Duration: 1 March 2024 - 29 Februar 2028

Funding: MSCA (Marie Skłodowska-Curie Actions) Doctoral Network (Grant DOI: 10.3030/101120054)

CheriSH Project Website:  https://cherish-network.eu/

The loss of inner hair cells in the cochlear causes deafness. Since the first trial of a cochlear implant (CI) in 1957, these devices have been developed to the point where they can restore hearing and speech understanding in a large proportion of patients. Although spatial hearing is central to controlling and directing attention and to enabling speech understanding in noisy environments, it has been largely neglected in the past. In current implants, the matching of binaural information, a basic prerequisite for spatial hearing, is not yet routinely implemented. Furthermore, intensive rehabilitation programs are lacking. The EU-funded CherISH project consists of an interdisciplinary doctoral network in which physicians, psychologists and engineers collaborate, aiming at improving spatial hearing for cochlear implant users. Through twelve different interconnected projects, research will be carried out by (1) applying machine learning algorithms to identify sound sources and to provide the information to CI users through visual or tactile spatial cues, (2) examining physiological impairments of spatial hearing in CI users and matching the imbalance of the binaural inputs, and by (3) designing patient-centered training programs that make use of virtual environments. The doctoral training network will provide the next generation of researchers and engineers with a deep understanding of the multifaceted problems of spatial hearing, and equip them with expertise and skills to come up with innovative solutions in this field. The collaboration between academia and private sector will enable the realisation of new solutions for spatial hearing in CIs, thus substantially improving hearing for deaf patients. 

The project performed at ARI (DC6) will investigate how spatial hearing supports threat detection and defensive behavior. Normal-hearing listeners are able to perceive the space immediately surrounding them – termed peripersonal space (PPS) – and demarcate it from distant extrapersonal space (EPS). This demarcation is important for organisms as it distinguishes between objects we can and cannot interact with at a given moment and facilitates increased multisensory integration inside PPS. The multisensory nature of PPS representation aligns also with the phenomenon of auditory looming bias, which manifests as an increased saliency of approaching auditory objects and is more effective in capturing attention when sounds are paired with tactile or visual cues. Cochlear implants may affect both looming perception and peripersonal space representation. Is the distinction between the different portions of auditory space present or absent from CI users’ spatial representation? Does the identification of looming sounds suffer? Finally, investigating this topic in healthy newborns will allude to the potential risks of early sensory deprivation in congenitally deaf individuals and the related benefits of early implantation.