Publications

The impact of second language (L2) on first language (L1), known as L2 transfer, has been suggested as a fundamental driving force of L1 attrition. The goal of this study was to test the differential attrition of verb aspect and tense in L1 (Russian) under the influence of L2 (German) grammatical properties. We also investigated whether the age of bilingualism onset and the amount of exposure to L1 modulate this L2 transfer effect.

We tested sentence processing in 30 adult Russian monolingual participants and 30 L1 attritors – Russian-German bilingual speakers – with early versus late bilingualism onset and with low versus high amounts of exposure to L1. Participants heard grammatically correct sentences, sentences with aspect violations and sentences with tense violations, and were asked to detect errors. The accuracy of participants’ responses was analysed using generalized linear mixed-effects modelling in R.

The L2 transfer effect was found, but was strongly modulated by the amount of L1 exposure: only bilinguals with little exposure to L1 showed greater attrition of L1 aspect compared to L1 tense. Moreover, the age of bilingualism onset proved to be more critical than the L2 transfer effect: an earlier bilingualism onset resulted in greater attrition of both aspect and tense in L1. The study provided new evidence about the differential impact of the grammatical similarity between L1 and L2, the age of bilingualism onset and the amount of L1 exposure on aspect and tense processing in L1 attritors.

Our findings suggest that greater L1 use after immigration helps bilingual speakers to be less susceptible to L2 transfer and prevents attrition of L1-specific grammatical categories. Also, a general decline in processing verbal morphology is more likely to occur in speakers with an early rather than a late onset of bilingualism.

People with aphasia frequently have difficulties understanding semantically reversible sentences presented in derived word order. This impairment may be related to the inconsistent processing of morphological information, as well as to difficulties inhibiting the inverse interpretation of the sentence. Studies on bilingual aphasia may contribute to our understanding of these issues by shedding light on i) differences in processing of morphology across languages; ii) enhanced control mechanisms. We studied early Basque- Spanish bilingual speakers with aphasia and monolingual Spanish speakers with aphasia, as well as unimpaired individuals. Using comparable sets of materials across languages, we combined behavioural and eye-tracking methods. Results indicate that i) at the group level, bilingual speakers perform better in Spanish than in Basque, particularly in sentences with Theme-Agent argument order. Individual case analysis shows a pattern of weak dissoci- ation across languages in several participants; ii) bilingual people with aphasia do not outperform monolingual people with aphasia in comprehension accuracy, although gaze data suggests that bilingual speakers exhibit higher inhibition and monitoring abilities.

Agrammatism in aphasia is not a homogeneous syndrome, but a characterization of a nonuniform set of language behaviors in which grammatical markers and complex syntactic structures are omitted, simplified, or misinterpreted. In a sample of 71 left-hemisphere stroke survivors, syntactic processing was quantifiedwith theNorthwestern Assessment of Verbs and Sentences (NAVS). Classification analyses were used to assess the relation between NAVS performance and morphosyntactically reduced speech in picture descriptions. Voxel-based and connectivity-based lesion-symptom mapping were applied to investigate neural correlates of impaired syntactic processing. Despite a nonrandom correspondence between NAVS performance and morphosyntactic production deficits, there was variation in individual patterns of syntactic processing. Morphosyntactically reduced production was predicted by lesions to left-hemisphere inferior frontal cortex. Impaired verb argument structure production was predicted by damage to left-hemisphere posterior superior temporal and angular gyrus, as well as to a ventral pathway between temporal and frontal cortex. Damage to this pathway was also predictive of impaired sentence comprehension and production, particularly of noncanonical sentences. Although agrammatic speech production is primarily predicted by lesions to inferior frontal cortex, other aspects of syntactic processing rely rather on regional integrity in temporoparietal cortex and the ventral stream.

