Lexical Access Routes to Nouns in a Morphologically Rich Language

Journal of Memory and Language 40, 109 –135 (1999) Article ID jmla.1998.2615, available online at http://www.idealibrary.com on

Lexical Access Routes to Nouns in a Morphologically Rich Language Matti Laine, Seppo Vainio, and Jukka Hyo¨na¨ University of Turku, Turku, Finland Most current morphological processing models postulate two lexical access routes, full form and morpheme-based. We explored the nature of the morpheme-based route and its relation to the full-form route by studying recognition of written Finnish nouns. True case-inflection elicited a processing cost, confirming that such forms are recognized via the more demanding morpheme-based route. A processing cost was also observed for morphologically ambiguous nouns (BEARING versus BEAR1ING) and for pseudoambiguous nouns (PUNISH versus PUN(1)ISH). Neither pseudoinflections (BIA(1)S) nor embedded word-initial pseudostems (PET(1)ROL) evidenced processing costs. Our results suggest when the full form route is active, simultaneous activation of the morpheme-based route requires an opportunity for parsing the input string into a stem and a suffix. The pseudoambiguity effect suggests that the morpheme-based route does not test the morphophonological legality of the parsed string. The processing cost associated with morphologically ambiguous and pseudoambiguous nouns indicates that the relationship between the two routes is inhibitory. © 1999 Academic Press Key Words: morphology; lexical access; inflection; mental lexicon.

Word recognition is a remarkable cognitive ability: an adult can recognize tens of thousands of lexical items, even though they often appear in different forms (e.g., view, view1s, view1ing, view1er, pre1view). How are these forms recognized? Early models suggested they could be recognized either as full forms (e.g., Butterworth, 1983) or on the basis of their morphemes (e.g., Taft & Forster, 1975). However, current morphological processing models proThe research reported in this paper was supported by the Academy of Finland (Grant 27774, principal investigator Matti Laine) and by an MCRI (Major Collaborative Research Initiative) grant from the Social Sciences and Humanities Research Council of Canada awarded to Gonia Jarema (Universite de Montreal), director and co-principal investigator; Eva Kehayia (McGill University), co-principal investigator; and Gary Libben (University of Alberta), coprincipal investigator. We are grateful for Marcus Taft for information about his original pseudoinflection experiments and for Harald Baayen, Raymond Bertram, Gary Libben, Jussi Niemi, and Robert Schreuder for helpful discussions. David Balota, Arthur Samuel, Marcus Taft, and anonymous reviewers provided valuable comments on earlier versions of this paper. Fred Karlsson and the Turun Sanomat Company kindly provided us the corpora of written Finnish. Address correspondence and reprint requests to Matti Laine, Department of Neurology (720), University of Turku, FIN-20520 Turku, Finland. E-mail: matti.laine@ utu.fi.

pose that both access routes—full form based and morpheme-based—are available for word recognition (see Baayen, Dijkstra & Schreuder, 1997; Caramazza, Laudanna & Romani, 1988; Frauenfelder & Schreuder, 1992; Niemi, Laine & Tuominen, 1994; Wurm, 1997). It is commonly assumed that the latter route is more demanding, requiring longer recognition times and being more susceptible to errors. Full-form recognition requires the input string to have a corresponding representation stored in the input lexicon. This route is thus available only for a word form that is stored as a single entity. Prime examples would be monomorphemic (base form) words. On the other hand, a typical candidate for morpheme-based access would be a polymorphemic word form that is not very frequent but contains constituent morphemes that have appeared often enough to enable their storage. Medium-to-low frequent inflectional forms would be prime candidates for morpheme-based access. Inflection, as opposed to derivation, does not change the meaning of the stem, and thus would not require full form storage. If the full-form route requires a match between the input string and the access represen-

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tation, how much morphemic information should be included in the input string to activate the morpheme-based route? Models that explicitly address this issue suggest that the mere presence of an affix or an affix-like letter string would be enough to cause discernible effects on word recognition (Taft, 1994; Taft & Forster, 1975). According to this view, even a pseudoaffix (e.g., the final -S in LENS) can impede lexical access due to faulty affix recognition. Lexical decision studies focusing on nonword targets support the view that the presence of an embedded stem or affix in a nonword is enough to activate the morpheme-based access route (e.g., Caramazza et al., 1988; Jarvella & Wennstedt, 1993; Laine, 1996). However, nonword results are necessarily based on unfamiliar stimuli. Moreover, they represent a situation where the full-form recognition route cannot participate in word recognition. Thus, possible interactions between the two routes cannot be observed. In the present study, we aimed to identify conditions under which the morpheme-based access route is activated, and to trace possible interactions of the full form versus the morpheme-based recognition route by employing real, familiar word forms as stimuli. Accordingly, this study can shed light on the constraints of morphological processing in lexical access. Throughout the experiments, we employ nominal case-inflection in a morphologically rich language, Finnish, which is a prime candidate for morphological decomposition. ACTIVATION OF THE MORPHEMEBASED ACCESS ROUTE: EARLIER EVIDENCE The seminal study by Taft and Forster (1975) searched for evidence of morpheme-based access by visual lexical decision experiments with bound stems of prefixed English words. Their essential finding was that bound stems in nonwords (e.g., *JUVENATE, *DISWHELM) delayed negative decisions while bound stem frequencies of ambiguous stems (e.g., VENT) affected positive decisions. Taft and Forster (1975) proposed that lexical access of affixed words is preceded by an automatic prelexical

operation where an affixed word is stripped of its affixes (the prelexical parsing hypothesis). The stem is then used as the entry for lexical access. This model predicts that due to faulty automatic parsing, even pseudoaffixes in real words (e.g., RE- in REPERTOIRE, -S in BIAS) should delay lexical access. Subsequent studies employing real words with pseudoprefixes, derivational pseudosuffixes, and inflectional pseudosuffixes appeared to limit prelexical affix stripping to prefixes and, particularly relevant for the present study, inflectional suffixes (for reviews, see Taft, 1988, 1991). The affix-stripping procedure proposed by Taft and Forster (1975) has been criticized. First, there is some evidence that the effects may be task and/or strategy related. The lexical decision results of Rubin, Becker, and Freeman (1979) suggested that pseudoprefixation effects are under strategic control and depend on the occurrence of prefixed nonwords in an experiment (see also Henderson, Wallis & Knight, 1984). However, Taft (1981) demonstrated the pseudoprefixation effect in a word naming task when nonwords were eliminated. In addition, the effect has been observed in letter cancellation (Smith & Sterling, 1982), eye movements during sentence reading (with pseudoprefixed words eliciting longer first fixations than truly prefixed words; Lima, 1987), and in a recent lexical decision study with controls for strategic and orthographic effects (Pillon, 1998). A second line of criticism comes from lexical statistics. Based on analyses of extensive corpora of Dutch and English, Schreuder and Baayen (1994) argued that pseudoprefixation is so common in these languages that obligatory prefix stripping would be a hindrance to fast and reliable lexical access. Due to problems related to the prelexical parsing hypothesis, Taft (1994) discarded it in his recent interactive activation model. However, he still maintained that the recognition delays elicited by pseudoprefixed and pseudoinflected words are of morphological origin. As regards inflectional suffixes and pseudosuffixes, Taft (1994) suggested that they are automatically parsed off and fed into a syntactic module separate from the lexical system, thereby delaying lexical access.

LEXICAL ACCESS ROUTES TO NOUNS

Another line of evidence for a morphemebased access route comes from lexical decision studies focusing solely on nonwords. By systematically manipulating the morphological structure of nonword targets in Italian, Caramazza et al. (1988) noted a stepwise increase in processing demands: nonwords with partial morphological structure (e.g., *LINKTO, *DRODING) were more demanding than mor phologically nondecomposable (e.g., *DROMAR) nonwords. Nonwords consisting of an (illegal) combination of stem plus suffix (e.g., *MEAT(1)ED) yielded the longest reaction times and highest error rates. All in all, there is evidence for morphemebased access but its nature (prelexical or not?), organization, and relationship to the full form route remain open. It has been assumed that when both access routes are available, they act independently and in parallel (Baayen, Dijstra, & Schreuder, 1997; Frauenfelder & Schreuder, 1992). These questions will be examined in the present study. CENTRAL FEATURES OF FINNISH NOMINAL INFLECTION AND THEIR IMPLICATIONS FOR MORPHOLOGICAL PARSING The language of the present study, Finnish, is particularly suitable for the study of morphological parsing. Finnish is a morphologically rich language with fusional features associated with affixation. Its inflectional system yields over 2000 possible forms for each noun and over 10,000 forms for each verb (Karlsson, 1983). Finnish nouns may be marked for number, case (about 13 in active use), and possession. In addition, so-called clitic particles, conveying certain pragmatic aspects of communication, can be added to the end of the word (e.g., AUTO1I1SSA1MME1KIN “car” 1 “s” (plural marker) 1 “in” (inessive case) 1 “our” (possessive suffix) 1 “even” (clitic particle), meaning “even in our cars”). As regards fusionality, many affixed word forms undergo morphophonological variation and/or stem formation (compare, e.g., AUTO 3 AUTO1SSA versus ILVES “lynx” 3 ¨ ). However, these changes are ILVEKSE1SSA

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in most cases predictable and they can be described by a complex system of rules (Karlsson, 1983). In such a language, morphological parsing of polymorphemic words appears more viable than, for example, in English. Indeed, recent experimental evidence from both normals and aphasics suggests morpheme-based lexical access for case-inflected Finnish nouns: inflected items elicited longer first fixations, slower lexical decision latencies, and higher error rates than comparable monomorphemic (or derived) nouns (Hyo¨na¨, Laine, & Niemi, 1995; Laine, Niemi, Koivuselka¨-Sallinen, Ahlse´n, & Hyo¨na¨, 1994; Laine, Niemi, Koivuselka¨-Sallinen, & Hyo¨na¨, 1995; Niemi et al., 1994). Fusionality has not been shown to affect the speed and accuracy of recognition of inflected forms, leading to the hypothesis that the stem variants have independent representations at the visual input lexicon (Laine et al., 1994; Niemi et al., 1994). All in all, the Finnish nominal system provides a good opportunity to study the functioning of the two access routes in detail. Monomorphemic nouns (assumed to be recognized via the faster full form route) and case-inflected nouns (assumed to be recognized via the more demanding morpheme-based route) provide the points of comparison to the processing of our critical target items. One approach to the morphological parsing issue is to examine its feasibility in light of lexical statistics. As noted earlier, this approach has provided rather unfavorable results as far as obligatory prefix stripping in Dutch and particularly in English is concerned (Schreuder & Baayen, 1994). To obtain comparable data for Finnish, we analyzed the frequencies of most Finnish case inflections and their corresponding pseudosuffixes. All case endings appear both as real (e.g., elative case form AUTO1 ¨ YTA ¨1 STA“car1from”; essive case form PO ¨ NA“table1as”) and as pseudosuffixes (e.g., NA(1)STA “tack”; KAMII(1)NA “stove”). If pseudoaffixation rates were high as observed with many English prefixes, obligatory suffix stripping would be ineffective or even detrimental to lexical access in Finnish. The morphologically disambiguated database

