PhD defence by Thirsa Huisman

On Thursday 11 November, Thirsa Huisman will defend her PhD thesis: "The Influence of Vision on Spatial Localization in Normal-Hearing and Hearing-Impaired Listeners"

Time: Thursday 11 November, at 14:00

Place: Building 421, aud. 71

- Zoom sign up:

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

Principal supervisor: Professor Torsten Dau
Co-supervisor: Associate Professor Ewen N. MacDonald
Co-supervisor: Dr. Tobias Piechowiak


Associate Professor Jeremy Marozeau, DTU Health Tech
Professor Steven van de Par, University in Oldenburg
Director G. Christopher Stecker, Boys Town National Research Hospital

Chairperson at defence:

Senior Researcher Jens Bo Nielsen


Hearing-impaired people have been shown to have degraded auditory localization abilities. However, it is unclear how they are affected by this in their daily life when they have access to visual information and self-motion cues that can aid localization. This thesis investigated how visual information affects spatial localization in normal-hearing and hearing-impaired people.
In a series of five experiments, this thesis demonstrated that visual information strongly influences auditory localization and found several facilitators of audio-visual integration. The probability of integration was affected by the absolute and relative stimulus positioning as well as the participant’s age. In contrast, the realism of the stimuli (i.e., using a ball and impact sound stimuli instead of a flash and noise bursts), the movement of the stimuli and hearing loss did not affect integration, at least when the stimuli were presented from the front direction. While auditory localization results of the hearing-impaired people were strongly biased towards visual information, the probability of this shift occurring was not higher in the hearing-impaired as compared to the normal-hearing people in the same age range. When the stimuli were presented from more peripheral angles (i.e., away from the front direction), auditory information more strongly influenced spatial localization. The participants were much faster at localizing auditory and audio-visual stimuli than visual stimuli, even though the participants were more accurate (but slower) at localizing visual stimuli.
These results help to better understand some of the challenges that hearing-impaired listeners face with regards to spatial localization and may guide future research on audio-visual localization in hearing-impaired and aided-hearing impaired listeners.  



Thu 11 Nov 21
14:00 - 17:00


DTU Sundhedsteknologi


Building 421, aud. 71