This paper re-examines theoretical constructs used in the analysis of Russian word stress employing data from speakers with acquired surface dyslexia, a symptom which is characterized by an impaired lexical access and preserved grapheme-phoneme correspondence rules. Russian stems have been traditionally analysed as lexically accented or unaccented, with a default rule deriving surface stress in the latter. In the present study, we found no differences in the production of accented and unaccented stems. Instead, the analysis of errors revealed that the significant factors determining stress placement include stress neighbourhood and stress position. The speakers produced fewer errors in consistently spelled words, and there was a strong tendency to shift stress to the final syllable in consonant-final words and to the penultimate syllable in vowel-final words. These results indicate that the distributional properties play an important role in stress assignment in both accented and unaccented stem types.

A main goal of awake surgery is to preserve language in order to facilitate return to work and maintain quality of life. Although spelling has become crucial in daily life, it has received little attention in awake surgery practice. We review assessments of spelling carried out in awake surgery studies, to inspect how current neurofunctional theories of spelling may guide pre-, intra- and post-operative neurosurgical practice. A systematic database search in Embase, Medline, PubMed and Web of Science identified studies reporting on spelling assessment in glioma patients undergoing awake surgery. Twenty-three studies were included, of which only 9 report details on spelling assessments. We evaluate the incidence of dysgraphia in glioma patients, the types of spelling errors as a function of tumor location, and the specificity of spelling sites with respect to other language functions. Post-operative dysgraphia arose in 26.9% of the patients with preserved pre-operative handwriting, and persisted in 45.0% of them at follow-up. Intra-operative stimulation interfered only with handwriting in 37.7% of the patients. A network of frontal, parietal and temporal regions was found to underlie central and peripheral spelling processes. Evidence on spelling performance in patients undergoing awake surgery for gliomas is surprisingly scarce. With the limitations inherent in the small number of observations, results converge with the neurofunctional knowledge accruing from studies of stroke cases. Such knowledge should be exploited in more thorough investigations of spelling skills in glioma patients. Implications for clinical and neuroscientific practice are discussed, as well as possible strategies to overcome current limitations.

Background: Functional and usage-based theories of language are gaining increasing influence in linguistics. These theories understand language structure as underpinned by domain-general neurocognitive capacities and as shaped by usage patterns and the function of language as a means for communication. Accordingly, they entail an approach to aphasia which differs markedly from established ones based on formal theories.

Aims: Based on an outline of central claims in functional and usage-based theories, we aim to show how such theories can cast new light on aphasia.

Methods & Procedures: We focus on two strands of functional and usage-based aphasiological research: 1) research on frequency effects in aphasic speech, 2) and research on the grammatical-lexical distinction and its significance for the description of aphasic speech and the understanding of the causes of aphasia. We review available studies that fall within the two aforementioned strands of research, assessing their strengths and limitations.

Outcomes & Results: Usage-based methodologies are currently being developed that allow for fast quantification of the degree of formulaicity of a language sample and may thus be helpful in ascertaining the role of fossilized multiword expressions in aphasia. In line with central claims in usage-based linguistics, the first results of studies employing these methodologies have shown that frequency and collocation strength facilitate the retrieval of multiword expressions in a way that resembles the way in which lexical frequency facilitate retrieval of isolated words.

A recent functional and usage-based theory understands the grammatical-lexicon distinction as a means for prioritizing parts of complex linguistic messages. Defining grammatical items as items that are discursively secondary (background) and dependent on host items, this theory entails an account of grammatical deficits which bridges the gap between existing structure-oriented and processing-oriented accounts. The theory entails word-class general criteria that allow fine-grained classification of linguistic items as grammatical or lexical. Cross-linguistic studies of verb, pronoun and preposition production show that this classification is significant for the description of aphasic language.

Conclusions: Functional and usage-based studies of aphasia are still sparse, but show promising results. This approach seems especially qualified for understanding 1) the neurocognitive causes of various types of aphasia, 2) the variability across languages, communicative settings (including tasks and modalities), groups of individuals and individuals, which is characteristic of aphasic speech, and 3) the link between aphasia symptoms and the basic need and challenge for people with aphasia: to remain a social being by communicating with other social beings.