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112 TABLE 1

Parsing Success of Finnish Case Endings: A Lexical Statistical Analysis

Case

Proportion of true inflected forms (types)

Proportion of true inflected forms (tokens)

Genetive Partitive Essive Translative Inessive Elative Illative Adessive Ablative Allative Abessive

.48 .54 .92 .97 .99 .72 .49 .94 .89 .99 .21

.44 .45 .69 .72 .95 .64 .43 .84 .83 .98 .17

we employed is an unpublished computerised corpus of written Finnish with about 1.2 million word tokens.1 Table 1 shows the number of true word-final case-inflected word types or tokens divided by the total number of word types (unique word forms) or tokens (word occurrences) ending with that particular letter string. The only additional criterion is that the possible stem is at least two letters long. As morphological disambiguation performed by an automatic parser was not totally complete (full disambiguation would require contextual analysis; consider, e.g., the word form KALASTA which could be either the elative case form of the word KALA “fish” or the imperative form of the verb “to fish”), the figures should not be considered exact values. Our data indicate that as far as Finnish nominal inflection is concerned, the success rate of straightforward obligatory suffix stripping is generally relatively high, although there is considerable variability between different case forms. Thus, obligatory stripping of case inflections would be more reasonable in Finnish than for example prefix stripping in English. Our lexical statistics indicate that pseudosuffixation 1 This corpus is from a contemporary magazine, and it was kindly provided to us by Professor Fred Karlsson, University of Helsinki.

effects, if they exist, should be observable in a language like Finnish. EXPERIMENT 1 The first visual lexical decision experiment was designed to test whether the presence of a pseudoinflection in monomorphemic nouns (e.g., -S in BIAS) hinders lexical decision. Such an effect would indicate that pseudosuffixes resembling case inflections are sufficient to activate the morpheme-based access route (Taft, 1988; 1994). If this is true, pseudosuffixed words should show a similar processing cost as otherwise comparable case-inflected control words that presumably undergo morphemebased access (Laine & Koivisto, 1998; Niemi et al., 1994). Here also nonword targets (“inflected” versus “monomorphemic”) are interesting as a relative delay in refuting a nonword that carries a case inflection provides support for the assumption that those suffixes have separate access representations (see Laine, 1996, for an earlier study in Finnish). Accordingly, the real word targets in Experiment 1 included pseudosuffixed nominative singular nouns (carrying a word-final letter string similar to a real case inflection, e.g., IKKU(1)NA “window” where nonmorphemic -NA is a homograph of the essive case ending), case-inflected nouns (e.g., VANKI1NA “prisoner1as”), and nominative singular nouns carrying no pseudoinflections (e.g., MITALI “medal”). The nonword targets either carried an inflectional ending ¨ MI1LTA ¨ where LTA ¨ is the ablative (e.g., *VA case marker) or were nonmorphemic (e.g., *NOLTINKA). Method Participants. Twenty-one university students, 10 females and 11 males, served as participants. The participants in this and the following experiments were native speakers of Finnish and had normal or corrected-to-normal vision. None of them reported any neurological illness. Apparatus and procedure. The experiment was run with a PC using a specially designed reaction time program which synchronized stimulus presentation with the raster beam. The par-

LEXICAL ACCESS ROUTES TO NOUNS

ticipants were to decide as quickly and as accurately as possible whether a letter string appearing at the center of a computer screen was a real Finnish word. A centrally presented fixation point (asterisk) preceded each stimulus. Exposure time for the fixation point was 500 ms and the time interval between the fixation point and the stimulus was 1000 ms. Timeout took place 2000 ms after stimulus onset. All stimuli were presented in white lowercase letters on a dark background. Participants were run individually and the test stimuli were preceded by 30 practice trials. In the present and the following experiments, all participants saw all stimuli and the presentation order was randomized individually. Word stimuli. We devised three 20-item sets of words (see Appendix 1). Type 1 consisted of pseudoinflected nouns in nominative singular. The pseudosuffixes corresponded to three caseinflections: elative (-STA), essive (-NA), and partitive (-A).2 Type 2 included case-inflected nouns with the same three case endings and in the same proportions as in Type 1. In this Experiment, the stems of all case-inflected forms were in nominative singular (i.e., base form).3 Type 3 contained nominative singular nouns carrying no pseudoinflections (monomorphemic control words).4 The three sets were matched on average length in letters, average lemma frequency (source: Saukkonen et al., 1979) data base including approximately 400 000 word tokens), average surface frequency (source: Professor Fred Karlsson’s unpublished computerized corpus of written Finnish including 1.2 million word tokens), and average bigram frequency (source: 2

Note that even though the partitive -A case marker appears to be embedded in both elative -STA and essive -NA case markers, phonological restrictions of Finnish state that the final -A in -NA or -STA (or in any other case suffix ending with -A) cannot be a marker for partitive. 3 In subsequent experiments, part of the case-inflected items had non-nominative stem forms. However, as noted earlier, previous systematic studies in Finnish have not revealed any effects of fusionality in the recognition of case-inflected items (Niemi et al., 1994; Laine et al., 1995). 4 Due to length requirements, some items in this as well as other similar sets were lexicalized derivations. Our initial word recognition experiments indicated that even highly productive derivational forms are recognized as fast as monomorphemic nouns during lexical access (Hyo¨na¨, Laine, & Niemi, 1995).

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Mikkonen, 1972) (Table 2).5 In addition to the 60 target stimuli, another set of 60 words of varying length and morphological structure was included as fillers (see Appendix 2). Nonword stimuli. We employed two 20-item sets designed by Laine (1996). They were created from existing nouns by changing one to three letters so that phonotactic rules of Finnish were not violated. In Type 4, nonwords carried ¨ which is one of the the inflectional suffix -LTA two surface forms of the ablative case ending ¨ 1LTA ¨ ). Type 5 included nonaf(e.g., *NELA fixed nonwords, all ending in the three-letter sequence -NKA (e.g., *KAVINKA). Types 4 and 5 were matched by average length in letters (7.45 for both sets), average “stem” (e.g., NELA¨ in *NELA¨ LTA¨ and KAVI in *KAVINKA) bigram frequency (120 for Type 4, 122 for Type 5), and by word-final trigram ¨ and -NKA; frequency (1993 for both -LTA source: Karlsson’s unpublished computerized corpus). In addition to the 40 nonword target stimuli, 80 nonword fillers were included in the stimulus set (see Appendix 2). Results In this and the following experiments, incorrect responses and reaction times longer than three standard deviations above the individual mean latency were replaced by the individual averages for the corresponding conditions prior to data analysis. The rates for errors and replaced long RTs were 3.2 and 0.6%, respectively. Average reaction times and error rates for the present experiment are reported in Table 3. Word results. In the RT analysis, the main effect of stimulus type was significant [F1(2,40) 5 36.95, p , .0001; F 2(2,57) 5 30.86, p , .0001]. Pairwise comparisons indicated significantly longer RTs for the case-inflected than for the monomorphemic control words [by-participant, F(1,20) 5 60.47, p , .0001; by-item, t(57) 5 6.71, p , .0001] or for the pseudoinflected words [by-participant, F(1,20) 5 46.76, p , .0001; by-item, t(57) 5 26.25, p , .0001]. 5 Bigram frequencies are based on absolute values, meaning that their values across experiments vary depending on the corpus employed.

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TABLE 2 Item Characteristics in Experiments 1 and 2

Lemma frequency Surface frequency Length (in letters) Bigram frequency

Pseudoinflected

Inflected

Monomorphemic

65 (73) 17 (20) 6.8 (0.9) 156 (56)

71 (58) 10 (14) 6.9 (0.8) 145 (36)

59 (64) 13 (11) 6.8 (0.7) 142 (41)

Note. Means (standard deviations).

Pseudoinflected and monomorphemic control words did not differ from each other (both F and t , 1). The main effect of stimulus type was significant in the error analysis [F1(2,40) 5 16.60, p , .0001; F 2(2,57) 5 6.94, p , .01]. Pairwise comparisons showed that case-inflected items elicited significantly more errors than the monomorphemic items [by-participant, F(1,20) 5 18.18, p , .0001; by-item, t(57) 5 3.31, p , .01] or pseudoinflected items [by-participant, F(1,20) 5 21.75, p 5 .0001; by-item, t(57) 5 3.14, p , .01], whereas monomorphemic versus pseudoinflected items did not differ from each other (both F and t , 1). Nonword results. Decision latencies for nonwords carrying an inflectional ending were significantly longer than those for nonmorphemic nonwords [F1(1,20) 5 21.46, p , .001; F 2(1,38) 5 13.15, p , .001]. One-way ANOVAs for errors showed a significant effect [F1(1,20) 5 27.04, p , .0001; F 2(1,38) 5 8.21, p , .01], indicating that suffixed nonwords elicited more errors than nonsuffixed nonwords.

when a full-form representation is present, a suffix-like unit alone is not enough to affect lexical access. However, it is possible that the pseudoinflection effect is present under special circumstances, such as when most stimuli in an experiment are inflected (see Rubin et al., 1979, for such a strategic effect). In the first experiment, a bit less than half of the stimuli (110/240, 46%) carried a case-inflection or a pseudosuffix. The second experiment was designed to test whether strategic factors play a role in the recognition of pseudoinflected words. EXPERIMENT 2 In this experiment, we tested whether a high ratio of stimuli carrying a case inflection would bring about the pseudoinflection effect which we failed to observe in the first experiment. Rubin et al. (1979) used this method to show

