Auditory Perception

The aim of the ETERNEL project will be to study the influence of the perception of a single sound timbre on the understanding of a complex sound scene in hearing-impaired people with hearing aids. This will be done by quantifying the inability to manage a complex sound scene as a function of the timbre of the sounds making it up. The more a sound interferes with understanding the complex sound scene, the more salient that sound is considered to be. In this way, the investigators can determine which timbre dimensions make sounds particularly salient for the hearing impaired.

Auditory sound localization is the ability to identify the position of a sound source in space. It is defined into 3 dimensions: by its position in azimuth, elevation and distance. If it is difficult to localize a sound source, it is possible to remove the localization ambiguity by interacting with the environment, in particular by changing one's position in relation to the source (e.g. by changing the orientation of the head). Patients with schizophrenia have difficulties to localize and discriminate sounds in space but it is still poorly explored. Additionally, deficits in auditory localization could underlie difficulties in source-monitoring (i.e., distinguish the source/origin of the information) reported in schizophrenia or deficits in auditory externalization (i.e., perception of sound outside the head). Furthermore, schizophrenia is characterized by cerebral abnormalities in the auditory cortex, manifesting as auditory processing disorders at different stages of the pathology. Auditory localization may therefore be impaired from the onset of a first psychotic episode (FEP). This early phase of the disease is also referred to as the "critical" period, as the chances of remission are highest and the response to treatment is best. However, the three-dimensional aspect of auditory perception and the behavioral exploration strategies used to localize a sound in the early stages of schizophrenia are still little studied.

The COMPRESSED project is a descriptive, bi-centric and non-invasive study carried out by the CERIAH - IDA - Institut Pasteur and the Haute École Léonard de Vinci in Brussels on volunteer participants identified in two groups : * be subject to high exposure to compressed sound, as defined by professional participation in events on broadcast platforms using sound signal processing systems, over the last 3 years, * be subject to moderate or limited exposure to compressed and manipulated sound, equivalent to that of a student following certain distance learning courses. on a videoconferencing platform, alternating with other face-to-face courses, with the ability to listen during breaks, which have been taught for a maximum of 2 years. The main objective of the COMPRESSED study is to evaluate the auditory effects of exposure to manipulated sounds (compression, filtering, equalisation, accentuation, etc.) from sound distribution platforms on the auditory system of participants who are regularly exposed to these sounds as a result of their professional activity.