1. Experimental study of morphological priming: evidence from Russian verbal inflection Tatiana Svistunova Elizaveta Gazeeva Tatiana Chernigovskaya St. Petersburg State University

2. Structure of the mental lexicon Some of the major questions concerning the organization of the mental lexicon: What are the representations of the words in the mental lexicon? How are the lexical items processed, stored and accessed in the mental lexicon?

3. Inflectional morphology There is another question closely related to the previous ones:  Are the complex / inflected words stored together with their stems or as separate lexical entries? Experimental studies of inflectional morphology can provide us with the answers to this question

4. Inflectional morphology In the present study we focus on the verbal inflectional morphology. But the implications of such studies can lead us to more general conclusions about the structure of the mental lexicon as a whole.

5. Inflectional morphology Thus the aim is to find out if the opposition “regular vs. irregular inflection” is reflected in the mental lexicon. In other words: is there any difference between regularly and irregularly inflected words on the “deep” level — in our mental lexicon?

6. Structure of the mental lexicon: the main approaches: The theoretical framework for the study comes from research on the structure of the mental lexicon, which focuses predominantly on English regular and irregular past-tense inflection and on the debates between Dual-system approach (DS) Single-system approach (SS)

7. Dual-system approach The proponents of dual-system approach (e.g. Pinker and Prince (1988), Ullman (2004)) claim that there are two distinct systems of processing in our mental lexicon: Regular forms are composed by their constituents (stems and affixes) by symbolic rules.

8. Dual-system approach Full Irregular forms are retrieved from associative memory. If we need to generate a form from a nonce- word we automatically use the regular (=default) rule.

9. Single-system approach The advocates of single-system approach (e.g. Plunkett & Marchman (1993), Bybee (1995)) argue that all the word forms are stored as separate lexical entries, both regularly and irregularly inflected forms are stored in our associative memory If we need to generate a form from a nonce- word we use analogy which is developed during the subject’s language experience

10. The role of the frequency DS: if we process a regular verb, the frequency will not influence the RTs (reaction times), since in this case symbolic rules are applied automatically. If we process an irregular verb, the role of the frequency will be significant, because all the irregular forms are retrieved from associative memory; SS: according to this approach, the more frequent the verb is the faster RT it will elicit, no matter what class the verb belongs to (regular or irregular) — so the verb frequency is significant

11. Morphological priming The main idea of the priming method is that if the words / word forms are related / connected in the mental lexicon, then it should be much easier( = faster) to retrieve a form / word from the memory if it was pre- activated by the related word.

12. Morphological priming Usually the priming stimuli are presented as pairs where the first word is a prime and the second is a target. For example, we have several pairs of words:  walk — walk; walked — walk; put — walk

13. Morphological priming Obviously, the prime and the target from the first pair are stored within the same lexical entry (walk — walk), the prime and target from the third pair seem to be unrelated (morphologically and semantically — put —walk).

14. Morphological priming If we compare the RTs of this 2 pairs, we’ll certainly get faster RTs for the first pair, because the target has been already pre- activated by the previous presentation of the related prime.

15. Morphological priming Let’s look at the second pair (walked – walk). When we get the RTs for the target, we can compare it with the RTs from the 1 st and the 3 rd pair. If it’s “closer” (statistically significant) to the 1 st, then walked – walk are stored together, if to the 3 rd, then they are unrelated and stored separately.

16. Morphological priming: DS and SS predictions The proponents of these two models make different predictions about the results of the morphological priming experiments with regular and irregular verbs.

17. Morphological priming: DS predictions Regular verbs: since such forms as walked — walk are stored together and the inflected form is computed by the symbolic rules, the presentation of ‘walked’ will lead to significant priming effect (no matter how frequent the verb might be).

18. Morphological priming: DS predictions Irregular verbs: since such forms as taught — teach are stored separately, the presentation of ‘taught’ will not prime ‘teach’ as strongly as the verb itself (teach — teach). In this case frequency is what counts: if the verb is frequent it has more chances to prime the target

19. Morphological priming: SS predictions Regular and irregular verbs: there is no distinction in their processing. The most important role plays frequency: the stronger connections between the items in the associative network are the faster responses we get (no matter if it’s a regular or irregular verb).