TABLE 3 Average Decision Latencies and Error Rates for Targets in Experiment 1

Discussion As expected, the results revealed a clearcut processing cost of case inflection, both with real words and with nonwords. These findings confirm the assumption that case-inflected Finnish nouns are recognised via the computationally demanding morpheme-based access route. On the other hand, no processing cost was associated with monomorphemic nouns carrying a pseudoinflection. This does not fit with earlier claims (Taft, 1988, 1994) and suggests that

Condition Real words Pseudoinflected Inflected Monomorphemic Nonwords Nonsuffixed nonwords Case-inflected nonwords

RT in milliseconds (SD)

Error percentage (SD)

671 (131) 771 (161) 665 (138)

1.2 (2.2) 5.7 (4.6) 1.0 (2.0)

841 (189)

1.0 (2.0)

906 (220)

7.1 (5.1)

LEXICAL ACCESS ROUTES TO NOUNS TABLE 4 Average Decision Latencies and Error Rates for Targets in Experiment 2

Condition

RT in milliseconds (SD)

Error percentage (SD)

Pseudoinflected Inflected Monomorphemic

661 (99) 697 (113) 650 (89)

2.0 (3.3) 3.7 (5.7) 1.1 (2.6)

that the prefixation effects observed by Taft and Forster (1975) might be under strategic control. Method Participants. Twenty-three university students, 15 females and 8 males, served as participants. None of them had participated in Experiment 1. They were tested with the same apparatus and procedure as in Experiment 1. Stimuli. We employed the same target words as in Experiment 1: 20 pseudoinflected nouns, 20 case-inflected nouns, and 20 monomorphemic control nouns. The rest of the 240 stimuli consisted of words (60) and nonwords (120) carrying a case-inflection (see Appendix 2). In comparison to Experiment 1, twice as many stimuli (220/240, 92%) had a case-inflection or a pseudosuffix. Results The rates for errors and replaced long RTs were 2.2 and 0.2%, respectively. Average reaction times and errors to the word targets are shown in Table 4. In the RT analysis, the main effect of stimulus type was statistically significant [F1(2,44) 5 17.53, p , .0001; F 2(2,57) 5 4.20, p , .05]. Pairwise comparisons showed that the case-inflected items elicited significantly longer decision latencies than the monomorphemic control words [by-participant, F(1,22) 5 26.56, p , .0001; by-item, t(57) 5 2.76, p , .01] or the pseudoinflected words [by-participant, F(1,22) 5 19.78, p , .001; by-item, t(57) 5 2.15, p , .05]. Pseudoinflected and monomorphemic control words did not differ [by-participant, F(1,22) 5 2.20, p . .1; by-item, t , 1].

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As regards errors, the main effect of stimulus type was significant in the participant analysis [F1(2,44) 5 3.95, p , .05] and marginally significant in the item analysis [F 2(2,57) 5 2.86, p 5 .07]. Pairwise comparisons indicated that case-inflected items elicited more errors than monomorphemic items [by-participant, F(1,22) 5 4.97, p , .05; by-item, t(57) 5 2.35, p , .05]. The comparison between caseinflected and pseudoinflected items was significant in the by-participant analysis only [byparticipant, F(1,22) 5 4.63, p , .05; by-item, t(57) 5 1.56, p . .1]. The pseudoinflected and monomorphemic items did not differ from each other [F(1,22) 5 2.64, p . .1; by-item, t , 1]. Discussion The results suggest that pseudoinflection effects are absent even when morpheme-based analysis is encouraged by a high rate of morphologically decomposable items in the stimulus set. Responses to pseudosuffixed words did not differ from responses to monomorphemic control words even though most of the stimuli carried a case inflection. In contrast, a reliable processing cost for case-inflected nouns was observed, replicating Experiment 1. The RT difference between case-inflected and non-affixed nouns was smaller than in Experiment 1 but remained statistically significant. This suggests a strategic component which was able to facilitate recognition of inflected word forms in Experiment 2 but nevertheless could not override the processing cost associated with the morpheme-based access route. It is also possible that repeated presentation of the same case endings (in Experiment 2, the target cases appeared more often in the nonword fillers than in Experiment 1, see Appendix 2) could have caused some repetition priming which would temporarily enhance the recognition of these inflectional forms. EXPERIMENT 3 In Experiments 1 and 2, the same case endings (elative, essive, partitive) were employed. To ensure that the results obtained were not specific to those case inflections, we devised new sets of stimuli with pseudoinflected and

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TABLE 5 Item Characteristics in Experiment 3

Lemma frequency Surface frequency Length (in letters) Bigram frequency

Pseudoinflected

Inflected

Monomorphemic

37 (38) 6.2 (4.5) 6.4 (1.2) 190 (38)

49 (52) 5.4 (5.2) 6.8 (0.8) 171 (47)

32 (25) 5.7 (4.7) 6.4 (1.0) 172 (31)

Note. Means (standard deviations).

case-inflected nouns carrying genitive, inessive, abessive, and translative endings. The rate of inflected items in the present experiment was 39% (see Appendix 2).

of varying length and morphological structure was included as fillers. A total of 120 nonword fillers were included as well, 57 of them carrying a case inflection (see Appendix 2).

Method

Results

Participants. Twenty university students, 13 females and 7 males, were enrolled as participants. None of them had participated in the previous experiments. The apparatus and the procedure were the same as in Experiment 1 with the exception that in this and subsequent experiments, all stimulus words were written in capitals as some proper nouns were included. Experiments 3 and 5 were run with the same participants in a counterbalanced design within a single test session. There was an approximately three-minute pause between the experiments. Stimuli. Three 20-item sets of words were devised (see Appendix 1). Type 1 included pseudoinflected nouns in nominative singular. The pseudosuffixes corresponded to four caseinflections: genitive (-N), inessive (-SSA), abessive (-TTA), and translative (-KSI). Type 2 included case-inflected nouns with the same three case endings and in the same proportions as in Type 1. Type 3 contained nominative singular nouns with no pseudosuffixes (monomorphemic control words). The three sets were comparable in average length in letters, average lemma frequency (source: Saukkonen et al., 1979), average surface frequency, (source: prof. Fred Karlsson’s unpublished computerized corpus of written Finnish), and average bigram frequency (source: Mikkonen, 1972) (Table 5). In addition to the 60 target stimuli, another set of 60 words

The rates for errors and replaced long RTs were 2.3 and 0.6%, respectively. Average reaction times and errors to the word targets are reported in Table 6. In the RT analysis, the main effect of stimulus type was significant [F1(2,38) 5 29.39, p , .0001; F 2(2,57) 5 11.15, p 5 .0001]. Pairwise comparisons showed significantly longer RTs for the case-inflected words than for the monomorphemic words [by-participant, F(1,19) 5 29.19, p , .0001; by-item, t(57) 5 3.33, p , .01] or for the pseudoinflected words [by-participant, F(1,19) 5 51.99, p , .0001; by-item, t(57) 5 4.56, p , .0001]. The RT advantage for the pseudoinflected items as compared to the monomorphemic items was almost significant in the by-participant analysis but not in the by-item analysis [by-participant, F(1,19) 5 4.25, p 5 .053; by-item, t(57) 5 1.23, p . .1]. TABLE 6 Average Decision Latencies and Error Rates for Targets in Experiment 3

Condition

RT in milliseconds (SD)

Error percentage (SD)

Pseudoinflected Inflected Monomorphemic

608 (102) 673 (103) 625 (116)

2.5 (3.8) 3.5 (5.4) 1.3 (2.2)

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LEXICAL ACCESS ROUTES TO NOUNS TABLE 7 Item Characteristics in Experiment 4

Lemma frequency Surface frequency Length (in letters) Bigram frequency

Stem-embedded

Inflected

Monomorphemic

30 (19) 6.9 (7.5) 6.3 (0.8) 140 (29)

32 (30) 5.8 (6.6) 6.3 (0.8) 147 (40)

31 (23) 6.7 (7.8) 6.2 (0.6) 138 (30)

Note. Means (standard deviations).

The main effect of stimulus type was not significant in the error analysis [F1(2,38) 5 1.61, p . .1; F 2(2,57) 5 2.00, p . .1].

English. However, Andrews (1986) could not replicate that finding.

Discussion

In the present experiment, we tested whether a pseudostem embedded in the initial part of a monomorphemic word (equivalent of BARLEY including BAR and the non-morphemic string LEY) would affect lexical decision in Finnish.

The present results show that the results of Experiments 1 and 2 were not specific to the case endings employed. Instead, case-inflected forms consistently impede lexical decision, whereas pseudoinflection does not exert an effect when compared to monomorphemic items carrying no pseudosuffixes. (In the present experiment, the pseudoinflected items showed an almost significant difference to monomorphemic words but that was present only in the participant analysis and the tendency was toward shorter, not longer, decision time.) At the same time, the nonword results obtained in Experiment 1 showed that pseudoinflection is able to affect recognition when attached to a nonword stem (see also Laine, 1996). Taken together, the present results with words and nonwords suggest that a full-form representation, when available, overrides any effects of pseudoinflection. In the next experiment, we studied whether the presence of a word-initial pseudostem in a monomorphemic (nominative singular) noun could activate the morpheme-based access route. Considering the evidence for left-to-right processing in visual word recognition (e.g., Bergman, Hudson & Eling, 1988; Taft, 1994) and the importance of the stem in lexical access (Taft, 1988), a word-initial pseudostem might affect word recognition even though pseudosuffixation failed to do so. Indeed, Taft (1979) reported a recognition delay for such forms in

EXPERIMENT 4

Method Participants. Twenty-three university students, 21 females and 2 males, participated. None of them had participated in the previous experiments. The apparatus and the procedure were the same as in Experiment 1. Stimuli. Three 18-item sets of words were devised (due to difficulties in finding suitable stimuli, the number of targets was slightly lower than in the other experiments). The targets are given in Appendix 1. Type 1 included nouns in nominative singular carrying a word-initial pseudostem (e.g., KUKKARO ‘purse’ where KUKKA is ‘flower’). In this stimulus set, the average frequencies were higher for the pseudostems than for the full forms (lemma frequency 89 and surface frequency 26 for the pseudostems, with three embedded stems not having a frequency value in this corpus; see Table 7 for comparison). This should enhance the appearance of any pseudostem effects in the experiment. Type 2 included case-inflected nouns in essive, inessive, genitive, and partitive. Type 3 consisted of nominative singular nouns carrying no word-initial or word-final pseudomorphemes (monomorphemic control words). The three sets were comparable in average

