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Morphology and word processing Raymond Bertram Department of Psychology Turku University ’Mieli ja aivot, kieli ja kognitio’: Morphology Ti 25.10.2005,

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Presentation on theme: "Morphology and word processing Raymond Bertram Department of Psychology Turku University ’Mieli ja aivot, kieli ja kognitio’: Morphology Ti 25.10.2005,"— Presentation transcript:

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2 Morphology and word processing Raymond Bertram Department of Psychology Turku University ’Mieli ja aivot, kieli ja kognitio’: Morphology Ti ,

3 Finnish morphology Omnipresent: most words in newspaper are morphologically complex, contain more than one morpheme: HS, : 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

4 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 forms for each noun, about forms for each adjective, forms for each verb  derivation and compounding adds up to the forms EPÄONNISTUMATTOMUUDESSAMMEKOHAN

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6 SAUNA SAUNA’S SAUNAS SAUNAS’

7 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

8 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

9 What is morphology? Some basic concepts Free vs. bound morphemes Stems vs. affixes Affixation types Allomorphs Types of word formation: inflection, derivation, compounding

10 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

11 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’”

12 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)

13 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)

14 Allomorphs Allomorph are variants of a morpheme: one function/meaning, many forms. –stem allomorphy:hattuun vs. hatussa käsi, käde+n, kät+tä, käte+en –suffix allomorphy: metsässä vs. talossa talo+on, metsä+än, talo+i+hin, huonee+seen, huone+i+siin, maahan

15 Inflection, Derivation, & Compounding There are three broad classes of ways to form words from morphemes: inflection and derivation and compounding.

16 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 verb Compositional (meaning can be easily predicted on basis of morphemes) Very productive

17 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] V er] 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

18 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)

19 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

20 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?

21 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?

22 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?

23 In summary, yes morphology does play a role, the question is how and when? Does morphology play a role in daily language processing?

24 Human Morphological Processing syntactic/semantic level mental lexicon: words & morphemes talossa talo ssa mental lexicon: words & morphemes talossa talo ssa letter level t a l o s s a letter level t a l o s s a phoneme level auditory feature level visual feature level How are multimorphemic words represented in the minds of human speakers? segmentation talo+ssa composition talo+ssa

25 mental lexicon: words & morphemes talossa talo ssa mental lexicon: words & morphemes talossa talo ssa letter level t a l o s s a letter level t a l o s s a segmentation talo+ssa route 1 route 2

26 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)

27 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 puhuminen kirjasto talossa koulu kirja -sto puhumaailma talo -ssa minen kirjasto koulumaailma puhu -minen talo -ssa

28 The dictionary question: What’s in the dictionary and what not? Nykysuomen Sanakirja 3a. koulumaailma puhua kirjasto talo kirjasto koulumaailma puhu -minen talo -ssa koulu/maailma, talo/ssa, kirja/sto, puhu/minen

29 How are multimorphemic words represented in the minds of human speakers? My own position 3a. 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

30 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

31 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

32 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

33 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

34 Experimental method Visual lexical decision – testing word length  600 MS  MINASEERI NOYES  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

35 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’ Fbase148 =148 Fsurface 19 > Experiment 2: Base Freq. Exp. (N=20) blonder ‘blonder’ nobeler ‘nobler’ Fbase146 >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

36 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 computation 3. rt mono > rt complex => stor.& comp.

37 Language X Factor Interaction? SUFFIXWFTPRO.HOM.? E.G. 1a. V-teINFYESNO LACHTE 1b. N-ssAINFYESNO TALOSSA 1a. Dutch -te1b. Finnish -ssA BASE SURFACE R T HF LF HF LF MM INF Computation for Finnish and Dutch Inflectional Suffixes

38 Hypo 1: Morphology plays bigger role in Finnish than in Dutch * AS YET it seems that processing complex words in typologically quite different languages such as Finnish and Dutch are co-determined by the same factors. * However, we have been investigating 3 factors in two languages only and the words investigated were bimorphomic.

39 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

40 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

41 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

42 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

43 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

44  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

45 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

46 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

47 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/jänne Short: HF: työ/pukuvs. 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/kahvila Short: HF: kesä/lomavs. LF: veri/koe (respectively: central hospital, book café, summer holiday, blood test)

48 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...

49 Long compounds Short compounds XP1&2, FIRST FIXATION DURATION 1 1st consti- tuent, XP1 whole word, XP2 whole word, XP2 * * 1st consti- tuent, XP1 HF LF HF LFHF LF HF LF HF: tutkimus/retki HF: keskus/sairaala LF: akilles/jänneLF: kirja/kahvila HF: työ/puku HF: kesä/loma LF: hätä/tilaLF: veri/koe

50  Initial involvement of 1 st constituent for long compounds and of whole word form for short compounds!

51 Long compounds Short compounds XP1&2, GAZE DURATION 1st consti- tuent, XP1 whole word, XP2 whole word, XP2 * * 1st consti- tuent, XP1 HF LF HF LFHF LF HF LF * 1 HF: tutkimus/retki HF: keskus/sairaala LF: akilles/jänneLF: kirja/kahvila HF: työ/puku HF: kesä/loma LF: hätä/tilaLF: veri/koe

52  Also later involvement of 1 st constituent for long compounds, but not for short compounds. Short compounds are overall processed in a holistic manner.

53 Support for visual acuity hypothesis: for long compounds initial access of 1 st constituent due to visual acuity benefit of 1 st constituent over the latter part of the word. Use of 1 st 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

54 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

55 5. Ease of segmentation Are there certain cues we use in parsing out constituents

56  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’

57 Vowel Harmony Category 1:AOUBack Vowels Category 2:ÄÖYFront Vowels Category 3:EINeutral Vowels Basic Phonological Rules: or do co-occur:Seppo, enää do not co-occur in a word: talo+ssa, pöly+ssä aou: back vowels äöy: front vowels

58 Vowel Harmony  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 vowels äöy: front vowels

59 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 vowels äöy: front vowels

60 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 vowels äöy: front vowels

61 EXPERIMENT 1, RESULTS Difference between different vowel quality (selkäongelma) and same vowel quality (ryöstöyritys) condition in the following measures: gaze duration (Gaze), 1 st fixation duration (FFD), 2 nd fix. location (SFL), 3 rd fixation location (TFL) different: selkäongelma same: ryöstöyritys aou: back vowels äöy: front vowels

62 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 vowels äöy: front vowels

63 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

64 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.

65 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)

66 Kiitos

67 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”

68 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

69 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

70 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

71 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

72 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

73 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

74 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

75 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-

76 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

77 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

78 SAID (Laine et al. 1994, Niemi et al. 1994)

79 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

80 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)


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