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Morphology and word Morphology and word processingprocessingRaymond BertramRaymond Bertram
Department of PsychologyDepartment of Psychology
Turku UniversityTurku University
’Mieli ja aivot, kieli ja kognitio’: Morphology Ti 25.10.2005, 9.45-11.15
Finnish morphology
• Omnipresent: most words in newspaper are morphologically
complex, contain more than one morpheme:
HS, 24.10.2005: Rakennusalan työturvallisuus Suomessa Pohjoismaiden heikoin: Suomessa rakennustyömaiden työturvallisuus on heikompi kuin muissa Pohjoismaissa. Suurten rakennuskonsernien NCC:n ja Skanskan sisäisissä vertailuissa suomalaisten tytäryhtiöiden työmaat ovat muita pohjoismaisia työmaita turvattomampia.
• Rich: many possibilities in combining morphemes
Word forms in the Finnish language: some facts and figures
Affixes that can be added to a Finnish noun:
-number (singular, plural)
-case (over 10)
-possessive suffix (2 x 3)
-enclitic particles (-kin, -pa, -han, -ko, etc.).
about 2 000 forms for each noun, about 6 000 forms for each adjective, 12 000-18000 forms for each verb
derivation and compounding adds up to the forms
EPÄONNISTUMATTOMUUDESSAMMEKOHAN
SAUNA SAUNA’S SAUNAS SAUNAS’
What is morphology?
Study of the internal structure of words:
morph-ology word-s jump-ing
Knowledge of the words of a language can’t be summarized in a finite list: we need to know the principles of word-formation
What is morphology?• Morphology is the study of the way words are built up
from smaller meaning-bearing units, morphemes.– e.g. talo + ssa + ni + kin; house+s
Morphemes…1. cannot be subdivided in smaller meaning-full units.
• ta+lo or ki + n
2. contribute to meaning of a word. • talo ’house’, –ssa ’in’ or –kin ’also’
3. can appear in many different words. • taloon or talonmies or metsäkin
4. do not necessarily coincide with syllable structure. • ta.los.sa
What is morphology?Some basic concepts
• Free vs. bound morphemes
• Stems vs. affixes
• Affixation types
• Allomorphs
• Types of word formation: inflection, derivation, compounding
Morphemes: free vs. bound
• Free morphemes: morphemes that can stand on their own, i.e., can form a word by themselves– lexical morphemes: talo ’house’, car, dog, cat etc. (an
open-ended class: new morphemes can be added)– grammatical morphemes: e.g., determiners the, a, every,
most etc. (a closed class -> all members can be listed)
• Bound morphemes: must be attached to/appear with one or more morphemes to form a word– hatuton ’hatless’ -> *hatu, *ton
Stems vs. affixes
• Many morphologically complex words are composed of stems & affixes
• Stems:– principal components of words– supply the main (lexical) meaning
talo + ssa, house + s
• Affixes:– supply additional meaning
talo + ssa, house + s ”in” ”plurality/’many’”
Affixation types
• Affixes are always bound morphemes.
• Concatenative morphology uses the following types of affixes:– prefixes, e.g. epä- in epä+olennainen, un+real– suffixes, e.g. –ssa in talo+ssa– circumfixes, e.g. German ge- -t in ge+sag+t
([have] said)
• In non-concatenative morphology the stem morpheme is split up. The following types of affixes are used:
– infixes: bili: ‘buy’ => bumili: ‘bought’ (Tagalog);
fan-****-tastic; abso-blooming-lutely
– transfixes, e.g. Hebrew, l+a+m+a+d (he studied), l+i+m+e+d (he taught), l+u+m+a+d (he was taught)
Allomorphs
• Allomorph are variants of a morpheme: one function/meaning, many forms.
– stem allomorphy: hattuun vs. hatussakäsi, käde+n, kät+tä, käte+en
– suffix allomorphy: metsässä vs. talossatalo+on, metsä+än, talo+i+hin, huonee+seen, huone+i+siin,
maahan
Inflection, Derivation, & Compounding
• There are three broad classes of ways to form words from morphemes: inflection and derivation and compounding.
