Figurative language comprehension in aphasia: A

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Figurative language comprehension in aphasia: A case study. Dorota Jaworska, Anna Cieślicka, Karolina Rataj (Adam Mickiewicz. University, Poznań, Poland).
YLMP2010 Abstract – www.ylmp.pl • www.ifa.amu.edu.pl/ylmp

References: Eckert, Penelope. 2005. Variation, convention and social meaning. (Paper presented at the Annual Meeting of Linguistic Society of America, Oakland CA, 7 Jan. 2005.) Eckert, Penelope – Sally Mcconnell-Ginet. 1999. “New Generalizations and Explanations in Language and Gender Research”, Language in Society 28: 185-201. Lave, Jean – Etienne Wenger. 1991. Situated learning: Legitimate peripheral participation. Cambridge & New York: Cambridge University Press. Wenger, Etienne. 1998. Communities of practice. Cambridge & New York: Cambridge University Press.

Figurative language comprehension in aphasia: A case study Dorota Jaworska, Anna Cieślicka, Karolina Rataj (Adam Mickiewicz University, Poznań, Poland)

Aphasia is a ”disorder of language resulting from [...] injury to the dominant cerebral hemisphere” (Marshall et al. 1998: 132). Depending on the area and extent of the damage, an individual suffering from aphasia may be able to speak but not write, or vice versa, or display any of a wide variety of deficiencies in reading, writing, and comprehension. Classical accounts of aphasia tended to envisage the traditional approach towards aphasia, as proposed by Broca (1861) and Wernicke (1874), focussing on the dissociation between speech production and perception. Thus, at first it was only the traditional linguistic levels, such as phonology, morphology, syntax and semantics, that were analysed by aphasiologists. However, aphasic patients have been demonstrated to exhibit deficits that extend beyond the domains of formal linguistics. More recent research into the phenomenon has repeatedly shown that such patients experience serious difficulties in comprehension of figurative language, such as metaphors, idioms, proverbs and irony (Nenonen et al. 2002; Gagnon et al. 2003; Papagno et al. 2004; Cacciari et al. 2006; Thoma – Daum 2006; Papagno – Caporali 2007). Interestingly, in tasks investigating participants’ ability to choose the best paraphrase of a nonliteral utterance, aphasic patients have been demonstrated to exhibit a strong bias towards the literal interpretation (Cieślicka et al. in press). The aim of the present study is to exhaustively test comprehension of various types of nonliteral discourse by an aphasic patient. For this reason, a comprehensive figurative language battery was devised. The battery was comprised of five parts, each focussing on – respectively – idioms, proverbs, similes, metaphors and irony. Moreover, the five utterance types were further subdivided into smaller categories, so that the effects of category type could be observed. The primary research question was whether the patient would make fewer mistakes in tasks involving conventional types of figurative language than in those testing novel ones. Furthermore, it was expected that the comparison of the subject's performance on different task types tapping various kinds and categories of utterances would yield interesting and insightful results, especially those concerning the processing of idioms as analysed with reference to the continua of transparency, well-formedness and plausibility. Another

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important question was whether irony, which has long been believed to be the most difficult type of figurative language, would be the most problematic one for the aphasic patient. The patient was a forty-two year old right-handed male with higher education. Initially, he was diagnosed with global aphasia, which resulted from damaged cortical and subcortical structures of the frontal, temporal and parietal lobes of both cerebral hemispheres. The etiology of the brain damage was a severe ischaemia. During the experiment, the patient was at the stage of comprehension at a single word level, and his aphasia was dynamic, that is his performance on various linguistic tasks tended to undergo rapid changes, sometimes within relatively short periods of time. The results of the study indicate that the aphasic patient had disordered figurative language comprehension. Furthermore, they provide partial support for the theory that conventional types of figurative language pose less difficulty for aphasics than novel types do. On the other hand, the study has yielded surprising results concerning the patient’s comprehension of metaphors. The damage in his right hemisphere may have contributed to the observed metaphor comprehension deficit, as a number of studies have tested the role of the right hemisphere in the processing of novel as opposed to conventional metaphoric expressions (Gagnon et al. 2003; Kacinik – Chiarello 2007). The obtained results call for further research into this issue.

