PhD defence by Jonathan Regev

On Friday 24 May, Jonathan Regev will defend his PhD thesis "Effects of age and hearing loss on amplitude modulation processing and perception ".

Time: 09:30

Place: Building 341, auditorium 21 & zoom:  https://dtudk.zoom.us/meeting/register/u50vcu2vrTMrGtwjonkJfWjRMn0lPkoaWHMQ

Please be aware that the PhD defense may be recorded - This will also be informed at the beginning of the PhD defense.

Supervisor: Professor Torsten Dau

Co-supervisor: Dr. Helia Relaño-Iborra

Dr. Johannes Zaar, Eriksholm Research Centre

Assessment committee:
Associate professor Bastian Epp, DTU Health Tech

Professor Christian Lorenzi, Ecole normale superieure, Paris Sciences et Lettres University

Research Associate Professor Magdalena Wojtczak, University of Minnesota

Chairperson:
Associate Professor Tobias May, DTU Health Tech

Abstract:
Understanding and accurately recognizing surrounding sounds, particularly speech, is crucial for effective daily communication. However, hearing loss and advancing age often disrupt the function of the auditory system, leading to perceptual difficulties, especially in noisy environments. Despite recognizing these challenges, pinpointing the exact factors contributing to auditory perception issues remains complex. One avenue for exploration lies in delving into the processing and perception of the temporal envelope of sounds, referred to as amplitude modulations, which denotes the relatively slow fluctuations in sound amplitude. This thesis presents four behavioral studies exploring how age and hearing loss impact amplitude modulation perception and, consequently, speech intelligibility. In particular, the thesis focused on investigating modulation frequency selectivity, a central characteristic of the auditory system’s temporal processing that can be functionally described as an array of modulation filters.
The findings showed a loss of modulation selectivity solely due to age. Furthermore, opposite effects of age and hearing loss on modulation selectivity were found, with hearing loss resulting in an effective perceptual benefit. However, both age- and hearing loss-related effects were anticipated to negatively impact speech intelligibility. To explore this potential consequence, speech intelligibility in noise was assessed. Although the results aligned with the idea that the effects of age and hearing loss on modulation frequency selectivity contribute to speech intelligibility challenges, establishing a direct link remained elusive.
Overall, this thesis adds to the growing body of evidence indicating a change in temporal processing and perception among older adults, both with and without hearing loss, which may underlie the challenges experienced in speech intelligibility.