Inflection
Inflection: minimal change due to affixation => new word forms- plural: house -> houses- past tense: work -> worked
Does not alter the category of the stem: worked is a verbCompositional (meaning can be easily predicted on basis of
morphemes)Very productive
Derivation
Derivation: creation of new words by affixation- agentive: to teach -> teacher ’someone who teaches’ - collective: kirja ’book’ -> kirja+sto ’library’ - location: kahvi ’coffee’ => kahvila ’cafe, coffee house’
May change the syntactic category: [teach]Ver]N, [kahvi] N la]N
Meaning is less (un) predictable from the parts – semantically less transparent
Productivity is restricted -> derivational affixes are some times called semi-productive
Compounding
Compounding: creating a words by combining two (or more) real words Compounding is very productive (in both Finnish and English). The simplest case consists of two words concatenated together: auto+talli,
joukkue+henki, In Finnish, the right-hand part is a so-called head that determines the syntactic
category (word class) and the meaning: autotalli is more an auto than a talli The left-hand member is the modifier: morphology+article is an article about
morphology From transparent to opaque: joukkue+henki: the meaning is the ”summed”
meaning of the parts vs. helppo+heikki or red+neck: meaning cannot be directly computed from constituent morphemes
However, even in transparent cases meaning relationship between constituent is pluriform: pine tree (be); music box (make); night flight (in) abortion problem (about)
Does morphology play a role in daily language processing?
Intuitive grounds: we are able to form new words on a daily basis according to morphological principles. We are also able to understand new morphologically complex words that we have never encountered before. Loopvliegen ’walkfly’; neusdoek ’nenäliina’; computer hand; Finishness
Observations:- Speech errors: Speakers make morphologically structured slips: it’s not
only we who have screw looses (for ”screws loose”); easy enoughly (for ”easily enough”).
- Child language: Children overgeneralize during the course of acquisition: *goed (for went)
- Aphasics can produce morphologically structured neologisms: he *jumberfoked and off he went
Experimental evidence (Taft & Forster 1975): Non-word interference: real (bound) stems are rejected as
non-words in lexical decision more slowly than pseud-stems: -vive (revive) vs. –lish (relish)
Same thing happens with non-words that are composed of an illegal combination of an existing prefix and stem (dejoice) take longer to reject than non-words consisting of a pseudo-stem (dejouse)
-> bound stems have an access representation (morphological structure): prefixed words are decomposed in lexical access
Does morphology play a role in daily language processing?
Experimental evidence
Morphological priming
cars primes car: solid effects, long-lasting, facilitation
Orthographic: card – car; variable effects, short-lived, inhibition
Semantic effects: priming for morphologically related, but semantically unrelated words create-creation vs. create-creature (Feldman & Stotko, 1992); Emmorey (1989) priming between permit and submit.
=> Morphological effects cannot be reduced to either form-based or semantic effects
Does morphology play a role in daily language processing?
Experimental evidence
Base frequency effects
• ryhmässä vs. kerhossa• frequency ryhmässä = frequency kerhossa ( n. 35)• frequency ryhmä > much bigger than frequency kerho 9531 vs. 648)
• If frequency of stem/base has an effect, morphological structure has been used in course of processing
• (Taft, 1979; Bradley, 1980; Burani & Caramazza, 1987 Bertram et al., 2000)
Does morphology play a role in daily language processing?
In summary, yes morphology does play
a role, the question is how and when?
Does morphology play a role in daily language processing?
Human Morphological Processing
syntactic/semantic levelsyntactic/semantic level
mental lexicon: words & morphemes talossa talo ssa
mental lexicon: words & morphemes talossa talo ssa
letter levelt a l o s s a
letter levelt a l o s s a phoneme levelphoneme level
auditory feature levelauditory feature levelvisual feature levelvisual feature level
•How are multimorphemic words represented in the minds of human speakers?
segmentationtalo+ssa
compositiontalo+ssa
mental lexicon: words & morphemes talossa talo ssa
mental lexicon: words & morphemes talossa talo ssa
letter levelt a l o s s a
letter levelt a l o s s a
segmentationtalo+ssaroute 1 route 2
Human Morphological Processing
• How are multimorphemic words represented in the minds of human speakers?
1. Full Listing (letter => word)
vs.
2. Morphological Decomposition
(letter => segmentation => morpheme => composition => word)
vs.