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118 TABLE 8

Average Decision Latencies and Error Rates for Targets in Experiment 4

Condition

RT in milliseconds (SD)

Error percentage (SD)

Stem-embedded Inflected Monomorphemic

635 (109) 686 (118) 626 (88)

1.5 (3.1) 8.7 (7.4) 1.5 (3.1)

length in letters, average lemma frequency (source: Saukkonen et al., 1979), average surface frequency (source: prof. Fred Karlsson’s unpublished computerized corpus of written Finnish), and average bigram frequency (source: Mikkonen, 1972) (Table 7). In addition to the 54 targets, 66 real words (18 nominative singular, 48 inflected) and 120 nonwords (60 of them carrying a case-inflection) were included as fillers (see Appendix 2). Results The rates for errors and replaced long RTs were 4.1 and 1.0%, respectively. Average reaction times and errors to the word targets are reported in Table 8. In the RT analysis, the main effect of stimulus type was significant [F1(2,44) 5 21.92, p , .0001; F 2(2,51) 5 6.94, p , .01]. Pairwise comparisons showed that the case-inflected nouns elicited longer RTs than the stemembedded nouns [by-participant, F(1,22) 5 34.01, p , .0001; by-item, t(51) 5 2.96, p , .01] or the monomorphemic control nouns [byparticipant, F(1,22) 5 29.49, p , .0001; byitem, t(51) 5 3.44, p 5 .001]. The comparison between stem-embedded and monomorphemic control nouns was nonsignificant (both F and t , 1). In the error analysis, the main effect of stimulus type was significant [F1(2,44) 5 18.49, p , .0001; F 2(2,51) 5 6.26, p , .01]. Pairwise comparisons showed that the case-inflected items elicited significantly more errors than the stem-embedded [by-participant, F(1,22) 5 18.99, p , .001; by-item, t(51) 5 3.06, p , .01] or the monomorphemic items [by-participant,

F(1,22) 5 24.96, p 5 .0001; by-item, t(51) 5 3.06, p , .01]. The latter two stimulus types did not differ from each other. Discussion The present results indicate that the presence of a word-initial pseudostem in monomorphemic nouns does not hinder lexical decision as compared to otherwise matched monomorphemic nouns with no word-initial pseudomorphemes. The lack of a pseudostem effect is in line with the results reported by Andrews (1986). Once again, real case inflections were recognized more slowly than monomorphemic nouns, showing the consistency of the caseinflection effect in Finnish. All in all, our results indicate that when the full-form route is activated, neither a word-final pseudosuffix (Experiments 1–3) nor a wordinitial pseudostem (Experiment 4) is able to activate the morpheme-based access route. What then is needed to activate the morphemebased access route in the presence of an activated full-form access route? A natural candidate would be a morphologically ambiguous word form presented in isolation. Consider the word BEARING which could be either a nominative singular form (full-form interpretation) or a verb form (morpheme-based interpretation). In the next experiment, we pitted such items against otherwise comparable monomorphemic and case-inflected items. Morphologically ambiguous words should activate both access routes, enabling one to study the relationship between these routes. EXPERIMENT 5 In an attempt to study the relationship between the full-form and the morpheme-based access route, we ran a lexical decision experiment with morphologically ambiguous Finnish nouns. These nouns have both a full form and a morphologically decomposed interpretation (for ¨ example, the full form of the noun SEINA means “wall” but the decomposed form ¨ means “coalfish1as,” i.e., it is the SEI1NA essive case form of the noun SEI).

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LEXICAL ACCESS ROUTES TO NOUNS TABLE 9 Item Characteristics in Experiment 5

Lemma frequency Surface frequency Length (in letters) Bigram frequency

Morphologically ambiguous

Inflected

Monomorphemic

36 (48) 8.6 (6.5) 6.2 (1.1) 159 (37)

37 (34) 6.1 (4.8) 6.5 (0.9) 141 (47)

34 (44) 7.9 (7.7) 6.2 (1.2) 144 (48)

Note. Means (standard deviations).

Method Participants. This experiment was run with the same 21 participants as Experiment 3. Stimuli. We devised three 20-item sets of stimulus words (see Appendix 1). Type 1 included ambiguous nouns that carried conflicting full form versus decomposed meanings. Type 2 included case-inflected nouns with the same case endings and in the same proportions as in Type 1. Type 3 contained monomorphemic nouns in nominative singular (monomorphemic control words). The three sets were comparable in average length in letters, average lemma frequency of the full form (source: Professor Fred Karlsson’s unpublished computerized corpus of written Finnish),6 average surface frequency of the full form (source: Professor Fred Karlsson’s unpublished computerized corpus of written Finnish), and average bigram frequency (source: Mikkonen, 1972) (Table 9). In addition to the 60 target stimuli, another set of 60 words of varying length and morphological structure served as fillers. A total of 120 nonword fillers were included, 61 of them carrying a case inflection (see Appendix 2).

tion times and errors to the word targets are shown in Table 10. In the RT analysis, the main effect of stimulus type was significant [F1(2,38) 5 22.48, p , .0001; F 2(2,57) 5 9.76, p , .001]. Pairwise comparisons showed that the RTs for case-inflected nouns were significantly longer than those for monomorphemic words [by-participant, F(1,19) 5 63.44, p , .0001; by-item, t(57) 5 4.42, p , .0001] or morphologically ambiguous words [by-participant, F(1,19) 5 7.28, p 5 .01; by-item, t(57) 5 2.20, p , .05]. Moreover, the morphologically ambiguous nouns took longer than the monomorphemic control words [by-participant, F(1,19) 5 14.12, p 5 .001; by-item, t(57) 5 2.22, p , .05]. As regards errors, the main effect of stimulus type was significant in the participant analysis [F1(2,38) 5 8.88, p , .001] but not in the item analysis [F 2(2,57) 5 2.01, p . .1]. In the by-participant analysis, pairwise comparisons indicated that the error rate for the monomorphemic words was significantly lower than for the case-inflected words [F(1,19) 5 21.88, p , TABLE 10

Results The rates for errors and replaced long RTs were 3.3% and 0.5%, respectively. Mean reac-

Average Decision Latencies and Error Rates for Targets in Experiment 5

Condition

RT in milliseconds (SD)

Error percentage (SD)

Morphologically ambiguous Inflected Monomorphemic

651 (104) 691 (117) 608 (89)

3.0 (3.8) 5.8 (4.7) 1.5 (3.7)

6

Due to the rarity of ambiguous nouns, we could not employ the limited frequency dictionary of Saukkonen et al. (1979). For the same reason, it was not possible to manipulate the frequencies of the full form versus the decomposed form of the ambiguous nouns. In the present 20 items, the average frequency of the full form was higher than that of the decomposed form.

120

¨ NA ¨ LAINE, VAINIO, AND HYO

.001] or for the morphologically ambiguous words [F(1,19) 5 5.01, p , .05], whereas the latter two did not differ significantly from each other [F(1,19) 5 2.80, p . .1]. Discussion As in Experiments 1 to 4, lexical decision times of case-inflected nouns were significantly longer than those of monomorphemic control nouns. Of particular interest was the finding that decision latencies to the ambiguous nouns were intermediate to the other two stimulus types. That is, ambiguity slowed down recognition but not as much as straightforward case-inflection. Our results thus far indicate that morphological ambiguity but not pseudosuffixation induces a processing cost. We interpret this pattern of results as follows: in the presence of an activated full-form route, the morpheme-based route is activated only when parsing of the letter string into a stem plus suffix is possible. Moreover, activation of both routes slows recognition, indicating that the routes have an inhibitory relationship. As recognition of ambiguous words was nevertheless faster than that of caseinflected words, we assume that the ambiguous words were recognized via the full form route which is slowed due to the inhibitory effect. Our conclusions do not support the view that the two routes are fully independent (Frauenfelder & Schreuder, 1992). Instead, mutual inhibition between the routes would account for the lack of pseudosuffix and pseudostem effects with real words in Experiments 1– 4: the activated fullform route prevented activation of single morpheme-like units in those items. Even though it is commonly assumed that the two access routes function in parallel (e.g., Frauenfelder & Schreuder, 1992; Baayen et al., 1997), an alternative interpretation should be considered. This is based on the possibility that whenever a word form is recognized, only one of the two access routes is active. This would mean that in the present experiment, approximately half of the morphologically ambiguous items would have been recognized solely by the full-form route, whereas the other half would have undergone morpheme-based access. However, a manually performed post hoc disambig-

uation of these forms on the basis of our recently acquired massive computerized corpus of contemporary written Finnish (22.7 million word tokens; Laine & Virtanen, 1996) showed that the full-form interpretation was dominant in as many as 17 of our 20 morphologically ambiguous items. When examining the disambiguation results across the 20 items, the average rate of full form interpretations was 86%. Thus it appears less likely that half of the morphologically ambiguous items were recognized solely by the morpheme-based route and the other half solely by the full form route. All in all, it seems that in the presence of an activated full-form route, an opportunity for morphological parsing into stem plus suffix is needed to activate the morpheme-based route as well. Morphologically ambiguous words fulfill this requirement. In the next experiment, we tested whether this effect extends to morphological pseudoambiguity as well. Consider the verb PUNISH which could be erroneously parsed as a multimorphemic form PUN1ISH (note however that unlike the Finnish target items employed in the next experiment, this example does not involve a stem form that is morphophonologically illegal with the particular suffix. Moreover, the two interpretations represent different word classes, whereas with the Finnish target words, both full form and decomposed interpretations represented nouns). If such forms would also elicit a processing cost, one could conclude that the morpheme-based access route is not concerned with morphophonological legality of stem plus suffix combinations. Instead, legality of stem plus suffix combinations would be analyzed not until later (e.g., via a centrally based fall-back procedure). Such a conclusion would have important implications for the internal organisation of the morphemebased access representations. EXPERIMENT 6 In this lexical decision experiment, we tested whether the processing cost associated with morphological ambiguity (Experiment 5) extended to pseudoambiguous forms. Pseudoambiguity implies that the nominative singular forms in question could be parsed into a stem

LEXICAL ACCESS ROUTES TO NOUNS

121

TABLE 11 Item Characteristics in Experiment 6 Pseudoambiguous

Inflected

Monomorphemic

5.4 (5.9) 2.1 (2.9) 5.5 (0.6) 1294 (534)

