Verb Regularity Research Articles

Neural Dynamics of Processing Inflectional Morphology: An fMRI Study on Korean Inflected Verbs.

The present study aimed to elucidate the neural mechanisms underpinning the visual recognition of morphologically complex verbs in Korean, a morphologically rich, agglutinative language with inherent polymorphemic characteristics. In an fMRI experiment with a lexical decision paradigm, we investigated whether verb inflection types (base, regular, and irregular) are processed through separate mechanisms or a single system. Furthermore, we explored the semantic influence in processing inflectional morphology by manipulating the semantic ambiguity (homonymous vs. unambiguous) of inflected verbs. The results showed equivalent activation levels in the left inferior frontal gyrus for both regular and irregular verbs, challenging the dichotomy between the two. Graded effects of verb regularity were observed in the occipitotemporal regions, with regular inflections eliciting increased activation in the fusiform and lingual gyri. In the middle occipital gyrus, homonyms showed decreased activation relative to that of unambiguous words, specifically for base and irregular forms. Furthermore, the angular gyrus exhibited significant modulation with all verb types, indicating a semantic influence during morphological processing. These findings support single-system theories and the connectionist framework, challenging the assumptions of purely orthographic morphological decomposition and dual-mechanism accounts. Furthermore, they provide evidence for a semantic influence during morphological processing, with differential reliance on semantic activation for regular and irregular inflections.

A role for verb regularity in the L2 processing of the Spanish subjunctive mood: Evidence from eye-tracking

AbstractThe present study investigated the second language processing of grammatical mood in Spanish. Eye-movement data from a group of advanced proficiency second language users revealed nativelike processing with irregular verb stimuli but not with regular verb stimuli. A comparison group of native speakers showed the expected effect with both types of stimuli, but these were slightly more robust with irregular verbs than with regular verbs. We propose that the role of verb form regularity was due to the greater visual salience of Spanish subjunctive forms with irregular verbs versus regular verbs and possibly also due to less efficient processing of rule-based regular inflectional morphology versus whole irregular word forms. In any case, the results suggest that what appeared to be difficulty with sentence processing could be traced back to word-level processes, which appeared to be the primary area of difficulty. This outcome seems to go against theories that suggest that L2 sentence processing is shallow.

Psycholinguistic measures for German verb pairs: Semantic transparency, semantic relatedness, verb family size, and age of reading acquisition.

A central issue in visual and spoken word recognition is the lexical representation of complex words-in particular, whether the lexical representation of complex words depends on semantic transparency: Is a complex verb like understand lexically represented as a whole word or via its base stand, given that its meaning is not transparent from the meanings of its parts? To study this issue, a number of stimulus characteristics are of interest that are not yet available in public databases of German. This article provides semantic association ratings, lexical paraphrases, and vector-based similarity measures for German verbs, measuring (a) the semantic transparency between 1,259 complex verbs and their bases, (b) the semantic relatedness between 1,109 verb pairs with 432 different bases, and (c) the vector-based similarity measures of 846 verb pairs. Additionally, we include the verb regularity of all verbs and two counts of verb family size for 184 base verbs, as well as estimates of age of acquisition and age of reading for 200 verbs. Together with lemma and type frequencies from public lexical databases, all measures can be downloaded along with this article. Statistical analyses indicate that verb family size, morphological complexity, frequency, and verb regularity affect the semantic transparency and relatedness ratings as well as the age of acquisition estimates, indicating that these are relevant variables in psycholinguistic experiments. Although lexical paraphrases, vector-based similarity measures, and semantic association ratings may deliver complementary information, the interrater reliability of the semantic association ratings for each verb pair provides valuable information when selecting stimuli for psycholinguistic experiments.

Internal and external dynamics in language: evidence from verb regularity in a historical corpus of English.

Human languages are rule governed, but almost invariably these rules have exceptions in the form of irregularities. Since rules in language are efficient and productive, the persistence of irregularity is an anomaly. How does irregularity linger in the face of internal (endogenous) and external (exogenous) pressures to conform to a rule? Here we address this problem by taking a detailed look at simple past tense verbs in the Corpus of Historical American English. The data show that the language is open, with many new verbs entering. At the same time, existing verbs might tend to regularize or irregularize as a consequence of internal dynamics, but overall, the amount of irregularity sustained by the language stays roughly constant over time. Despite continuous vocabulary growth, and presumably, an attendant increase in expressive power, there is no corresponding growth in irregularity. We analyze the set of irregulars, showing they may adhere to a set of minority rules, allowing for increased stability of irregularity over time. These findings contribute to the debate on how language systems become rule governed, and how and why they sustain exceptions to rules, providing insight into the interplay between the emergence and maintenance of rules and exceptions in language.

