Диссертация (Experimental study of several core concepts of theoretical morphology (on the material of russian) - regularity, syncretism, markedness), страница 8

To date, PPI evidence on inflectional morphology has been scarce and onlyavailable for inflectionally impoverished English verbs in a same-different judgment task.Using PPI here in conjunction with a production task in an inflectionally rich language, wefound that functional connectivity between the left inferior frontal gyrus (LIFG) and bilateralsuperior temporal gyri (STG) was significantly greater for regular real verbs than for irregularones.

Furthermore, we observed a significant positive covariance between the number ofmistakes in irregular real verb trials and the increase in functional connectivity between theLIFG and the right anterior cingulate cortex in these trails, as compared to regular ones.Our results therefore allow for dissociation between regularity and processing difficultyeffects. These results, on the one hand, shed new light on the functional interplay withinthe LIFG-bilateral STG language-related network and, on the other hand, call for partialreconsideration of some of the previous findings while stressing the role of functionaltemporo-frontal connectivity in complex morphological processes.Keywords: fMRI, Russian, inflectional morphology, functional connectivity, psycho–physiological interactions,fronto-temporal brain network, dual-route theories, single-route theoriesINTRODUCTIONNumerous studies examine morphologically complex forms tocompare different models of inflection in the mental lexicon.

Oneof the crucial things they focus on is the distinction between regular and irregular forms. The so-called “dual route” (DR) approachassumes that the former are generated and processed by symbolic rules, while the latter stored in the lexicon, from where theycan be retrieved through associative memory mechanisms (e.g.,Pinker and Prince, 1988; Pinker, 1991; Marslen-Wilson and Tyler,1997; Orsolini and Marslen-Wilson, 1997; Clahsen, 1999; Ullman,2004).

According to the “single route” (SR) approach, all formsare computed by a single integrated system that contains no symbolic rules (e.g., Rumelhart and McClelland, 1986; MacWhinneyand Leinbach, 1991; Plunkett and Marchman, 1993; Ragnasdóttiret al., 1999; McClelland and Patterson, 2002).Behavioral studies testing DR and SR approaches analyze avariety of languages, but neuroimaging studies rely primarilyFrontiers in Human Neuroscienceon English and German data (e.g., Jaeger et al., 1996; Indefreyet al., 1997; Ullman et al., 1997; Marslen-Wilson and Tyler, 1998;Münte et al., 1999; Newman et al., 1999, 2007; Beretta et al., 2003;Sach et al., 2004; Joanisse and Seidenberg, 2005; Desai et al., 2006;Sahin et al., 2006; Oh et al., 2011).

Inflectional morphology inmorphologically richer languages like Finnish, Polish, and Arabic was examined in a number of neuroimaging studies (e.g.,Lehtonen et al., 2006; Boudelaa et al., 2010; Leminen et al., 2011;Szlachta et al., 2012). However, these studies did not compareregular and irregular forms, focusing on other problems (the distinction between inflectional and derivational morphology, therole of general perceptual and specifically linguistic complexity,etc.).In the present study, we turned to Russian, a language withrich and diverse morphology, and conducted an fMRI investigation where participants were asked to generate present tenseforms from different real and nonce (nonword) verbs and towww.frontiersin.org27February 2015 | Volume 9 | Article 36 | 1Kireev et al.A PPI study of Russian verb productionpluralize real and nonce nouns.

Addressing the problem of regularity in a morphologically rich language is important becauseone can tease apart several factors that are confounded in a language like English (while English definitely has its own advantageswith its minimalist system and sharp contrasts between inflectional classes). To give one example, all regular past tense formsare morphologically complex in English, i.e., contain a stem and asuffix (-ed), while irregular forms are morphologically simplex.In Russian, all past tense forms are morphologically complex,which gives us an opportunity to find out whether the effectsobserved in English were due to regularity or to morphological complexity.

Other properties of Russian that may be relevantfor the debate will be pointed out in Section “A Brief Description of the Russian Verb and Noun Systems.” We opted for aproduction task because it was used in the majority of neuroimaging studies focusing on regular vs. irregular inflectionalmorphology.Experimental data reflecting the localization and the directionof the change in functional activity are reported in Slioussar et al.(2014). In this paper, we present a ROI-whole brain voxel-wiseanalysis of context dependent changes in functional connectivity [a psychophysiological interaction (PPI) analysis; Gitelmanet al., 2003]. The first type of analysis makes it possible to revealfunctionally segregated brain areas that change their activity inresponse to experimental manipulations, while PPI is a measureof functional connectivity, which provides complementary information showing how these segregated brain areas are integrated(Friston, 2011).