7.7 (8.7) 1.7 (2.4) 5.7 (0.8) 1148 (388)

6.0 (5.9) 2.1 (2.8) 5.6 (0.8) 1204 (310)

Morphologically ambiguous

Inflected

Monomorphemic

15 (23) 4.1 (5.2) 6.0 (0.8) 1376 (367)

22 (26) 3.8 (4.9) 6.3 (1.0) 1309 (459)

17 (19) 3.9 (3.8) 6.1 (1.0) 1267 (375)

Lemma frequency Surface frequency Length (in letters) Bigram frequency

Lemma frequency Surface frequency Length (in letters) Bigram frequency Note. Means (standard deviations).

and a suffix but due to morphophonological restrictions, such a combination is illegal. Experiment 6 also included a set of truly morphologically ambiguous nouns in order to replicate the processing cost observed in Experiment 5 with new participants and, for the most part, new stimuli. Method Participants. Twenty university students, 13 females and 7 males, served as participants. None of them had participated in the previous experiments. The apparatus and the procedure were the same as in Experiment 1. Stimuli. We devised six different target sets (see Appendix 1). In this experiment, the source for the lexical data (frequency and bigram values) was our recently acquired unpublished computerized corpus of Laine and Virtanen (1996) which includes 22.7 million word tokens from a major Finnish newspaper. Type 1 included pseudoambiguous nouns. Type 2 included case-inflected nouns with the same case endings and in the same proportions as in Type 1. Type 3 contained monomorphemic nouns in nominative singular (monomorphemic control words), comparable to Type 1. All three sets were comparable in average length in letters, average lemma frequency of the full form, average surface frequency of the full form, and average bigram frequency (Table 11).

Type 4 included morphologically ambiguous nouns that carried conflicting full form versus morphologically parsed meanings. Type 5 included case-inflected nouns with the same case endings and in the same proportions as in Type 4. Type 6 contained monomorphemic nouns in nominative singular (monomorphemic control words) comparable to Type 4. All three sets were comparable in average length in letters, average lemma frequency of the full form, average surface frequency of the full form, and average bigram frequency (Table 11). In addition to the 120 target stimuli, another set of 120 words of varying length and morphological structure served as fillers. Altogether 240 nonword fillers were included, 164 of them carrying a case inflection (see Appendix 2). Results The rates of errors and replaced long RTs were 11 and 0.6%, respectively. Average reaction times and errors to the pseudoambiguous targets and their control words, as well as for the morphologically ambiguous words and their control words, are reported in Table 12. Pseudoambiguous items and their control words. In the RT analysis, the main effect of stimulus type was significant [F1(2,38) 5 30.30, p , .0001; F 2(2,57) 5 13.78, p , .0001]. Pairwise comparisons showed significantly longer RTs for case-inflected words than

¨ NA ¨ LAINE, VAINIO, AND HYO

122 TABLE 12

Average Decision Latencies and Error Rates for Targets in Experiment 6

Condition Pseudoambiguous Inflected Monomorphemic Morphologically ambiguous Inflected Monomorphemic

RT in milliseconds (SD)

Error percentage (SD)

706 (77) 769 (102) 649 (77)

16.0 (11.2) 24.8 (9.4) 6.5 (6.7)

669 (80) 724 (77) 622 (64)

6.8 (5.2) 16.0 (10.7) 1.3 (2.2)

for monomorphemic control words [by-participant, F(1,19) 5 62.74, p , .0001; by-item, t(57) 5 5.23, p , .0001] or for pseudoambiguous words [by-participant, F(1,19) 5 16.34, p , .001; by-item, t(57) 5 23.01, p , .01]. In addition, the pseudoambiguous items elicited longer RTs than the monomorphemic items [byparticipant, F(1,19) 5 13.51, p , .01; by-item, t(57) 5 2.22, p , .05]. The error analysis showed a significant main effect of stimulus type [F1(2,38) 5 25.49, p , .0001; F 2(2,57) 5 4.46, p , .05]. Pairwise comparisons showed that case-inflected items elicited more errors than monomorphemic items [by-participant, F(1,19) 5 52.43, p , .0001; by-item, t(57) 5 2.98, p , .01]. The comparison between case-inflected and pseudoambiguous items was significant in the by-participant analysis only [F(1,19) 5 7.88, p 5 .01; by-item, t(57) 5 21.43, p . .1]. The same was true for the comparison between pseudoambiguous items and monomorphemic items [by-participant, F(1,19) 5 25.50, p 5 .0001; by-item, t(57) 5 1.55, p . .1]. Morphologically ambiguous items and their control words. In the RT analysis, the main effect of stimulus type was significant [F1(2,38) 5 46.42, p , .0001; F 2(2,57) 5 11.55, p 5 .0001]. Pairwise comparisons showed significantly longer RTs for case-inflected words than for monomorphemic control words [by-participant, F(1,19) 5 75.51, p , .0001; by-item t(57) 5 4.80, p , .0001] or for morphologically ambiguous words [by-participant, F(1,19) 5

22.65, p 5 .0001; by-item, t(57) 5 2.54, p 5 .01]. In addition, the ambiguous items elicited longer RTs than the monomorphemic items [byparticipant, F(1,19) 5 33.43, p , .0001; byitem, t(57) 5 2.27, p , .05]. In the error analysis, the main effect of stimulus type was significant [F1(2,38) 5 22.10, p , .0001; F 2(2,57) 5 5.54, p , .01]. Pairwise comparisons showed that case-inflected items elicited more errors than monomorphemic items [by-participant, F(1,19) 5 30.92, p , .0001; by-item, t(57) 5 3.29, p , .01] or morphologically ambiguous items [by-participant, F(1,19) 5 14.05, p 5 .001; by-item, t(57) 5 2.06, p , .05]. The comparison between ambiguous and monomorphemic items was significant in the by-participant analysis only [by-participant, F(1,19) 5 15.43, p , .001; by-item, t(57) 5 1.23, p . .1]. Discussion The present results show that a processing cost is associated both with morphologically ambiguous and pseudoambiguous nouns. The pseudoambiguity effect is interesting because it indicates that the morpheme-based access route does not test the morphophonological legality of the morphologically parsed string. This would greatly simplify the internal organization of the visual input lexicon because one would not need to build in morphophonological rules at this level. Error rates for the pseudoambiguous words and their control items were higher than those for other targets in the present experiments. A probable explanation is that due to the rarity of suitable items, both lemma and surface frequencies of these targets were by far lowest. We have assumed that the processing cost observed with morphological ambiguity and pseudoambiguity is due to mutual inhibition of the full-form and morpheme-based access routes. Another possibility, however, is that recognition is delayed due to a semantic conflict caused by the two interpretations. If anything, polysemy should speed up, not slow down, lexical decision (e.g., Jastrzembski, 1981; Millis & Button, 1989), but in the present case, the source of the semantic conflict is different. With

LEXICAL ACCESS ROUTES TO NOUNS

morphologically ambiguous items, semantic conflict is mediated by two access mechanisms, not by a single, full-form access route as in previously studied ambiguous words like BANK. Accordingly, we attempted to locate the source of the morphological ambiguity (and true case-inflection) effect by examining a task which taps the early, visuoperceptual stages of lexical access. EXPERIMENT 7 In the final experiment we attempted to identify the locus of the processing cost associated with case-inflection and with morphological ambiguity. When employing simple visual lexical decision which encompasses all stages of lexical access, it is difficult to track down the source(s) of an effect. In Experiment 7, we utilized the progressive demasking method introduced by Grainger and Segui (1990). By gradually increasing exposure to the target word in a continuous word pattern mask cycle, the method slows lexical access and is assumed to enhance early, visuoperceptual stages of visual word recognition. As compared to visual lexical decision, progressive demasking has yielded stronger word frequency and orthographic neighborhood frequency effects (Grainger & Jacobs, 1996; Grainger & Segui, 1990; Schreuder & Baayen, 1997) and differential orthographic neighborhood density effects (Carreiras, Perea, & Grainger, 1997) while a presumably semantically based morphological family size effect disappeared (Schreuder & Baayen, 1997). If case inflection and morphological ambiguity slow recognition even in this task, a significant part of the effect must originate from early phases of lexical access and not from semantic ambiguity. Pseudoinflected items were also included in this experiment. Even though no pseudosuffixation effect was present in Experiments 1–3, it is possible that a task tapping early stages of lexical access might reveal morpheme-based activation which would not be visible in lexical decision which involves word form recognition, semantic activation, and decision-making.

123

Method Participants. Twenty university students, 15 females and 5 males, served as participants. None had participated in the previous experiments. Apparatus and procedure. The experiment was run with a PC using a specially designed progressive demasking program. The stimuli were presented in alternation with a pattern mask (a line of hash marks) equal to the stimulus length. Each successive cycle increased the exposure time of the stimulus by 16 ms and decreased the exposure of the pattern mask by 16 ms. On the first cycle, the mask was presented for 284 ms and the stimulus for 16 ms. The cycle length was constant at 300 ms. The cycles followed each other with no pause until the participant pressed the reaction time key indicating that s/he recognized the stimulus emerging from the pattern mask. When the response key was pressed, the screen went blank and the participant wrote down the stimulus s/he had recognized. Stimuli. We employed six different target sets taken from our earlier experiments. Type 1 included pseudoinflected nouns. Type 2 included case-inflected nouns with the same case endings and in the same proportions as in Type 1. Type 3 contained monomorphemic nouns in nominative singular (monomorphemic control words), comparable to Type 1. These three sets were the same as in Experiment 3 and thus they were comparable in average length in letters, average lemma frequency of the full form, average surface frequency of the full form, and average bigram frequency. Type 4 included morphologically ambiguous nouns that carried conflicting full form versus morphologically parsed meanings. Type 5 included case-inflected nouns with the same case endings and in the same proportions as in Type 4. Type 6 contained monomorphemic nouns in nominative singular (monomorphemic control words) comparable to Type 4. Types 4 – 6 were taken from Experiment 6 and thus they were comparable in average length in letters, average lemma frequency of the full form, average sur-

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124 TABLE 13

Average Decision Latencies and Error Rates for Targets in Experiment 7

Condition Pseudoinflected Inflected Monomorphemic Morphologically ambiguous Inflected Monomorphemic