3. Dual Storage (1 or 2; 1 and 2)
The morphological processing question: What’s in the mental lexicon and what not?
koulu/maailma, talo/ssa, kirja/sto, puhu/minen
Mental lexicon: 1. all full forms
2. all morphemes
3a. some words fully, some not
3b. 1+2 all words fully, and in morphemes
koulumaailma
puhuminenkirjasto
talossa
koulukirja-sto puhu maailma
talo-ssaminen
kirjastokoulumaailma
puhu -minen
talo
-ssa
The dictionary question: What’s in the dictionary and what not?
Nykysuomen Sanakirja
3a.3a.
koulumaailma
puhuakirjasto
talo
kirjastokoulumaailma
puhu -minen
talo
-ssa
koulu/maailma, talo/ssa, kirja/sto, puhu/minen
How are multimorphemic words represented in the minds of human speakers?
• My own position3a. Dual Storage: 1 or 2, some words full storage, some not:
+ all novel words cannot have obtained full-form storage: computer hand+ all non-novel words have obtained full-form storage: talossa
- all non-novel words storage is morpheme-based as well: talo+ssa
3b. Dual Storage: 1 and 2: all words full & morphemic storage- all novel words cannot have obtained full-form storage: computer hand
+ all non-novel words have obtained full-form storage: talossa+ all non-novel words storage is morpheme-based as well: talo+ssa
3c. Dual Storage: some words morpheme-based storage, some words full & morphemic storage
+ all novel words cannot have obtained full-form storage: computer hand+ all non-novel words have obtained full-form storage: talossa
+ all non-novel words storage is morpheme-based as well: talo+ssa
How are multimorphemic words represented in the minds of human speakers?
• Question: how are storage and processing related• if there is a double representation, do we use them both (talossa +
talossa)
• Question: why do often observe that morphologically complex words are processed holistically
• (that is, why do we often not find morphological effects for existing complex words)
• Question: why do often observe that morphologically complex words are processed via morphemes
• (that is, why do we often only find morphological effects for existing complex words)
• My answer: if you don’t see something, it doesn’t mean that it isn’t there
Dual Route Models
MRM (Morphological Race Model) e.g., Schreuder & Baayen (1995); Bertram, Schreuder & Baayen (2000)- Representations for both full-forms and morphemes- e.g., walked activates /walk/ /ed/ and /walked/ - Recognition is attempted via whole word and morpheme-based representations
simultaneously -> Parallel Dual Route Model- Whether full-form or decompositional route wins is dependent on various
properties of the whole word and the comprising morphemes
mental lexicon: words & morphemestalossa talo ssa
mental lexicon: words & morphemestalossa talo ssa
letter levelt a l o s s a
letter levelt a l o s s a
segmentationtalo+ssaroute 1 route 2
Factors that determine who is winning the race
1. frequency whole word/frequency morphemes ratio* Colé, Segui, Taft, 1997: silmät (70% plural) vs. nenät (10% plural)
2. frequency whole word (aamulla; aphasic patient H.H., Laine)
3. properties of affixes 4. word length X morphology 5. ease of segmentation
mental lexicon: words & morphemestalossa talo ssa
mental lexicon: words & morphemestalossa talo ssa
letter levelt a l o s s a
letter levelt a l o s s a
segmentationtalo+ssaroute 1 route 2
3. The of Storage (full-form processing) and Computation (morpheme-based processing
in Finnish and Dutch: properties of affixes
Bertram, Schreuder & Baayen, 2000: Specific Properties
• Affixal Homonymy => Storage? (‘warmer’-‘rower’; tutkija-lukkoja)
• Productivity => Computation? (warmth-emptiness; kahvila-rahaton)
• Word Formation Type Storage? <=> Computation? derivation vs. inflection => (SAID)
emptiness-laughed; kirjasto-talossa
• Language Storage? <=> Computation? Dutch vs. Finnish
Experimental method• Visual lexical decision – testing word length
600 MS
MINASEERI
NO YES 700 MS
TALO
NO YES 500 MS
E.g., after 20 items per condition, 100 ms or 5% error difference in favour of short words
=> word length has an effect!