Although PPI analysis does not make it possible toinfer causal relationships, it gives an opportunity to observe howthe functional interplay between involved brain regions is changedas a function of the psychological context.Therefore, we saw PPI analysis as a valuable tool to approachthe problem from a new angle, especially given the fact that wefound only one previous PPI study of inflectional morphology(Stamatakis et al., 2005). Important similarities and differencesbetween Stamatakis et al.’s (2005) findings and our results offera novel perspective on our findings from Slioussar et al. (2014),the account proposed by Stamatakis et al.

(2005) and a number ofproblems discussed in other studies.A BRIEF DESCRIPTION OF THE RUSSIAN VERB AND NOUN SYSTEMSThe Russian verb system is very complex, and there are severalapproaches to dividing verbs into classes. According to the onedeveloped in Jakobson (1948), Townsend (1975) and Davidsonet al. (1996), Russian has 11 verb classes and several so-calledanomalous verbs.

Ten classes are identified by their suffixes, whilethe 11th class has a zero suffix, and is subdivided into subclassesdepending on the quality of the root-final consonant [Jakobson (1948) and Townsend (1975) counted them as 13 separateclasses].All verbs have two stems: the present/future tense stem and thepast tense stem. Depending on the class, the correlation betweenthem may include truncations or additions of the final consonantor vowel, stress shifts, suffix alternations, alternations of stemvowels, and stem-final consonants. The verb class also determineswhich set of endings is used in the present and future tense (firstand second conjugation types).

Usually, the class is unrecoverableFrontiers in Human Neurosciencefrom a particular form. For example, délat’ ‘to do’ belongs to theAJ class, and its third person plural present tense form is délaj-ut (-j- suffix is added, first conjugation type).1 Pisát’ ‘to write’belongs to the A class, and its third person plural present tenseform is píš-ut (-a- suffix is truncated, first conjugation type, finalconsonant alternation, stress shift).

Deržát’ ‘to hold’ belongs tothe ZHA class, and its third person plural present tense form isderž-át (-a- suffix is truncated, second conjugation type).Verb classes dramatically differ in frequency, and five of themare productive. Thus, there is no single productive pattern that canbe applied to any stem irrespective of its phonological characteristics, and no obvious division into regular verbs (RVs) and irregularverbs (IVs) in this system. In our fMRI experiment, we decidedto look at the two poles of this system, comparing verbs from themost frequent and productive AJ class to verbs from small unproductive classes (we reasoned that if any differences between thesetwo groups were found, we could compare them to other verbs insubsequent studies).

For the sake of brevity, we will further callthese groups regular and irregular.Russian nouns are inflected for number and case and are classified into different declensions depending on the set of theirnumber and case endings. In many ways, this system is simplerthan the system of verb classes. There are only three declensions (plus a group of nouns with adjectival endings, severalexceptional cases and a number of uninflected nouns). Thesedeclensions differ in frequency, but all three are productive.

Usually, the declension can be unambiguously determined from thenominative singular form. Inside every declension there are smallgroups of nouns with minor irregularities: unusual endings insome forms or stem alternations. For our study we selected agroup of nouns that lose the last vowel of the stem in many formsincluding the nominative plural form (e.g. koster ‘fire’ – kostry)and a group where the stem never changes, as in the majorityof Russian nouns (e.g., šofer ‘driver’ – šofery). We will furthercall the first group irregular, although this is a relatively minorirregularity.PREVIOUS STUDIES TESTING THE SR AND DR APPROACHES ONRUSSIANBehavioral studies testing SR and DR approaches on Russianlooked at adult native speakers, L1 and L2 learners and subjects with various neurological and developmental deficits (e.g.,Gor and Chernigovskaya, 2001, 2003, 2005; Gor, 2003, 2010;Chernigovskaya et al., 2007; Svistunova, 2008; Gor et al., 2009; Gorand Jackson, 2013).

Participants were provided with infinitives orpast tense forms of real or nonce verbs and prompted to generate first person singular and third person plural present tenseforms. The findings did not unambiguously support either DR orSR approach. For example, on one hand, adults were shown touse the most frequent AJ class pattern as the default one, althoughRussian has several highly frequent productive verb classes.

Inparticular, it was often applied to nonce verbs irrespective oftheir morphonological properties. On the other hand, childrenconsecutively overgeneralize several conjugational patterns in the1 There are several ways to transliterate Russian words from Cyrillic to Latin alphabet.In this paper, we use the so-called scholarly transliteration system.www.frontiersin.org28February 2015 | Volume 9 | Article 36 | 2Kireev et al.A PPI study of Russian verb productioncourse of acquisition. As a result, the group of authors workingon Russian argued that Yang’s (2002) model relying on multiple rules of different status might be better suited to account fortheir findings. A similar model for Russian was developed by Gor(2003).Subtractive analysis of the data from the present experiment wereported in Slioussar et al. (2014) is the only fMRI study of Russianinflectional morphology we are aware of.