Patients with impaired verb-tense processing: do they know that yesterday is past?

This paper begins with a focus on the task of stem inflection, where participants are given a verb stem and asked to produce the verb's past-tense form, which can produce a neuropsychological double dissociation with respect to regular versus irregular verbs. Two differing theoretical interpretations are outlined: one is based on specifically morphological and separate brain mechanisms for processing regular versus irregular verbs; the other argues that the two sides of the dissociation can arise from one procedure, which is not specifically morphological, and which relies to differing extents on phonological versus semantic information for regular versus irregular verbs. We then present data from a different version of the task, in which patients were given past-tense forms and asked to produce the present-tense or stem forms (talked → talk and ate → eat). This change yielded a very different pattern of performance in four non-fluent aphasic patients as a function of the regular-irregular manipulation, an outcome which is argued to be more compatible with the single- than the dual-mechanism account. Finally, we present a small amount of data from a task in which the patient was asked to judge whether spoken regular and irregular verb stems and past-tense forms indicated actions occurring today or yesterday. This task produced an even more different and intriguing pattern of performance suggesting a deficit in morpho-syntactic knowledge: not how to produce past-tense forms but what such forms mean and how that understanding interacts with verb regularity. The paper concludes with a discussion of how the research field of acquired disorders of tense processing might advance as a result of new approaches, in particular those informed by studies of developmental disorders.

Electrophysiological Evidence for the Continuous Processing of Linguistic Categories of Regular and Irregular Verb Inflection in German

A central question concerning word recognition is whether linguistic categories are processed in continuous or categorical ways, in particular, whether regular and irregular inflection is stored and processed by the same or by distinct systems. Here, we contribute to this issue by contrasting regular (regular stem, regular suffix) with semi-irregular (regular stem, irregular suffix) and irregular (irregular stem, irregular suffix) participle formation in a visual priming experiment on German verb inflection. We measured ERPs and RTs and manipulated the inflectional and meaning relatedness between primes and targets. Inflected verb targets (e.g., leite, "head") were preceded either by themselves, by their participle (geleitet, "headed"), by a semantically related verb in the same inflection as the target (führe, "guide") or in the participle form (geführt, "guided"), or by an unrelated verb in the same inflection (nenne, "name"). Results showed that behavioral and ERP priming effects were gradually affected by verb regularity. Regular participles produced a widely distributed frontal and parietal effect, irregular participles produced a small left parietal effect, and semi-irregular participles yielded an effect in-between these two in terms of amplitude and topography. The behavioral and ERP effects further showed that the priming because of participles differs from that because of semantic associates for all verb types. These findings argue for a single processing system that generates participle priming effects for regular, semi-irregular, and irregular verb inflection. Together, the findings provide evidence that the linguistic categories of verb inflection are processed continuously. We present a single-system model that can adequately account for such graded effects.

Children's Marking of Verbal –s by Nonmainstream English Dialect and Clinical Status

Children's marking of verbal -s was examined by their dialect (African American English [AAE] vs. Southern White English [SWE]) and clinical status (specific language impairment [SLI] vs. typically developing [TD]) and as a function of 4 linguistic variables (verb regularity, negation, expression of a habitual activity, and expression of historical present tense). The data were language samples from 57 six-year-olds who varied by their dialect and clinical status (AAE: SLI = 14, TD = 12; SWE: SLI = 12, TD = 19). The AAE groups produced lower rates of marking than did the SWE groups, and the SWE SLI group produced lower rates of marking than did the SWE TD group. Although low numbers of verb contexts made it difficult to evaluate the linguistic variables, there was evidence of their influence, especially for verb regularity and negation. The direction and magnitude of the effects were often (but not always) consistent with what has been described in the adult dialect literature. Verbal -s can be used to help distinguish children with and without SLI in SWE but not in AAE. Clinicians can apply these findings to other varieties of AAE and SWE and other dialects by considering rates of marking and the effects of linguistic variables on marking.