SEMINAARI
NO YES
Dependent variables: Reaction time and error rates
VISUAL LEXICAL DECISION: Exp. Methods• 5 Dutch Suffixes and 1 Finnish in The Taft-way (1979)• Experiment 1: Surface Freq. Exp. (N=20)• dieper ‘deeper’ <=> rauwer ‘rawer’ • Fbase 148 = 148 • Fsurface 19 > 1 • ---------------------------------------------------- • Experiment 2: Base Freq. Exp. (N=20) • blonder ‘blonder’ <=> nobeler ‘nobler’ • Fbase 146 > 21 • Fsurface 1.3 = 1.3 • Matching on rel. factors like length & bigramfr.
__________________________________ • If high-freq. condition elicit faster rt’s than low-freq. condition • in Exp. 1, surface freq. exp. => storage• in Exp. 2, base freq. exp. => computation
VISUAL LEXICAL DECISION: Exp. Methods
• The Finnish way (Experiment 1 ) monomorphemic words as baseline
Matching on mm.: hevonen ‘horse’ Lemma, Surface, vs. Bigram Frequency, inf.: talossa ‘house + in’ Vf, Word Length
1. rt mono = rt complex => storage 2. rt mono < rt complex => computation 3. rt mono > rt complex => stor.& comp.
Language X Factor Interaction?
SUFFIX WFT PRO. HOM.? E.G.1a. V-te INF YES NO LACHTE1b. N-ssAINF YES NO TALOSSA
1a. Dutch -te 1b. Finnish -ssA BASE SURFACE
RT
HF LF HF LF MM INF
Computation for Finnish and Dutch Inflectional Suffixes
Hypo 1: Morphology plays bigger role in Finnish than in Dutch
* AS YET it seems that processing complexwords in typologically quite different languages such as Finnish and Dutch are co-determined by the same factors.
* However, we have been investigating 3factors in two languages only and the wordsinvestigated were bimorphomic.
Hypo 2: Specific properties of complex words determine whether lexical access is more or less
holistic
* Indeed, for both languages, the
of Storage and Computation is co-
determined by the INTERPLAY
of factors such as Affixal Homonymy,
Word Formation Type and
Affix Productivity
SEE FIGURE
THE OF STORAGE AND COMPUTATION
productive?
- +storage homonym?
D: A-te , F: N-lA - + inflection? storage
- + D:V-er, A-er F: V-jA, N-jA
computation+ storage computation D: A-heid D: V-te
F: N-stO F: N-ssA
CONCLUSIONS
1. Suffixes should be checked for their properties and be studied one by one
2. Neither Full Parsing or Full listing Models nor Models in which coarse distinctins are made between certain subsets (prefix-suffix; inflection-derivation) can account for the variable data pattern as found here
3. Data pattern is compatible with race models in which the winner is determined by factors as investigated here
Factors that determine who is winning the race
1. frequency whole word/frequency morphemes ratio* Colé, Segui, Taft, 1997: silmät (70% plural) vs. nenät (10% plural)
2. frequency whole word (aamulla; aphasic patient H.H., Laine)
3. properties of affixes 4. word length X morphology 5. ease of segmentation
mental lexicon: words & morphemestalossa talo ssa
mental lexicon: words & morphemestalossa talo ssa
letter levelt a l o s s a
letter levelt a l o s s a
segmentationtalo+ssaroute 1 route 2
fovea: parafovea
1. Is the use of morphemic constituents in processing long compounds due to visual acuity limitations?
Word length X Morphology:Visual acuity and word processing
oppilas/määrä
Eye Movements tracked with Eyelink
Eye movements can give one a good
insight in language processing!
Duration of fixation and length of saccade (among others) tell you something about processing behaviour!
Experimental methods in our lab
fovea: parafovea
Indeed we know that processing of words like vaniljakastike goes by via the constituents vanilja and kastike.
On top of that, early processing of the compound is limited to the first constituent. (HP1998; PHB2000)
Visual acuity and word processing:
vanilja/kastike
Is this purely due to visual acuity limitations?
If morphological structure has a more independent role, processing of shorter compounds SIVU/OVI like should go by via constituents as well!
1
vanilja/kastike
sivu/ovi’side door’
A.
B.
’vanilla sauce’
1
Morphology X Word Length, XP1,2 BH2003
XP1: For long and short compounds, similar manipulation of first constituent frequency.
Long: HF: tutkimus/retki vs. LF: akilles/jänneShort: HF: työ/puku vs. LF: hätä/tila(respectively: research trip, Achilles’ heel, working outfit, emergency situation)
XP2: For long and short compounds, similar manipulation of whole-word frequency.
