Comprehension of non-literal language: brain damage and developmental perspectives

International audienceSince the mid 20th century (Eisenson 1962; Weinstein 1964), we know that the occurrence of a right-hemisphere (RH) lesion - by contrast to a left-hemisphere lesion - can interfere with pragmatic abilities and particularly with the processing of non-literal language. Non-literal language includes any utterance that produces an apparent need to go beyond what is literally stated to apprehend speakers' communicative intent and, consequently, to understand the meaning of these utterances in a given context. Deficits affecting many aspects of non-literal language have been reported such as indirect speech acts, metaphor, idiom, humor and irony suggesting that high-level language processing is impaired in RHD individuals (e.g., Monetta & Champagne-Lavau, 2009 for a review). These pragmatic deficits, however, are not present in all RHD subjects and patterns of performance may vary from one individual to another (Champagne-Lavau & Joanette, 2010). While various hypotheses have been proposed to explain such deficits, the reasons why such a pragmatic deficit may occur following RH damage are still unclear. There are few studies concerning pragmatic deficits in young brain damaged people but they represent a large proportion of these population and they have substantial social-adaptation problems, as well as difficulties with the pragmatic aspects of language. Lesions's side and frontal lobe lesions should also be considered to understand the pragmatic profiles of brain damaged populations (Channon et al., 2007). One this point, various profiles in non-literal language comprehension (indirect request, sarcasm) have been explored with children, adolescents and young adults with frontal lesions (Dardier et al., 2006; Dardier et al., in press)