RT in milliseconds (SD)

Error percentage (SD)

958 (178) 1116 (324) 981 (194)

0.8 (1.8) 6.5 (5.4) 1.5 (2.4)

1091 (278) 1174 (367) 1018 (239)

3.5 (5.6) 11.8 (8.5) 2.0 (3.4)

face frequency of the full form, and average bigram frequency. Results The rates of errors and replaced long RTs were 4.4 and 1.8%, respectively. Mean reaction times and errors are shown in Table 13. Pseudoinflected items and their control words. In the RT analysis, the main effect of stimulus type was significant [F1(2,38) 5 13.29, p , .0001; F 2(2,57) 5 10.04, p , .001]. Two of the three pairwise comparisons were statistically significant: case-inflected words yielded longer RTs than monomorphemic control words [by-participant, F(1,19) 5 13.74, p , .01; by-item, t(57) 5 3.56, p , .001] or pseudosuffixed control words [by-participant, F(1,19) 5 14.62, p 5 .001; by-item, t(57) 5 4.14, p 5 .001]. Pseudoinflected and monomorphemic items did not differ significantly from each other [by-participant, F(1,19) 5 1.96, p . .1; by-item, t , 1). In the error analysis, the main effect of stimulus type was significant [F1(2,38) 5 20.68, p , .0001; F 2(2,57) 5 6.86, p , .01]. Pairwise comparisons showed significantly higher error rates for the case-inflected words than for the monomorphemic control words [by-participant, F(1,19) 5 21.11, p , .001; by-item, t(57) 5 2.96, p , .01] or for the pseudoinflected words [by-participant, F(1,19) 5 22.29, p 5 .0001; by-item, t(57) 5 3.41, p 5 .001]. The difference in error rates between pseudoinflected and

monomorphemic items failed to reach significance [by-participant, F(1,19) 5 3.35, p 5 .08; by-item, t , 1]. Morphologically ambiguous items and their control words. In the RT analysis, the main effect of stimulus type was significant [F1(2,38) 5 13.21, p , .0001; F 2(2,57) 5 7.67, p 5 .001]. Pairwise comparisons showed longer decision latencies for morphologically ambiguous items than for monomorphemic control items but this difference was significant in the byparticipant analysis only [by-participant, F(1,19) 5 11.60, p , .01; by-item, t(57) 5 1.51, p . .1]. RTs for morphologically ambiguous items were shorter than for case-inflected control words [by-participant, F(1,19) 5 5.89, p , .05; by-item, t(57) 5 2.38, p , .05]. The difference between monomorphemic and caseinflected control words was highly significant [by-participant, F(1,19) 5 14.62, p 5 .001; by-item, t(57) 5 3.89, p , .001]. In the error analysis, the main effect of stimulus type was significant [F1(2,38) 5 16.14, p , .0001; F 2(2,57) 5 9.14, p , .001]. Pairwise comparisons showed significantly higher error rates for case-inflected words than for monomorphemic control words [by-participant, F(1,19) 5 22.25, p , .001; by-item, t(57) 5 3.97, p , .001] or for ambiguous words [byparticipant, F(1,19) 5 18.29, p , .001; by-item, t(57) 5 3.36, p 5 .001]. The error rates for ambiguous versus monomorphemic items did not differ from each other (F 5 1, t , 1). Discussion The results obtained by the progressive demasking technique are similar to our lexical decision results: case-inflected words are recognized slower than monomorphemic words or pseudoinflected words, whereas the recognition time of morphologically ambiguous words is intermediate between case-inflected and monomorphemic words. This suggests that the source of the morphological ambiguity effect, as well as the true case-inflection effect, is mainly located at the early stages of lexical access, that is, associated with the functioning of the lexical access routes. Furthermore, the lack of pseudoinflection effect in progressive demasking con-

LEXICAL ACCESS ROUTES TO NOUNS

firms that mere pseudoinflection is unable to elicit any significant activation of the morpheme-based access route when the full form route is active. GENERAL DISCUSSION The results are consistent with our initial assumption that the morphological operation critical to our study, nominal case-inflection in Finnish, is a prime example of morphological decomposition. As compared to otherwise comparable monomorphemic nouns, true case-inflected nouns consistently elicited a processing cost in both visual lexical decision (Experiments 1– 6) and a task tapping early stages of visual word recognition (progressive demasking; Experiment 7). These results are in line with earlier experimental evidence in Finnish, obtained with both normal individuals (Niemi et al., 1994; Hyo¨na¨ et al., 1995; Laine, 1996; Laine & Koivisto, 1998) and with single aphasic patients (Laine et al., 1994, 1995). Given the morphological richness of Finnish, morphemebased organization for inflected forms appears reasonable. It enables a Finnish speaker to recognize and interpret unfamiliar inflected forms which are probably encountered daily. In line with the real word results was the finding that nonwords carrying an ending resembling a case suffix elicited a processing cost (Experiment 1). This result supports the idea that case suffixes have independent representations in the visual input lexicon (Laine, 1996) and that they can be activated when a full-form representation is not available. In contrast to the consistent effect elicited by true case inflection, monomorphemic words carrying a similar ending (pseudosuffix) or a word-initial pseudostem did not have any observable effect on lexical access (Experiments 1 to 4 and 7). Thus in the presence of an activated full-form input representation, a pseudosuffix or a pseudostem is not enough to activate the morpheme-based access route. The lack of a pseudoinflection effect is not in line with the English data reviewed by Taft (1988) showing a significant effect of pseudoinflection in real words. Taft (personal communication, 1995) pointed out methodological problems in his

125

original study. Due to difficulties in obtaining suitable stimuli, some of the pseudoinflected items were very rare (e.g., SAMOY(1)ED, WORST(1)ED) and only few participants knew them. It is possible that this factor affected the original results. In the present experiments employing pseudoinflection, error rates were low and the stimuli were rigorously selected and controlled for lemma frequency, surface frequency, length, bigram frequency, and distribution of suffixes/pseudosuffixes used. As regards the lack of pseudostem effect, our results contrast with those of Taft (1979). However, our results are consistent with the lexical decision results of Andrews (1986) and the segment-shifting results of Feldman, Frost, and Pnini (1995; Experiment 1), which did not reveal any pseudostem effects. Although a pseudosuffix or a pseudostem is not enough to activate the morpheme-based route when the full-form route is active, the results of Experiment 5 indicated that morphological ambiguity does affect lexical decision. Our interpretation is that, under the influence of the activated full-form route, parsing of the input string into a stem and suffix is needed to elicit discernible effects of morpheme-based activation. The progressive demasking task (Experiment 7) indicated that a significant source of this effect is at rather early stages of lexical access. Because morphological ambiguity had a processing cost, we conclude that the relationship between the full-form route and the morpheme-based route is inhibitory rather than facilitatory or neutral. The processing cost associated with morphologically ambiguous nouns is not in line with the hypothesis of statistical facilitation in the recognition of morphologically complex words (Frauenfelder & Schreuder, 1992). Statistical facilitation would require full independence of the two parallel lexical access routes and would imply that recognition of morphologically ambiguous nouns should be faster than that of monomorphemic control words. Instead, our results suggest that the two access routes are truly competitive in the sense that they are able to inhibit each other. This is not a unique finding in morphological research: using a priming paradigm, Laudanna,

126

¨ NA ¨ LAINE, VAINIO, AND HYO

Badecker and Caramazza (1989, 1992) reported competitive inhibition among homographic word roots in inflected (but not derived) forms. Recent studies in auditory processing of prefixed and stem-embedded words have also implicated lexical competition during recognition (Vroomen & de Gelder, 1997; Wurm, 1997). Moreover, within-stage lateral inhibition has been considered an important part of effective information retrieval in several interactive models of lexical processing (e.g., Berg & Schade, 1992; Grainger & Jacobs, 1996; McClelland & Rumelhart, 1981; Tikkala, Eikmeyer, Niemi, & Laine, 1997). One virtue of the inhibition observed in our study is that pseudoinflections that are not so uncommon (see Table 1 for Finnish data) would not have a chance to adversely affect word recognition. Thus inhibition among the two access routes would serve a purpose in preventing unnecessary, misleading ambiguity resolution. Even though pseudoinflection had no effects on lexical access, another form of pseudoaffixation, pseudoprefixation, has been shown to affect word recognition (Lima, 1987; Pillon, 1998; Smith & Sterling, 1982; Taft, 1981). Unfortunately, there are too few true prefixes to enable a pseudoprefixation experiment in Finnish. Nevertheless, left-to-right parsing may play a role here: word-initial parts in general may acquire a special processing status because across languages they typically include the stem (Cutler, Hawkins, & Gilligan, 1985) which is the most informative portion of the letter-string. However, a left-to-right parsing effect may not be the full explanation as word-initial pseudostems do not appear to affect lexical decision (Andrews, 1986; Experiment 5 in the present study; but see Taft, 1979) or segmentshifting performance (Feldman et al., 1995; Experiment 1). It may be that a combination of two factors, word-initiality and morphological status, explains the pseudoprefixation effects observed in English and in French. Specifically, a productive grammatical (pseudo)morpheme in word-initial position could (a) induce stronger activation in its access representation than a word-final unit like pseudoinflection, which is recognized later when the full form (with its

inhibitory potential) also becomes activated, and (b) initiate a longer search for a possible meaningful interpretation than a less productive lexical unit like a word-initial pseudostem. In the present study, it was of particular theoretical interest to find that the processing cost associated with morphological ambiguity extended to pseudoambiguous noun forms (Experiment 6). This indicates that in the presence of an activated full form route, parsing of the input string into a stem and suffix is enough to activate the morpheme-based access route, and the morphophonological legality of the particular stem plus suffix combination is tested not until later. The result suggests that the morphemebased lexical organization at the level of the visual input lexicon may be simpler than some researchers have assumed. Specifically, one would not need to postulate connections between morphologically appropriate stem plus suffix combinations (see Laine et al., 1994, for a model incorporating such a structure in Finnish), which add to the complexity of the organization of the visual input lexicon. Given the rarity of pseudoambiguous forms and the overriding regularity of inflectional paradigms in Finnish, the cost in the form of delayed or erroneous recognitions would be small while the benefit in the form of simplified storage (and, as a result, perhaps also increased speed) would be considerable. Analysis of morphophonological legality (which adults are able to perform, even though variability due to dialectal and other factors exists) would thus be a fallback procedure and not part of the fast and automatic word recognition process. The present series of experiments, conducted in a little studied language that is morphologically very rich, have revealed important constraints on the workings of the morpheme-based lexical access route. These constraints are relevant to attempts to construct a general model of morphological processing (e.g., Schreuder & Baayen, 1995). First, our results indicate that when the full-form route is active, simultaneous activation of the morpheme-based route requires that there be an opportunity for parsing of the input string into a stem and a suffix. Second, the morpheme-based access route does not nec-