Long: HF: keskus/sairaala vs. LF: kirja/kahvilaShort: HF: kesä/loma vs. LF: veri/koe(respectively: central hospital, book café, summer holiday, blood test)
Eye movements in our laboratory
* Including words of special interest in single sentences
HF: Saarinen kysyi: “Minkälainen KESKUSSAIRAALA on ...
LF: Saarinen kysyi: “Minkälainen KIRJAKAHVILA on ...
Long compounds Short compounds
XP1&2, FIRST FIXATION DURATION
1
1st consti-tuent, XP1
wholeword, XP2
wholeword, XP2
* *
1st consti-tuent, XP1
HF LF HF LF HF LF HF LF
HF: tutkimus/retki HF: keskus/sairaalaLF: akilles/jänne LF: kirja/kahvila
12 3 2 3HF: työ/puku HF: kesä/lomaLF: hätä/tila LF: veri/koe
1 2 1 2
Initial involvement of 1st constituent for long compounds and of whole word form for short compounds!
Long compounds Short compounds
XP1&2, GAZE DURATION
1st consti-tuent, XP1
wholeword, XP2
wholeword, XP2
* *
1st consti-tuent, XP1
HF LF HF LF HF LF HF LF
*
1HF: tutkimus/retki HF: keskus/sairaalaLF: akilles/jänne LF: kirja/kahvila
12 3 2 3HF: työ/puku HF: kesä/lomaLF: hätä/tila LF: veri/koe
1 2 1 2
Also later involvement of 1st constituent for long compounds, but not for short compounds. Shortcompounds are overall processed in a holistic manner.
• Support for visual acuity hypothesis: for long compounds initial access of 1st constituent due to visual acuity benefit of 1st constituent over the latter part of the word.
• Use of 1st constituent in early and also late processing of long compounds is driven by visual rather than structural principles
Conclusion
1
vanilja/kastike
1
sivu/ovi
Factors that determine who is winning the race
1. frequency whole word/frequency morphemes ratio* Colé, Segui, Taft, 1997: silmät (70% plural) vs. nenät (10% plural)
2. frequency whole word (aamulla; aphasic patient H.H., Laine)
3. properties of affixes 4. word length X morphology 5. ease of segmentation
mental lexicon: words & morphemestalossa talo ssa
mental lexicon: words & morphemestalossa talo ssa
letter levelt a l o s s a
letter levelt a l o s s a
segmentationtalo+ssaroute 1 route 2
5. Ease of segmentation
• Are there certain cues we use in parsing out constituents
Our intuition was that readers must use some
cues that would enhance parsing
(has never been established in reading though)
One cue we considered: ’VOWEL QUALITY’
Vowel Harmony
• Category 1: A O U Back Vowels
• Category 2: Ä Ö Y Front Vowels
• Category 3: E I Neutral Vowels
• Basic Phonological Rules:
• 1 + 3 or 2 + 3 do co-occur: Seppo, enää
• 1 + 2 do not co-occur in a word: talo+ssa, pöly+ssä
aou: back vowelsäöy: front vowels
Vowel Harmony
1 + 2 do not co-occur in a word: talo+ssa, pöly+ssä, except thus in
compounds: e.g. SELKÄ/ONGELMA ’back problem’ different vowel quality at constituent boundary (cb)
though not necessarily, e.g., RYÖSTÖYRITYS ’robbery attempt’
Question: Will a compound word be easier to process (all else equal) if one constituent has front vowels and the other has back vowels?
aou: back vowelsäöy: front vowels
Vowel Quality
•Question: Is a word like
•a. ryöstöyritys with same vowel quality at cb
more difficult to process than a word like
•b. selkäongelma with different vowel quality at cb
aou: back vowelsäöy: front vowels
Examples different vowel type-condition (dvt):
Ystäväni kertoi, että selkä/ongelma oli nyt taaksejäänyttä elämää.
My friend told me, that the back problem was now behind him. same vowel type-condition (svt):
Ystäväni kertoi, että ryöstö/yritys oli jättänyt hänelle pysyviä traumoja.