The distinction between grammatical and lexical words is standardly dealt with in terms of a semantic distinction between function and content words or in terms of distributional distinctions between closed and open classes. This paper argues that such distinctions fall short in several respects, and that the grammar-lexicon distinction applies even within the same word class. The argument is based on a recent functional and usage-based theory of the grammar-lexicon distinction (Boye & Harder 2012) and on the assumption that aphasic speech data represent the ideal testing ground for theories and claims about this contrast. A theoretically-based distinction between grammatical and lexical instances of Dutch modal verb forms and the verb form hebben was confronted with agrammatic and fluent aphasic speech. A dissociation between the two aphasia types was predicted and confirmed.

Despite a persistent interest in verb processing, data on the neural underpinnings of verb retrieval are frag- mentary. The present study is the first to analyze the contributions of both grey and white matter damage affecting verb retrieval through action naming in stroke. We used voxel-based lesion-symptom mapping (VLSM) with an action naming task in 40 left-hemisphere stroke patients. Within the grey matter, we revealed the critical involvement of the left precentral and inferior frontal gyri, insula, and parts of basal ganglia. An overlay of white matter tract probability masks on the VLSM lesion map revealed involvement of left-hemisphere long and short association tracts with terminations in the frontal areas; and several projection tracts. The involvement of these structures is interpreted in the light of existing picture naming models, semantic control processes, and the embodiment cognition framework. Our results stress the importance of both cortico-cortical and cortico-sub- cortical networks of language processing.

Polinsky and Scontras (Polinsky & Scontras), in their thought-provoking keynote article, bring together two perspectives on heritage languages, i.e., of theoretical linguistics and of psycho- linguistics, and show how they interact and enrich each other. The authors list three causes of differences (transfer from the dominant language, attrition, divergent attainment) and out- comes (avoidance of ambiguity, resistance to irregularity, shrinkage of structure) of how the heritage languages differ from their baselines, but say that they do not know whether there is “agency on the part of heritage speakers” with regards to these outcomes. In this commen- tary, we provide psycholinguistic evidence that supports Polinsky and Scontras’ idea of how important it is for psycholinguistics and the linguistic theory of heritage languages to feed each other. We show that (a) heritage speakers’ processing can diverge from the baseline in online but not offline measures, (b) transfer from the dominant language does not always hap- pen, and (c) heritage speakers can actively shape their processing that can contribute to heri- tage language restructuring in a chain reaction fashion.

Structural changes in the brain take place throughout one’s life. Changes related to cognitive decline may delay the stages of the speech production process in the aging brain. For example, semantic memory decline and poor inhibition may delay the retrieval of a concept from the mental lexicon. Electroencephalography (EEG) is a valuable method for identifying the timing of speech production stages. So far, studies using EEG mainly focused on a particular speech production stage in a particular group of subjects. Differences between subject groups and between methodologies have complicated identifying time windows of the speech production stages. For the current study, the speech production stages lemma retrieval, lexeme retrieval, phonological encoding, and phonetic encoding were tracked using a 64-channel EEG in 20 younger adults and 20 older adults. Picture-naming tasks were used to identify lemma retrieval, using semantic interference through previously named pictures from the same semantic category, and lexeme retrieval, using words with varying age of acquisition. Non-word reading was used to target phonological encoding (using non-words with a variable number of phonemes) and phonetic encoding (using non-words that differed in spoken syllable frequency). Stimulus-locked and response-locked cluster-based permutation analyses were used to identify the timing of these stages in the full time course of speech production from stimulus presentation until 100 ms before response onset in both subject groups. It was found that the timing of each speech production stage could be identified. Even though older adults showed longer response times for every task, only the timing of the lexeme retrieval stage was later for the older adults compared to the younger adults, while no such delay was found for the timing of the other stages. The results of a second cluster-based permutation analysis indicated that clusters that were observed in the timing of the stages for one group were absent in the other subject group, which was mainly the case in stimulus-locked time windows. A z-score mapping analysis was used to compare the scalp distributions related to the stages between the older and younger adults. No differences between both groups were observed with respect to scalp distributions, suggesting that the same groups of neurons are involved in the four stages, regardless of the adults’ age, even though the timing of the individual stages is different in both groups.

