Ironic remarks or indirect requests are part of our everyday dialogue. But certain brain lesions can alter the grasp of the hidden meaning of these expressions. During her PhD, speech therapist Natacha Cordonier studied these disorders, from diagnosis to treatment.
Exclaiming ’What a great weather! during a picnic, when the weather is rainy. Whispering ’It’s cold in here’ to ask to close the window, without expressly saying so. These two formulations illustrate the notion of non-literal language, so called when the meaning intended by the speaker does not correspond to the meaning of the words actually pronounced.
The two examples cited refer to easily identifiable practices: the first invokes irony, while the second expresses an indirect request. These are two forms of non-literal language on which Natacha Cordonier, now a post-doctoral fellow at the Institute of Logopaedic Sciences of the University of Neuchâtel (UniNE), focused during her doctoral thesis.
However, understanding these subtleties of language is not necessarily self-evident. Indeed, their comprehension can be altered in adults suffering from brain damage following a head injury or a stroke in the right hemisphere of the brain," says the doctor in speech therapy. These disorders can have important repercussions in the daily life of the affected persons, in terms of professional recovery or interactions with others. The goal of my thesis was to better understand these disorders and their causes, to develop an assessment tool to diagnose them and to create a new therapy to treat them. ’
The research involved 33 brain-damaged and 221 non-brain-damaged individuals who were presented with statements that assessed the understanding of irony and indirect requests. Comparing the performances of the participants with and without brain damage, Natacha Cordonier noted an important heterogeneity of disorders in the first group. While a third of the individuals had no difficulty understanding non-literal language, others tended to interpret all statements at face value (literal meaning) or, conversely, to see irony or indirect requests in all stories. ’
A second study focused on 221 individuals without brain damage who were asked to perform two tasks containing non-literal language to determine which performances correspond to a "normal" understanding of irony and indirect requests. This is a diagnostic tool that can be used clinically: by comparing patients’ performances to these normative data, a speech-language pathologist can determine whether or not they have non-literal language comprehension disorders.
Finally, and for the first time, a rehabilitation method was proposed to individuals who had suffered a cranial trauma. This treatment consisted of explaining by example the different forms of non-literal language (irony and indirect request in particular), then working on them with the help of written texts. The results were very positive," says the researcher. The method could be replicated in hospitals or speech therapy practices. ’
This work, carried out at the University of Neuchâtel in cotutelle with the University of Aix-Marseille, earned her the 2022 Thesis Prize awarded in France by UNADREO (National Union for the Development of Research and Evaluation in Speech and Language Therapy).
Natacha Cordonier, Understanding irony and unconventional indirect requests in individuals with right brain injury and traumatic brain injury: pathological profiles, development of an assessment tool, and management, PhD thesis, October 2021.
