Beneficiary: Katholieke Universiteit Leuven, Belgium
In single-sided deafness (SSD), speech perception in noisy conditions and localization, because of the temporal processing problem, are only among a few of the problems (Gransier et al. 2022). Hearing deprivation occurs in SSD because of the molecular excitatory-inhibitory mechanism and integrative aspects and it is more pronounced in the cortex since it completes maturation later (Easwar et al. 2017). Research shows that cortical abnormalities can be resolved with chronic implant use and contralateral aural preference can emerge in both auditory cortices as normally expected. Early implantation in young children with single-sided deafness can rapidly restore bilateral auditory input to the cortex needed to improve binaural hearing. Importantly, bilateral cochlear implantation without delay can protect from the development of aural preference syndrome, according to past studies (Gordon et al., 2013). After all, behavioral perception results of previous research also showed that testing in the surround sound environment revealed an improvement in performance when the cochlear implant was used in addition to the normal hearing ear. When investigating ascending pathway’s reorganization which results from SSD, ASSRs are more related to the auditory processing of temporal sound structures and encoding at different anatomical locations (Ross et al. 2005). In the current study, cortical and subcortical auditory pathway reorganization and binaural restoration of SSD children with cochlear implant will be compared with both SSD children without cochlear implant and children with normal hearing using an EEG-based study. Both the degree and hemispheric asymmetry of neural synchronization will be also investigated. This study lies in the fact that we look into functional hemispheric asymmetry concerning modulation frequency.
Supervisors: Astrid van Wieringen and Jan Wouters