LEXICAL ACCESS ROUTES TO NOUNS

essarily test the morphophonological legality of the parsed stem plus suffix combination. Third, our results indicate that the relationship between the two lexical access routes is inhibitory. APPENDIX 1 The Real Word Targets Employed in Experiments 1 and 2 Pseudoinflected nouns (Type 1) TAU(1)STA background KII(1)STA dispute RII(1)STA game MILJOO(1)NA million PERSOO(1)NA person LEIJO(1)NA lion IKKU(1)NA window VAAKU(1)NA coat of arms LAKA(1)NA sheet SAATA(1)NA satan PAKI(1)NA causerie TARI(1)NA story HISTORI(1)A history AKATEMI(1)A academy ANATOMI(1)A anatomy KANSLI(1)A secretarial office ATERI(1)A meal LATTI(1)A floor KUNNI(1)A honour SAIPPU(1)A soap Inflected Nouns (Type 2) URA1STA career 1 elative case marker LOMA1STA holiday 1 elative case marker SAVO1STA Savo (proper name) 1 elative case marker VALTTI1NA trump 1 essive case marker TULKKI1NA interpreter 1 essive case marker VANKI1NA prisoner 1 essive case marker AATTO1NA eve 1 essive case marker JUTTU1NA anecdote 1 essive case marker JOULU1NA Christmas 1 essive case marker EHTO1NA condition 1 essive case marker UHKA1NA threat 1 essive case marker PALA1NA bit 1 essive case marker MUTTERI1A nut 1 partitive case marker

127

SANKARI1A hero 1 partitive case marker RAVINTO1A food 1 partitive case marker PAPERI1A paper 1 partitive case marker VAUHTI1A speed 1 partitive case marker KELLO1A clock 1 partitive case marker TAHTI1A measure (in music) 1 partitive case marker KAASU1A gas 1 partitive case marker Monomorphemic Nouns (Type 3) URHEILU sports TANSSI dance KAPPALE piece TUNNELI tunnel LUONTO nature LUOSTARI monastery TORSTAI Thursday PALATSI palace MITALI medal HEVONEN horse PERKELE devil SESONKI high season ANOPPI mother-in-law MAASTO terrain HERKKU delicacy KURSSI course TURISTI tourist NOVELLI short story MOOTTORI engine VETOOMUS appeal The Target Stimuli Employed in Experiment 3 Pseudoinflected Nouns (Type 1) INDE(1)KSI index SE(1)KSI sex TA(1)KSI taxi KAR(1)TTA map ¨ field KEN(1)TTA LAA(1)TTA slab LAU(1)TTA raft NAVE(1)TTA cow-house NUO(1)TTA seine PLANEE(1)TTA planet TEL(1)TTA tent VALUU(1)TTA currency KA(1)SSA paydesk KI(1)SSA cat MA(1)SSA mass

128

¨ NA ¨ LAINE, VAINIO, AND HYO

PRINSE(1)SSA princess JOUTSE(1)N swan MORSIA(1)N bride SIEME(1)N seed STADIO(1)N stadium Inflected Nouns (Type 2) UHKA1KSI threat 1 translative case marker TUHO1KSI havoc 1 translative case marker JONO1KSI queue 1 translative case marker AIDA1TTA fence 1 abessive case marker AKA1TTA old woman 1 abessive case marker ESTO1TTA inhibition 1 abessive case marker HUOLE1TTA worry 1 abessive case marker KITKA1TTA friction 1 abessive case marker LUVA1TTA permission 1 abessive case marker TAUO1TTA pause 1 abessive case marker VAIVA1TTA trouble 1 abessive case marker HATU1TTA hat 1 abessive case marker SUU1SSA mouth 1 inessive case marker KASA1SSA stack 1 inessive case marker PIILO1SSA hiding-place 1 inessive case marker OJA1SSA ditch 1 inessive case marker SAHA1N saw 1 genitive case marker KARJA1N cattle 1 genitive case marker MUOVI1N plastic 1 genitive case marker RUUSU1N rose 1 genitive case marker Monomorphemic Nouns (Type 3) RUHTINAS prince MAKKARA sausage VIHANNES vegetable KARITSA lamb VAARI grandfather PAKETTI parcel KEIKKA job PAASTO fast VAKKA bushel MESTARI master TELAKKA shipyard

RAUTA iron NALLE teddy bear KANAVA channel SAALIS prey TAAKKA burden SENAATTI senate KAAKAO cocoa MITALI medal ALTTARI altar The Target Stimuli Employed in Experiment 4 Stem-Embedded nouns (Type 1) ASE(1)NTO position (ASE 5 gun) ILMA(1)RI Ilmari (proper name) (ILMA 5 air) KANA(1)DA Canada (proper name) (KANA 5 hen) KARHU(1)LA Karhula (proper name) (KARHU 5 bear) KARI(1)TSA lamb (KARI 5 rock) KARJA(1)LA Karjala (proper name) (KARJA 5 cattle) KITA(1)RA guitar (KITA 5 jaws) KOIRA(1)S male (KOIRA 5 dog) KOKKO(1)LA Kokkola (proper name) (KOKKO 5 bonfire) KUKKA(1)RO purse (KUKKA 5 flower) LEHTO(1)RI lecturer (LEHTO 5 grove) SUO(1)LA salt (SUO 5 swamp) TELA(1)KKA shipyard (TELA 5 roller) TUNTU(1)RI mountain (TUNTU 5 feeling) URA(1)KKA contract (URA 5 career) VARA(1)S thief (VARA 5 reserve) VARI(1)S crow (VARI 5 warm water) VASA(1)RA hammer (VASA 5 elk calf) Inflected Nouns (Type 2) AULA1SSA assembly hall 1 inessive case HOVI1SSA court 1 inessive case marker ¨ 1SSA ¨ east 1 inessive case marker IDA IDEA1NA idea 1 essive case marker KASA1SSA stack 1 inessive case marker KEULA1A bow 1 partitive case marker KIILA1NA wedge 1 essive case marker KOLO1N hole 1 genitive case marker KOSTO1NA revenge 1 essive case marker LAKO1SSA strike 1 inessive case marker

LEXICAL ACCESS ROUTES TO NOUNS

PAAVI1N pope 1 genitive case marker PALA1NA piece 1 essive case marker PENTU1NA puppy 1 essive case marker PURO1N brook 1 genitive case marker SATO1A crop 1 partitive case marker TAHRA1N stain 1 genitive case marker TUKE1NA support 1 essive case marker VANKI1NA prisoner 1 essive case marker Monomorphemic Nouns (Type 3) ETIIKKA ethics HAARA branch KAMERA camera KORKKI cork KORTTI card LAAKSO valley LANKKU plank LONKKA hip MAKKARA sausage MATTO carpet NAAPURI neighbour PAKETTI parcel PEIKKO troll PRINSSI prince REITTI route TONTTI building lot TORPPA hut TULKKI interpreter The Target Stimuli Employed in Experiment 5 Morphologically Ambiguous Nouns (Type 1) AARI1A aria or acre 1 partitive case marker AASI1A Asia (proper name) or donkey 1 partitive case marker ROMANI1A Romania (proper name) or gypsy 1 partitive case marker EDU1STA front or benefit 1 elative case marker SIVU1STA flank or page 1 elative case marker KESKUS1TA Center Party or center 1 partitive case marker ILO1NA Ilona (proper name) or joy 1 essive case marker DIA1NA Diana (proper name) or slide 1 essive case marker KAPI1NA riot or scrabies 1 essive case marker

129

PERU1NA potato or Peru (proper name) 1 essive case marker ¨ wall or coalfish 1 essive case SEI1NA marker ¨ RI1NA ¨ vibration or color 1 essive case VA marker KAARI1NA Kaarina (proper name) or arch 1 essive case marker PORKKA1NA carrot or ski-stick 1 essive case marker HAI1TTA drawback or shark 1 abessive case marker MARJA1TTA Marjatta (proper name) or berry 1 abessive case marker LUU1TA broom or bone 1 partitive case marker MER1TA fish-trap or sea 1 partitive case marker ¨ search or view-finder 1 partiETSIN1TA tive case marker ALE1KSI Aleksi (proper name) or Ale (proper name) 1 translative case marker Inflected Nouns (Type 2) HOVI1A court 1 partitive case marker MUKI1A mug 1 partitive case marker LASI1A glass 1 partitive case marker JUNA1STA train 1 elative case marker RAO1STA slit 1 elative case marker SOLA1STA pass 1 elative case marker ¨ gesture 1 essive case marker ELEE1NA JOULU1NA Christmas 1 essive case marker SAVU1NA smoke 1 essive case marker TULKKI1NA interpreter 1 essive case marker ¨ 1NA ¨ phenomenon 1 essive case ILMIO marker TEEMA1NA theme 1 essive case marker AATTO1NA eve 1 essive case marker SEIKKA1NA fact 1 essive case marker ARMO1TTA grace 1 abessive case marker SURU1TTA sorrow 1 abessive case marker JUON1TA plot 1 partitive case marker AHVEN1TA perch 1 partitive case marker ¨ 1TA ¨ belt 1 partitive case marker VYO UHRI1KSI victim 1 translative case marker

