Linguistic mechanisms of coherence in aphasic and non-aphasic discourse

Background: Coherence is the quality that distinguishes discourse from a random collection of sentences. People with aphasia have been reported to produce less-coherent discourse than non-language-impaired speakers. It is largely unclear how coherence is established in natural language and what leads to its impairment in aphasia.Aims: This paper presents a cross-methodological investigation on coherence in the discourse of Russian native speakers with and without aphasia. The purpose of this study was to examine the connection between language impairments in aphasia and different aspects of discourse coherence in order to determine the linguistic mechanisms that could be involved in establishing and maintaining it.Methods &amp; Procedures: Coherence was operationalised as a combination of four aspects: informativeness, clarity, connectedness, and understandability. Twenty participants were asked to retell the content of a short movie. The retellings were annotated using Rhetorical Structure Theory (RST), a formalistic framework for discourse-structure analysis. Next, they were evaluated for coherence on a four-point scale by trained raters. The ratings were compared between groups. A classification analysis was performed to determine whether the ratings could be predicted based on the macrolinguistic variables collected from the RST annotations and several microlinguistic variables previously linked to coherence.Results: Retellings produced by speakers with aphasia received lower ratings than those of control participants on all aspects of coherence. The results indicate that different combinations of microlinguistic and discourse-structure variables play a role in establishing each of the coherence aspects.Conclusions: Our results provided supporting evidence on coherence impairment in aphasia. Perception of a discourse as more or less coherent was associated with both microlinguistic and macrolinguistic variables, with different combinations of variables relevant for each of the aspects. Furthermore, we found that discourse structure plays an important role, especially for understandability. We speculate that pragmatic knowledge shared by interlocutors may boost the coherence of aphasic discourse.</p

Discourse Diversity Database (3D) para pesquisa em linguística clínica: projeto, construção e análise

Discourse Diversity Database (3D) is a corpus designed for clinical linguistics research. It consists of oral speech samples of three different genres: picture-elicited narratives, personal stories, and picture-based instructions. The sub-sections of 3D include recordings by Russian speakers from three independent groups: people with brain tumors before and after tumor removal, people with schizophrenia, and neurologically healthy individuals. This article is devoted to the description of the data collection, the annotation scheme, and the specific characteristics of each sub-section of the corpus.O Discourse Diversity Database (3D) é um corpus desenvolvido para a pesquisa em linguística clínica. Ele consiste de amostras de fala oral de três gêneros diferentes: narrativas induzidas por imagens, histórias pessoais e instruções baseadas em imagens. As subdivisões do 3D incluem gravações de falantes de russo de três grupos independentes: pessoas com tumores cerebrais antes e depois da remoção do tumor, pessoas com esquizofrenia e indivíduos neurologicamente saudáveis. O presente artigo é dedicado à descrição do procedimento de coleta de dados, do esquema de anotação e das características específicas de cada subdivisão do corpus

A 71-Year-Old Man Presenting with Anemia and a Solitary Skin Lesion Associated with Primary Cutaneous Marginal Zone Lymphoma

A 71-year-old man with a solitary red lesion on his left arm, which initially thought to be a hematoma, was admitted for inpatient evaluation of anemia, which after a positive direct Coombs test was qualified as autoimmune hemolytic anemia. The patient also presented with hoarseness and biopsies from the swelled nasopharynx and an enlarged right tonsil were obtained. Due to uncertain diagnosis and the patient’s previous history of malignancy, (low grade lymphoproliferative lymphoma) skin and bone marrow biopsies were performed. Unfortunately, the patient’s status rapidly deteriorated as a result of septic shock. The obtained skin, nasopharynx, and tonsil biopsies became available after the patient died and showed marginal zone lymphoma with no evidence of lymphoproliferative neoplasm in the bone marrow.   &#x0D; This case demonstrates the diagnostic complexity of nodal marginal zone lymphoma complicated by severe life-threatening autoimmune hemolytic anemia in an elderly patient with multimorbidity, which presents management challenges for health care providers.</jats:p

Effect of Speaker’s Fatigue on Features of Spoken Discourse

In clinical linguistics, spoken discourse analysis is a crucial part of diagnostics as well as fundamental research of speech produced by people with various language impairments. The most common features for assessment are speech fluency, speech failures, errors, and syntactic complexity measures. However, several studies have shown that some of these parameters can be affected by fatigue or physical stress. Our study on narrative and procedural spoken discourse by healthy speakers with different levels of fatigue has shown a significant effect of fatigue level on speech tempo, and the elicitation task significantly affected multiple characteristics of spoken discourse</jats:p

Russian CliPS: a Corpus of Narratives by Brain-Damaged Individuals

Abstract In this paper we present a multimedia corpus of Pear film retellings by people with aphasia (PWA), right hemisphere damage (RHD), and healthy speakers of Russian. Discourse abilities of brain-damaged individuals are still under discussion, and Russian CliPS (Clinical Pear Stories) corpus was created for the thorough analysis of micro-and macro-linguistic levels of narratives by PWA and RHD. The current version of Russian СliPS contains 39 narratives by people with various forms of aphasia due to left hemisphere damage, 5 narratives by people with right hemisphere damage and no aphasia, and 22 narratives by neurologically healthy adults. The annotation scheme of Russian CliPS 1.0 includes the following tiers: quasiphonetic, lexical, lemma, part of speech tags, grammatical properties, errors, laughter, segmentation into clauses and utterances. Also analysis of such measures as informativeness, local and global coherence, anaphora, and macrostructure is planned as a next stage of the corpus development

Referential Choice

We report a study of referential choice in discourse production, understood as the choice between various types of referential devices, such as pronouns and full noun phrases. Our goal is to predict referential choice, and to explore to what extent such prediction is possible. Our approach to referential choice includes a cognitively informed theoretical component, corpus analysis, machine learning methods and experimentation with human participants. Machine learning algorithms make use of 25 factors, including referent’s properties (such as animacy and protagonism), the distance between a referential expression and its antecedent, the antecedent’s syntactic role, and so on. Having found the predictions of our algorithm to coincide with the original almost 90% of the time, we hypothesized that fully accurate prediction is not possible because, in many situations, more than one referential option is available. This hypothesis was supported by an experimental study, in which participants answered questions about either the original text in the corpus, or about a text modified in accordance with the algorithm’s prediction. Proportions of correct answers to these questions, as well as participants’ rating of the questions’ difficulty, suggested that divergences between the algorithm’s prediction and the original referential device in the corpus occur overwhelmingly in situations where the referential choice is not categorical