for nouns are
  represented in posterior regions (temporal
  and/or parietal)
 Cardinal lemma and concept nodes for verbs are
  represented in anterior regions (frontal lobe)
 The differences between the representations of
  nouns and verbs pertain to their lemma nodes as
  well as to their respective semantic-conceptual
  representations
Reexamine speech in Wernicke aphasia

 Question: How to explain the bizarre
  speech output of Wernicke‟s aphasics
  • Inability to form phonological images
        (already observed)
  •   Inability to monitor output
        (already observed)
  •   But maybe this failure mainly their inability to
      process nouns (and adjectives?)
  •   Add: damage to nearby conceptual area(s)
 Test: analyze some examples of Wernicke‟s
  aphasia speech
Erratic Speech in Wernicke‟s Aphasia


  “I feel very well. My hearing, writing been
  doing well. Things that I couldn‟t hear from.
  In other words, I used to be able to work
  cigarettes. I didn‟t know how….
  Chesterfeela, for 20 years I can write it.”


               From Harold Goodglass
               Understanding Aphasia (1993)
Attempt to describe cookie theft picture

Uh, well this is the ... the /dodu/ of this. This and this
and this and this. These things going in there like that.
This is /sen/ things here. This one here, these two
things here. And the other one here, back in this one,
this one /gesh/ look at this one.

Examiner: Yeah, what's happening there?

(next slide)
    Wernicke‟s aphasia example cont‟d

I can't tell you what that is, but I know what it is, but
I don't now where it is. But I don't know what's under.
I know it's you couldn't say it's ... I couldn't say what
it is. I couldn't say what that is. This shu-- that should
be right in here. That's very bad in there. Anyway,
this one here, and that, and that's it. This is the
getting in here and that's the getting around here,
and that, and that's it. This is getting in here and
that's the getting around here, this one and one with
this one. And this one, and that's it, isn't it? I don't
know what else you'd want.
end

				
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