My friend told me, that the robbery attempt had left him with permanent traumas.
aou: back vowelsäöy: front vowels
EXPERIMENT 1, RESULTS
•Difference between different vowel quality (selkäongelma) and same vowel quality (ryöstöyritys) condition in the following measures: gaze duration (Gaze), 1st fixation duration (FFD), 2nd fix. location (SFL), 3rd fixation location (TFL)
different: selkäongelma
same: ryöstöyritys
Gaze FFD SFL TFLDVT 509 192 8,15 9,73SVT 546 201 7,89 8,36p1 0,02 0,004 0,05 0,000p2 0,05 0,02 0,13 0,000
aou: back vowelsäöy: front vowels
Vowel Quality
• In sum, parsing of processing relatively low-frequency compounds seems to be complicated by vowels of the same quality in the two constituents
• Vowel quality difference across constituents serves as an efficient cue for parsing
aou: back vowelsäöy: front vowels
Factors that determine who is winning the race
1. frequency whole word/frequency morphemes ratio* Colé, Segui, Taft, 1997: silmät (70% plural) vs. nenät (10% plural)
2. frequency whole word (aamulla; aphasic patient H.H., Laine)
3. properties of affixes 4. word length X morphology 5. ease of segmentation
mental lexicon: words & morphemestalossa talo ssa
mental lexicon: words & morphemestalossa talo ssa
letter levelt a l o s s a
letter levelt a l o s s a
segmentationtalo+ssaroute 1 route 2
Conclusions
• There are all kind of factors that determine whether the direct/full-form route or the indirect/parsing/decomposition route dominates the processing of morphologically complex words
• Evidence for dual route model 3c. (some words morpheme-based storage, some words full & morphemic storage)?– Massive priming between morphological relatives
– Factors that we considered logically complicate or facilitate one or the other route
– Morphemic and whole word effects can be observed at the same time
• At any rate, we may say that the role of morphology is not an all-or-nothing affair.
VERY GENERAL CONCLUSION
MORFOLOGIAN ROOLIA EI PITÄISI ALIARVIOIDA
ARVOITUKSELLISIMMISSAKAAN
KIELISSÄ, EIKÄ EDES KIELISSÄ KUTEN HOLLANTI!
(the role of morphology should not be underestimated, neither in the most mysterious languages, nor in languages like Dutch)
Kiitos
Human Morphological Processing
Experiments
Evidence for morpheme-based processing in Finnish: Patient H.H.
Left hemisphere damage aphasia, producing (seemingly) morphological errors in various single-word processing tasks
Examples of HH’s morphological errors:
junasta ”junalle”
eläimessä ”eläin”
puhuja ”puhetta”
Human Morphological Processing
Experiments
Evidence for morpheme-based processing in Finnish: Patient H.H. (Laine et al., 1995)
(1) HH’s morphological difficulties were multimodal (reading, repetition, word production)
Conclusion?
The deficit is of central origin, most probably at the semantic-syntactic level
Human Morphological Processing
Experiments
Evidence for morpheme-based processing in Finnish: Patient H.H.
(2) HH found reading of inflected words extremely difficult while derived words went equally well (or, rather, equally badly) as monomorphemic words. These difficulties were accompanied with increased eye fixations.
Conclusion?
Inflected but not derived Finnish nouns are morphologically decomposed
Human Morphological Processing
Experiments
Evidence for morpheme-based processing in Finnish: Patient H.H.
(3) As an exception to point (2), HH read very high-frequent inflected word forms (e.g., aamu+lla) equally well as comparable monomorphemic words
Conclusion?
Even inflected forms (those of very high frequency) can develop full-form representations in the mental lexicon
Human Morphological Processing
Experiments
Evidence for morpheme-based processing in Finnish: Patient H.H.
(4) Different stem allomorphs (e.g., seiväs, seipää-) were processed equally well.
Conclusion?
Stem allomorphs have their own representations in the mental lexicon
Discussion topic: which factors might affect the way multimorphemic words are stored in the mental lexicon? How would each factor affect the storage? (see, e.g., HH’s results: very high-frequent inflected form full form storage; inflected forms representing other frequency ranges morpheme-based storage)
red+neck vs. air+plane; walk+ed vs. went;
re+search vs. search+er; in+sufficient vs. in+clude;
head+ache –head+quarters
http://www.uoregon.edu/~l150web/weblec1.2.html
Morphological processing: theories Full listing approaches:
Butterworth (1983):- All words are accessed and represented as full-forms, i.e., no morphological
structure even at the central level- Productivity constraint: how are novel complex words recognized? -> assumes
a rule-based back-up procedure that ”jumps in” when new words come along- Rich morphology: how do we do it in Finnish or Turkish where the potential
number of inflected forms alone can be thousands (or tens of thousands) per given lexeme?