(Ir)regularity of verbs revisited

In three experiments we explored the representation and encoding of verb regularity. Contrasting articulation latencies of present and past regular and irregular forms from paradigms consisting of regular, irregular, or hybrid verbs (regular in present, but irregular in past tense), allowed us to differentiate between affixation and stem selection processes. The analyses revealed that regular verbs in the present and past tense were produced significantly faster than all other forms. Crucially, the naming latencies of hybrid and irregular verbs did not differ from each other in both tenses. We conclude that regularity is not a property of individual verb forms, but generalizes to all forms within a paradigm. In a third, picture word interference experiment, we tested whether regularity, when not bound to individual verb forms, is represented in the form of abstract regularity nodes, as assumed for gender or conjugational class. However, the critical conditions did not exhibit the expected congruency effect. Consequently we conclude that the paradigmatic effects could be explained as a result of the complexity of lexical entries. The retrieval of a complex entry (irregular and hybrid verbs) takes longer than the retrieval of a single stem entry (regular verbs).

Agrammatic production: Interpretable features and selective impairment in verb inflection

This study investigates the ability of two Greek-speaking agrammatic individuals to produce subject–verb Agreement, Tense, and Aspect in light of recent hypotheses formulated to explain the patterns of performance observed in agrammatic aphasia. The role of frequency and (morphological) regularity of verbs in agrammatism is also explored. For these investigations a sentence completion task was developed. Overall, Aspect was found significantly more impaired than Tense, and Tense significantly more impaired than Agreement. No dissociation was observed between past and future Tense, or between perfective and imperfective Aspect, for any of the two agrammatic participants. No verb regularity effect was detected and only a verb frequency effect in the Tense condition was observed for one of the participants. It is suggested that the two agrammatic participants have a morphosyntactic deficit, while one of them has an additional lexical deficit. Moreover, it is argued that the increased processing demands of Tense and Aspect, which carry interpretable features, render them more vulnerable compared to Agreement, which bears an uninterpretable feature and is a local, strictly grammatical operation. The significantly worse performance of the two agrammatic participants on Aspect than on Tense is attributed to the more “subjective” nature of the former category.

An event-related potential study of cross-modal morphological and phonological priming

The current work investigated whether differences in phonological overlap between the past- and present-tense forms of regular and irregular verbs can account for the graded neurophysiological effects of verb regularity observed in past-tense priming designs. Event-related potentials were recorded from 16 healthy participants who performed a lexical-decision task in which past-tense primes immediately preceded present-tense targets. To minimize intra-modal phonological priming effects, cross-modal presentation between auditory primes and visual targets was employed, and results were compared to a companion intra-modal auditory study (Justus, T., Larsen, J., de Mornay Davies, P., Swick, D. (2008). Interpreting dissociations between regular and irregular past-tense morphology: evidence from event-related potentials. Cognitive, Affective, Behavioral Neuroscience, 8, 178–194.). For both regular and irregular verbs, faster response times and reduced N400 components were observed for present-tense forms when primed by the corresponding past-tense forms. Although behavioral facilitation was observed with a pseudopast phonological control condition, neither this condition nor an orthographic-phonological control produced significant N400 priming effects. Instead, these two types of priming were associated with a post-lexical anterior negativity (PLAN). Results are discussed with regard to dual- and single-system theories of inflectional morphology, as well as intra- and cross-modal prelexical priming.

The On-Line Resolution of the Sentence Complement/Relative Clause Ambiguity: Evidence from Spanish

The On-Line Resolution of the Sentence Complement/Relative Clause Ambiguity: Evidence from Spanish

Production of English finite verb morphology: a comparison of SLI and mild-moderate hearing impairment.

The performance on production of finite verb morphology of 19 children (ages 5;9-10;7) with mild-moderate sensorineural hearing impairment (SNH) was compared with that of 14 children with specific language impairment (SLI) (ages 7;2-10;9) and age-matched and language-matched control groups. On average, the SNH group outperformed the SLI group and was comparable to controls. However, a subset of the SNH group (n = 6) was impaired on one or both of these tasks. Degree of hearing loss or age of receiving hearing aids was not directly related to performance, but other language measures were. The subset was also significantly younger than the rest of the SNH group, suggesting that acquisition of finite verb morphology may be delayed in children with hearing impairments. Verb regularity had no effect on performance of any group, but word frequency and phonological complexity did exert an influence. The findings are discussed in relation to causative theories of SLI.