Determinants of cohesion and coherence in various genres of discourse of Polish-speaking people with mixed aphasia

Background Aphasia is a disorder that seriously affects linguistic and communicative functioning. It might disturb speech comprehension, expression of grammatically correct and coherent speech, and discourse production.Aims This study aimed to investigate the hypothesis that the type of discourse influences the macro- and microstructure of the language of Polish speakers diagnosed with mixed aphasia and to demonstrate discourse-specific linguistic properties in two groups of patients compared to a neurotypical control group: patients with mixed aphasia with the motor component, and patients with mixed aphasia with the sensory component.Methods & Procedures Language samples were collected from people with mixed aphasia with a motor component (10 subjects), with a sensory component (10 subjects), and a control group (10 subjects), matched in terms of age and education. Discursive tasks (description of experiences related to the disease, description of an important life event, sequential image description, single image description, fairytale narrative, procedural discourse) were taken from the AphasiaBank protocol for discourse tasks. The discourse samples were analyzed in general terms of cohesion and coherence, the relations between these, and the influence of discourse genre on cohesion. Transcriptions of the patients’ utterances were made, which were then analyzed for the presence of the determinants of cohesion indicated by M.A.K. Halliday and R. Hasan: references, substitutions, ellipses, conjunctions, repetitions, and collocations (see Halliday & Hasan, 1976). A Polish adaptation of Van Leer and Turkstra’s English coherence scale (1999) was made, and the texts were then coded. For this purpose, the SALT (Systematic Analysis of Language Transcripts) software was used, which required specific codes to be introduced into the utterance transcripts in order to conduct the indicated analyses.Outcomes & Results It was noted that a significant determinant of cohesion is conjunctions, which for people with mixed aphasia are often an element that introduces the next utterance. The current research shows that people with mixed aphasia can achieve a higher degree of local coherence than global coherence. Our analysis shows that the statements of people with mixed aphasia is characterized by lower local and global coherence, which also reduces the occurrence of cohesion determinants in utterances, thus confirming reports from the subject literature.Conclusions There is a necessity to continue the research to show how cohesion and coherence patterns manifest in other types of aphasia in the Polish language. It is also worth conducting research that would examine the influence of the cohesion and coherence factors in other thematic discourses.