Satellite model (e.g., Lukatela et al., 1978)- Separate entry for each inflectional variant- Forms are organized as satellites around the base form (nom. singular)
functioning as a nucleus via which all processing goes
Morphological processing: theories Full listing approaches: Network models (example Bybee, 1995)
Only whole word forms represented However: no list metaphor -> representations are part of an associative network
with interconnections between phonological and semantic levels only (only form and meaning)
No morphology as such: morphological generalizations are seen as emerging from the form-meaning connections (epiphenomenon - no separate level).
Generalizations are gradient and schematic -> no discreet symbolic representations
Connectionist network models are built upon similar assumptions
Morphological processing: theories Obligatory decomposition:
Taft & Forster (1975)- Prefix stripping: in lexical access the prefix is stripped off and ”sent” directly
to the central level; access takes place via the stem- At the central level the legality of the combination is checked -> word is
recognized- Morphologically structured stem-based shared representation for all
morphologically complex words with the particular stem.
in-
Dual Route Models AAM (Augmented Addressed Morphology)
Caramazza et al. (1988)- Representations for both full-forms and morphemes- e.g., walked activates /walk/ /ed/ and /walked/ - All familiar words are accessed via the whole word route -> decomposition
route operational only for novel (unfamiliar) words -> the whole word route always wins
- cf. full-listing with decompositional back-up (Butterworth)
MRM (Morphological Race Model) e.g., Schreuder & Baayen (1995)- Representations for both full-forms and morphemes- e.g., walked activates /walk/ /ed/ and /walked/ - Recognition is attempted via whole word and morpheme-based representations
simultaneously -> Parallel Dual Route Model- Whether full-form or decompositional route wins is dependent on various
properties of stems and affixes, e.g., frequency, semantic transparency, phonological (formal) transparency, affixal homonymy, the ratio with which the form serves as a real and pseudo-affix -> complex interplay
MRM
Three-level interactive activation framework (whole word access) with mechanism for carrying out symbolic computations on representations that become available at different stages (decompositional access)
Activation feedback mechanism Roughly: any factor that complicates morpheme-based access ends up increasing the
activation level for the full forms and enhances whole word access
SAID (Laine et al. 1994, Niemi et al. 1994)
SAID: evidence
Inflected words are decomposed in lexical access, derived words are not• Inflected nouns take longer to recognize in lexical decision than (matched)
monomorphemic nouns -> cost associated with morphological decomposition• An Aphasic patient H.H. had significantly more difficulties in reading inflected
than either derived or monomorphemic nouns (no difference between the latter)
-> inflected words decomposed, derived words not
• However, H.H. read high frecuency inflections (töissä ’at work’) as well as monomorphemics -> high frequency inflected nouns have full-form representations
• Phonological transparency (hattu+ja ’hats’ vs. hatu+ssa ’in a hat’) did not affect either H.H’s performance or lexical decision times -> stem allomorphs have separate representations in the mental lexicon
Thus: inflected nouns are decomposed whereas derived nouns are processed as
wholes
SAID: further evidence
Allomorphy and decomposition free-standing allomorphs prime the respective nominative singular in both
unmasked and masked priming (käde primes käsi)
Derivation Only full-form effects for even productive derived words in –ton (hatuton
’hatless’) in a frequency manipulation experiment
Problems accumulated over the last years: The whole-word frequency (rather than the stem frequency) of an inflected Finnish
word may correlate with reaction time in lexical decision: Affixal homonymy with partitive ending –jA (auto-ja) agentive suffix –jA (opettaja)
In certain sentence contexts, the processing cost associated with inflected Finnish nouns seems to disappear
At least productive derivational endings attached to nonword “stems” (e.g., *rono+nta) can slow down rejection latencies
Suffix allomorphy modulates the processing of derived words (Järvikivi, Bertram & Niemi, in press)