References: Broca, Paul. 1861. “Remarques sur le siège de la faculté de la parole articulée, suivies d'une observation d'aphémie (perte de parole)”. [Remarks on the seat of the faculty of articulated language, following an observation of aphemia (loss of speech)], Bulletin de la Société d'Anatomie 36: 330-357. Cieślicka, Anna – Karolina Rataj – Dorota Jaworska. In press. “Figurative language impairment in aphasic patients: the effect of task type and the type of ffigurative trope”. Cacciari, Cristina – Fabiola Reati – Maria Rosa Colombo – Roberto Padovani – Silvia Rizzo – Constanza Papagno. 2006. “The comprehension of ambiguous idioms in aphasic patients”, Neuropsychologia 44, 8: 1305-1314. Eggert, Gertrude H. (ed.). 1977. Wernicke's works on aphasia: A sourcebook and a review. The Hague: Mouton. Gagnon, Louise – Pierre Goulet – Francise Giroux – Yves Joanette. 2003. “Processing of metaphoric and non-metaphoric alternative meanings of words after right- and lefthemispheric lesion”, Brain and Language 87, 2: 217-226. Kacinik, A. Natalie – Christine Chiarello. 2007. “Understanding metaphors: Is the right hemisphere uniquely involved?”, Brain and Language 100, 2: 188-207. Marshall, Randolph – Ronald M. Lazar – J.P. Mohr. 1998. ”Aphasia”, Medical Update for Psychiatrists 3, 5: 132-138. Nenonen, M. – J. Niemi – M. Laine. 2002. “Representation and processing of idioms: evidence from aphasia”, Journal of Neurolinguistics 15, 43-58. Papagno, Constanza – Patrizia Tabossi – Maria Rosa Colombo – Patrizia Zampetti. 2004. “Idiom comprehension in aphasic patients”, Brain and Language 89, 1: 226-234. Papagno, Constanza – A. Caporali. 2007. “Testing idiom comprehension in aphasic patients: The effects of task and idiom type”, Brain and Language 100, 2: 208-220. Thoma, Patrizia – Irene Daum. 2006. “Neurocognitive mechanisms of figurative language processing: Evidence from clinical dysfunctions”, Neuroscience and Behavioral Reviews 30, 8: 1182-1205.

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Wernicke, Karl. 1874. “Der aphasische symptomencomplex: Eine psychologische studie auf anatomischer basis”. [The aphasic symptom complex: A psychological study on an anatomical basis], in: Gertrude H. Eggert (ed.), 91-145.

Word recognition in dyslexia - investigating the interhemispheric transfer deficit hypothesis.

Anna Jelec (Adam Mickiewicz University, Poznań, Poland)

The corpus callosum is a bridge of neural fibers that connects the hemispheres in the human brain. In the course of brain development, it guides the lateralization process and is responsible for the patterns of arousal between the hemispheres. Several studies (Hines et al. 1992; Moore et al. 1996) and reviews (Beaton 1997) investigating the neurodevelopmental origins of dyslexia have hinted towards the role played by the corpus callosum and interhemispheric transfer in the developmental language disorder. There is reason to believe that such symptoms of developmental dyslexia as motor asynchrony (Condon 1985), a logographic strategy for word recognition - that is viewing letters as pictures - (Habib 2000: 2375) and a tendency to letter transposition may be due to an impairment in the corpus callosum and the resulting deviant interhemispheric relations. The present study sets out to investigate, whether such a claim can be supported in laboratory settings. Three healthy and one dyslexic subjects were tested on a lexical choice task based on the dichotic listening paradigm (Hugdahl 1995) devised to measure whether circumventing the corpus callosum in language processing would improve the performance of a dyslexic subject. The experiment measured the differences between the subjects' performance in control conditions and when the dichotic listening technique was utilized. During the latter stage of the experiment music was played into the participants' left ear and lexical input into the right, thus effectively supplying both hemispheres with stimuli to be processed and preventing possible right-hemisphere over-reliance. The dyslexic subject displayed shorter reaction time but increased error rate in the dichotic listening condition. This provides some evidence against the hemispheric-dominance part of the hypothesis. It can be inferred from the results that the right hemisphere may indeed play a facilitative role, or no role at all, in the processes of word recognition, as circumventing it raised the number of errors made by the dyslexic subject. Interestingly, more questions than answers arose in the course of this research. Whereas it seems to early to discard the interhemispheric transfer deficit hypothesis, the support for it does not seem substantial. What is more, the results of the study hinted at the possibility of a double dissociation between the performance of healthy and reading-impaired groups during the dichotic listening task, further research into which may provide insight into the role that both the corpus callosum and the right hemisphere play in language comprehension.

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