Brain trauma injury (TBI) represents a major cause of death and disability for the young adult population (Masson, 2001). Indeed, the global incidence data for the general population in France allow us to calculate that 160,000 new head injuries occur each year (Azouvi et al., 2015). The main causes are public road accidents (52%), falls, accidents at work, sport and leisure activities and physical aggression. Head trauma therefore represents, due to its number and potential consequences, a considerable public health problem. In fact, the neuropsychological after-effects that occur after a CT are very variable from one individual to another and are associated with a wide variety of cognitive, behavioural and emotional disorders. Several studies have shown that changes in emotional and social behaviour are relatively common following severe TBI and can manifest as indifference, emotional lability, poor judgement and behavioural disinhibition (Milders et al., 2003). In addition, it has been shown that people with TBI have difficulty understanding social situations and the intentions of others, which may be the cause of inappropriate social behaviour (Dimoska et al., 2010). Indeed, emotional recognition plays an essential role in interpersonal relationships. The ability to interpret emotions in the environment allows individuals to anticipate certain intentions or situations and respond appropriately (Bibby and McDonald, 2005).
Although the recognition of emotions following head injury has been the subject of numerous studies, the specific study of the processing of emotional prosody remains relatively marginal, with controversial results and studies that need to be replicated. This research therefore proposes to study the processing of emotional prosody in brain injured patients, in order to contribute to the knowledge in this field. More precisely, our study has two main objectives. The first is to study the influence of three factors on the performance of brain injured patients: the type of task (discrimination versus recognition), the semantic content of the auditory material (emotionally congruent versus non-congruent versus no semantic content), and finally the emotional valence (positive versus negative valence). We thus formulate the theoretical hypothesis according to which the capacities for processing emotional prosody in head trauma patients are expressed differently according to these three factors. Indeed, we expect that difficulties, measured against a group of control participants, will appear in the recognition task only (compared to the discrimination task). Moreover, it is expected that these difficulties will be expressed only in the condition of non-congruence of the content with the emotion conveyed (in comparison with the congruent condition and with the logatomes condition). Finally, concerning emotional valence, we expect more difficulties for the experimental group in the recognition of negative emotions (compared to positive emotions). The second objective of this study is to investigate links between performance on emotional prosody tasks and global cognitive efficiency on the one hand, and executive functioning on the other. To this end, we postulate the theoretical hypothesis that global cognitive efficiency as well as the presence of a dysexecutive syndrome will be significantly correlated with the results of tasks measuring the recognition of emotional prosody.
In conclusion, this research focused on studying the processing of emotional prosody in people with severe TBI, both quantitatively and qualitatively, thus complementing existing data in this field. People who have had a TBI present a neuropsychological profile with numerous interactions that have yet to be explored. Nevertheless, our research has confirmed that people with TBI are still able to perceive and discriminate prosodic stimuli. However, their ability to label an emotion during the perception of a prosody is significantly impaired compared to people without brain damage. However, our study cannot confirm that the disturbance in this recognition of emotional prosody is due to the semantic content of the auditory material, the valence of the emotions or the overall cognitive impairment following a TBI. In spite of this, and based on the scientific literature, we were able to put forward various new explanations such as the involvement of auditory-verbal working memory, the presence of associative auditory agnosia or the consideration of factors such as age. In short, people with TBI have scientifically recognised difficulties in processing emotional prosody, which would impact on their recognition and interpretation of interpersonal cues that are supposed to guide their behaviour and thus guarantee their social integration. It is now necessary to take into account the major challenge of social reintegration of people who have had a TBI by proposing a remediation of their social cognition capacity. Indeed, in the future, it could be our responsibility to pay particular attention, during the course of treatment for TBI, to the way in which these individuals associate the cues (visual or auditory) of their environment with concepts in memory such as emotions. This is to ensure that they are able to represent the emotional states of others and thus avoid a break with their various social circles and potential isolation.
Azouvi Philippe, Vallat-Azouvi Claire, & Aubin Ghislaine. (2015). Traumatismes crânio cérébraux. De Boeck.
Masson, F., Thicoipe, M., Aye, P., Mokni, T., Senjean, P., Schmitt, V., Dessalles, P. H., Cazaugade, M., & Labadens, P. (2001). Epidemiology of Severe Brain Injuries : A Prospective Population-Based Study. Journal of Trauma and Acute Care Surgery, 51(3), 481‑489. https://doi.org/10.1097/00005373-200109000-00010
Milders, M., Fuchs, S., & Crawford, J. R. (2003). Neuropsychological Impairments and Changes in Emotional and Social Behaviour Following Severe Traumatic Brain Injury. Journal of Clinical and Experimental Neuropsychology, 25(2), 157‑172. https://doi.org/10.1076/jcen.25.2.157.13642
Dimoska, A., McDonald, S., Pell, M., Tate, R., & James, C. (2010). Recognizing vocal expressions of emotion in patients with social skills deficits following traumatic brain injury. Journal of the International Neuropsychological Society, 16(2), 369‑382. https://doi.org/10.1017/s1355617709991445
Bibby, H., & McDonald, S. (2005). Theory of mind after traumatic brain injury. Neuropsychologia, 43(1), 99‑114. https://doi.org/10.1016/j.neuropsychologia.2004.04.027