Disorders of language and/or communicative abilities in neurodegenerative diseases are a common phenomenon. Over the past few decades, there has been a growing interest in language performance connected to these diseases. To date, studies in the field of language impairments in Alzheimer’s disease (AD), Parkinson’s disease (PD), and frontotemporal lobar degeneration (FTLD) have focused mainly on particular aspects of language processing in the isolated disease or on comparing certain language tasks in two neurodegenerative diseases. To enable a better understanding and comparison of the underlying linguistic deficits in all three disorders, this paper focuses on phonological, semantic, and grammatical processing in each of the disorders. A review of the literature on language processing deficits reveals that phonological, semantic, and grammatical processing is impaired in the early stages of AD, PD, and FTLD, and that the underlying deficits are some- times linguistic in nature. Language disorders, however, may also reflect cognitive deficits, such as short-term verbal memory impairments, attention deficits, and reduced switching capacities, all of which have an impact on language processing.

The chapter reports the results of an auditory lexical decision task targeting morphological processing of Russian verbs. Participants included L2 learners of Russian with Advanced, Advanced High, and Superior proficiency and native speakers of Russian. The study compared the processing costs (reaction times and error rate) to citation and non-citation forms of verbs and established a processing advantage for the citation form, the infinitive, in native speakers and all L2 learner groups. These results differ from the ones reported for Russian nouns: Advanced L2 learners did not show a processing advantage for the citation form (Gor, Chrabaszcz, & Cook, 2017).

The paper discusses the preliminary data of the psychometric properties of the Token Test App - a diagnostic language impairment test (de Renzi & Faglini, 1978) implemented on a tablet.

Autism Spectrum Disorder (ASD) is a group of neurodevelopmental disorders characterized by impairments in social interaction and communication as well as behavior. Usually children with ASD have comorbid language disorders and/or delay. The present study concentrated on single-word recognition in 7-to-11-year-old Russian children with ASD. The results showed that primary-school-aged children with autism have difficulties even with such a basic process as single-word recognition.

The sensorimotor cortex is somatotopically organized to represent the vocal tract articulators, such as lips, tongue, larynx, and jaw. How speech and articulatory features are encoded at the subcortical level, however, remains largely unknown. We analyzed local field potential (LFP) recordings from the subthalamic nucleus (STN) and simultaneous electrocorticography recordings from the sensorimotor cortex of 11 human subjects (1 female) with Parkinson’s disease during implantation of deep brain stimulation (DBS) electrodes, while they read aloud three-phoneme words. The initial phonemes involved either articulation primarily with the tongue (coronal consonants) or the lips (labial consonants). We observed significant increases in high gamma (60–150 Hz) power in both the STN and the sensorimotor cortex that began before speech onset and persisted for the duration of speech articulation. As expected from previous reports, in the sensorimotor cortex, the primary articulators involved in the production of the initial consonants were topographically represented by high gamma activity. We found that STN high gamma activity also demonstrated specificity for the primary articulator, although no clear topography was observed. In general, subthalamic high gamma activity varied along the ventral-dorsal trajectory of the electrodes, with greater high gamma power recorded in the dorsal locations of the STN. Interestingly, the majority of significant articulator-discriminative activity in the STN occurred prior to that in sensorimotor cortex. These results demonstrate that articulator-specific speech information is contained within high gamma activity of the STN, but with different spatial and temporal organization compared to similar information encoded in the sensorimotor cortex.