130

¨ NA ¨ LAINE, VAINIO, AND HYO

Monomorphemic Nouns (Type 3) ROISTO villain TAULU picture PALKKA salary NYRKKI fist APOSTOLI apostle IRENE Irene (proper name) RANTA shore MARJO Marjo (proper name) TUOMARI judge ¨A ¨ RME snake KA ALANKO lowlands KOUVOLA Kouvola (proper name) LAATIKKO box VARJO shadow MINUUTTI minute ROTTA rat VAAKA weighing machine TEMPPELI temple KOSTO revenge VARTALO body The Target Stimuli Employed in Experiment 6 Pseudoambiguous Nouns (Type 1) ANTO(1)N Anton (proper name) or * issue of notes 1 genitive case marker II(1)NA Iina (proper name) or * Ii (proper name) 1 essive case marker KANTO(1)N Kanton (proper name) or * stub 1 genitive case marker KEMI(1)A chemistry or * Kemi (proper name) 1 partitive case marker LAKA(1)NA sheet or * lack 1 essive case marker LAUKA(1)A Laukaa (proper name) or * gallop 1 partitive case marker PATI(1)NA antique finish or * spavin 1 essive case marker RADO(1)N radon gas or * track 1 genitive case marker SYLVI(1)A Sylvia (proper name) or * Sylvi (proper name) 1 partitive case marker VANA(1)JA Vanaja (proper name) or * line 1 partitive case marker ¨ skin or * hippie 1 partitive case HIPI(1)A marker JANI(1)TA Janita (proper name) or * Jani (proper name) 1 partitive case marker

KARI(1)TA Karita (proper name) 1 * rock 1 partitive case marker KORO(1)NA corona or * interest 1 essive case marker LAPU(1)A Lapua (proper name) or * slip 1 partitive case marker PAKA(1)NA pagan or * pack 1 essive case marker PII(1)NA torture or * silicon 1 essive case marker SEI(1)TA Lappish god or * coalfish 1 partitive case marker UUMA(1)JA Uumaja (proper name) or * waist 1 partitive case marker VIRE(1)N Viren (proper name) or * breeze 1 genitive case marker Inflected Nouns (Type 2) APPE1NA father-in-law 1 essive case marker ¨ Iris (proper name) 1 partitive case IRIS1TA marker KANE1JA rabbit 1 partitive case marker LEO1NA Leo (proper name) 1 essive case marker LOH1TA salmon 1 partitive case marker ¨ nectar 1 partitive case marker MET1TA OLIO1NA creature 1 essive case marker ¨ KA ¨ 1A ¨ snot 1 partitive case marker RA SILPPU1A chopped straw 1 partitive case marker TENO1A Teno (proper name) 1 partitive case marker ARMI1A Armi (proper name) 1 partitive case marker JUVA1N Juva (proper name) 1 genitive case marker KYME1N Kymi (proper name) 1 genitive case marker LEPO1A rest 1 partitive case marker MEKKA1NA Mecca (proper name) 1 essive case marker NORO1NA drop 1 essive case marker PIPSA1N Pipsa (proper name) 1 genitive case marker RIESA1NA trouble 1 essive case marker TATTE1JA boletus 1 partitive case marker TUKO1N Tuko (proper name) 1 genitive case marker

LEXICAL ACCESS ROUTES TO NOUNS

Monomorphemic Nouns (Type 3) ALLI long-tailed duck KUUSAMO Kuusamo (proper name) LAKKA cloudberry LASSO lasso NAHKA leather ORION Orion (proper name) ¨ SSI ram PA ¨ KKI blanket TA TELINE stand VALMA Valma (proper name) KUOKKA hoe LAAKERI bearing LANKKU plank MATIAS Matias (proper name) NAURIS turnip PAARMA gadfly SAILA Saila (proper name) TEIPPI tape TERESA Teresa (proper name) SAARA Saara (proper name) Morphologically Ambiguous Nouns (Type 4) AARI1A aria or acre 1 partitive case marker ALE1KSI Aleksi (proper name) or Ale (proper name) 1 translative case marker DIA1NA Diana (proper name) or slide 1 essive case marker JUHA1NA Juhana (proper name) or Juha (proper name) 1 essive case marker KAPU1STA ladle or captain 1 elative case marker ¨ jingle or goat 1 essive case KILI1NA marker LUU1TA broom or bone 1 partitive case marker PORKKA1NA carrot or ski-stick 1 essive case marker SAIMA1A Saimaa (proper name) or Saima (proper name) 1 partitive case marker SAVO1TTA timberjob or Savo (proper name) 1 abessive case marker AASI1A Asia (proper name) or donkey 1 partitive case marker ARI1NA grate or Ari (proper name) 1 essive case marker

131

HAI1TTA drawback or shark 1 abessive case marker KAMELI1A camelia or camel 1 partitive case marker KARJA1A Karjaa (proper name) or cattle 1 partitive case marker KUMI1NA caraway or rubber 1 essive case marker PAPU1A Papua (proper name) or bean 1 partitive case marker ¨A ¨ 1KSI osprey or weather 1 translative SA case marker SARA1NA hinge or sedge 1 essive case marker TAIME1N trout or seedling 1 genitive case marker Inflected Nouns (Type 5) AATTO1NA eve 1 essive case marker ALMA1NA Alma (proper name) 1 essive case marker AUDI1A Audi (proper name) 1 partitive case marker ¨ viper 1 partitive case marker KYY1TA MAITO1A milk 1 partitive case marker ORPO1NA orphan 1 essive case marker PUIJO1N Puijo 1 genitive case marker SALI1A hall 1 partitive case marker SIRKUS1TA circus 1 partitive case marker VANU1KSI cotton wool 1 translative case marker AILA1A Aila (proper name) 1 partitive case marker ARMO1TTA grace 1 abessive case marker ELSA1NA Elsa (proper name) 1 essive case marker LASTI1NA load 1 essive case marker MOSKA1A trash 1 partitive case marker PATA1NA pot 1 essive case marker ROMU1KSI junk 1 translative case marker ¨ herring 1 partitive case marker SILLI1A SURU1TTA sorrow 1 abessive case marker ¨ 1NA ¨ belt 1 essive case marker VYO Monomorphemic Nouns (Type 6) ALASKA Alaska (proper name) ENERGIA energy KAMERA camera KUPOLI dome

¨ NA ¨ LAINE, VAINIO, AND HYO

132

LIESI stove MAROKKO Morocco (proper name) ORVOKKI violet SIMA mead TAIWAN Taiwan (proper name) TITTELI title EEMELI Eemeli (proper name) KAIDE banisters

KITARA guitar LENKKI loop LISKO lizard NILKKA ankle SELLI cell SOKKELI foundation TIMANTTI diamond VIIPURI Viipuri (proper name) APPENDIX 2

The Distribution of Case Inflections Employed in the Experimental Stimuli Experiment 1 Words

Nonwords

Case

Targets

Fillers

Total

% (out of 120)

Targets

Fillers

Total

% (out of 120)

nominativea elative essive partitive abessive adessive allative genitive inessive ablative

40 3 9 8 0 0 0 0 0 0

45 0 0 0 3 4 3 0 5 0

85 3 9 8 3 4 3 0 5 0

70.83 2.50 7.50 6.67 2.50 3.33 2.50 0.00 4.17 0.00

20 0 0 0 0 0 0 0 0 20

56 3 9 8 0 0 0 4 0 0

76 3 9 8 0 0 0 4 0 20

63.33 2.50 7.50 6.67 0.00 0.00 0.00 3.33 0.00 16.67

Total

60

60

120

40

80

120

a

The pseudoinflected targets are in this category.

100.0

100.0

133

LEXICAL ACCESS ROUTES TO NOUNS Experiment 2 Words

Nonwords

Case

Targets

Fillers

Total

%

Targets

Fillers

Total

%

nominativea elative essive partitive ablative adessive allative genitive illative inessive

40 3 9 8 0 0 0 0 0 0

0 0 0 0 10 10 10 10 10 10

40 3 9 8 10 10 10 10 10 10

33.33 2.50 7.50 6.67 8.33 8.33 8.33 8.33 8.33 8.33

0 0 0 0 0 0 0 0 0 0

0 10 10 10 20 20 10 10 10 20

0 10 10 10 20 20 10 10 10 20

0.00 8.33 8.33 8.33 16.67 16.67 8.33 8.33 8.33 16.67

Total

60

60

120

0

120

120

0 0 0 0 0 0 0 0

63 14 2 2 10 11 7 11

63 14 2 2 10 11 7 11

0

120

120

0 0 0 0 0 0 0 0 0

60 8 8 7 7 8 7 7 8

60 8 8 7 7 8 7 7 8

0

120

120

0 0 0 0 0 0 0 0 0 0 0

59 4 7 17 13 6 6 4 1 3 0

59 4 7 17 13 6 6 4 1 3 0

0

120

120

100.0

100.0

Experiment 3 a

nominative abessive adessive essive genitive inessive partitive translative

40 9 0 0 4 4 0 3

43 0 3 2 2 3 4 3

83 9 3 2 6 7 4 6

Total

60

60

120

nominative ablative allative essive genitive illative inessive partitive translative

36 0 0 7 4 0 5 2 0

24 8 8 0 3 8 2 5 8

60 8 8 7 7 8 7 7 8

Total

54

66

120

69.17 7.50 2.50 1.67 5.00 5.83 3.33 5.00 100.0

52.50 11.67 1.67 1.67 8.33 9.17 5.83 9.17 100.0

Experiment 4 50.00 6.67 6.67 5.83 5.83 6.67 5.83 5.83 6.67 100.0

50.00 6.67 6.67 5.83 5.83 6.67 5.83 5.83 6.67 100.0

Experiment 5 nominative abessive elative essive partitive translative adessive genitive illative inessive ambiguous

20 2 3 8 6 1 0 0 0 0 20

40 0 0 1 1 4 5 5 0 4 0

60 2 3 9 7 5 5 5 0 4 20

Total

60

60

120

a

The pseudoinflected targets are in this category.

50.00 1.67 2.50 7.50 5.83 4.17 4.17 4.17 0.00 3.33 16.67 100.0

49.17 3.33 5.83 14.17 10.83 5.00 5.00 3.33 0.83 2.50 0.00 100.0

¨ NA ¨ LAINE, VAINIO, AND HYO

134

Experiment 6 Words

nominative* abessive elative essive genitive partitive translative ambiguous Total a

Nonwords

Targets

Fillers

Total

% (out of 240)

Targets

Fillers

Total

% (out of 240)

60 2 1 13 5 17 2 20

40 12 13 0 12 29 14 0

100 14 14 13 17 46 16 20

41.67 5.83 5.83 5.42 7.08 19.17 6.67 8.33

0 0 0 0 0 0 0 0

76 17 17 27 24 61 18 0

76 17 17 27 24 61 18 0

31.67 7.08 7.08 11.25 10.00 25.42 7.50 0.00

120

120

240

0

240

240

100.0

100.0

The pseudoambiguous targets are in this category.

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