20. Verbal inflection: data across languages The majority of the studies of regular vs. irregular inflection were conducted on English and German material. So far we have data on such languages as Norwegian, Spanish, Catalan, Italian, etc.

21. Verbal inflection: data across languages But the data are still inconclusive. Russian could provide us with important findings, since it’s the language with complex inflectional morphology with more than one regular and irregular class.

22. Russian verbal inflection According to the classification by Jacobson (1948) and his followers there are 11 verbal classes in Russian without opposition “regular” vs. “irregular”. A series of experimental works (e.g. Chernigovskaya et al. (2008) showed that there is a default “j-rule” (adding the suffix ‘-j-’ to the stem) which is applied during the processing of nonce and unfamiliar verbs.

23. Russian verbal inflection The authors propose that if the 2 rules compete (default ‘-j-’ rule and ‘non-default’) then such factors as token and type frequency are important. In other words, the authors claim that it’s not only one factor which determines everything, but their complex interaction: token and type frequency and class, productivity of the verb.

24. The present study The aim of this pilot study was to find out what is the interaction between 2 factors of frequency and verb class in the morphological priming study using Russian material.

25. The present study Also: to compare our data on Russian with the findings of the experiment on German carried out by Sonnenstuhl et al. (1999), which we took as a basis for our research. We used the same technique and made up the stimuli set according to principles used in the study).

26. Experimental material Stimuli: 20 experimental triplets with regular verbs (-aj- class) and 21 with irregular verbs (-a- class). Each triplet consisted of 3 conditions:  Identical condition: delat’ — delat’ (‘to do’ — ’to do’).  Experimental condition: delaju — delat’ (‘I do’ — ‘to do’).  Control condition: kurit’ — delat’ (‘to smoke’ — ‘to do’).

27. Experimental material All the triplets were divided into 3 classes of frequency (high, medium, low). Besides the experimental triplets the stimuli set consisted of filler pairs:  243 pairs with existing Russian verbs as primes and targets (morphologically/ semantically unrelated);  243 pairs with existing Russian verbs as primes and nonce-verbs (infinitives) as targets.

28. Experimental material Then 3 versions were constructed with only one pair from each experimental triplet (because no participant should see a verb twice).

29. Method and participants Participants: 20 native speakers of Russian (15 women and 5 men). Mean age from 18 to 45 y.o. The presentation of the stimuli set and RTs’ measurement were operated by PsyScope program (http//.psy.ck.sissa.it)

30. Method and participants Experimental task: lexical decision task “word/non-word”.  Auditory primes were immediately followed by visual targets. The measurement of the RTs began with the presentation of the target.  Subjects had to react only to the targets on the screen by pressing a button.

31. Method and participants

32. Results ANOVA with repeated measures shows that the following factors influenced RTs: condition (control, experimental or identical); token frequency (high, medium or low); verb class (-aj- vs. -a-). So we observed a priming effect.

33. Results Then two separate paired t-tests were running to compare three conditions for verbs of different classes and different frequencies. They show that the effect of partial priming (statistic difference between control and other conditions) were observed for verbs of the regular -aj- class like in Sonnenstuhl et al. (1999) and for verbs of medium and low frequency.

34. Discussion On the one hand, the fact that the different priming effects were observed for regular and irregular classes agrees with the predictions of the DS approach. On the other hand, the influence of the frequency factor agrees with the predictions of the SS approach Also our results differ from those obtained by Sonnenstuhl et al. (1999), where the data coincided with the predictions made by DS.

35. General discussion Our results show that high frequency verbs are processed faster than those of lower frequency not depending on their verb class (regular or irregular). But medium and low frequency verbs elicit faster RTs if they belong to the regular productive class. It means that our data conflict with both major models of the mental lexicon.

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