Background: Binaural hearing is key to listening in real environments, and yet, the functional performance of children with bilateral cochlear implants is usually assessed for each ear separately. One reason for this may be the limited space and equipment available to clinics. The BEARS project has developed among other assessments, a virtual-audio version of the Spatial Speech-in-Noise Test, the SSiN-VA. This test potentially provides a measure of speech discrimination, spatial release from masking (SRM), listening effort, and relative sound-source localisation. For SSiN-VA to be adapted for clinical use, it is necessary to assess how children’s age affects the ability of SSiN-VA to capture SRM and listening effort.

Methods: SSiN-VA provides word-identification scores for each hemifield, for trials where the noise source is close to the speech source, and for trials where the noise source is far from the speech source. It is possible to calculate an index of word identification for each hemifield, considering performance for each noise location. Asymmetries in these indexes across hemifields in SSiN-VA are thought to capture asymmetries in SRM across ears. To assess how age affects the relationship between SSiN-VA and SRM, we will assess whether the SSiN-VA speech discrimination index differences can be predicted by performance in the Spatial ASL task, which uses a traditional SRM paradigm, and whether predictions are affected by listener age. To assess whether SSiN-VA captures listening effort, we will assess whether SSiN-VA reaction time can be predicted by the outcome of the Vanderbilt Fatigue Scale, on the assumption that greater listening effort, leading to greater reaction times, will be associated with greater listening fatigue in daily life. The effect of age on these predictions will be assessed.

Results: Outcomes for 120 children from 14 UK cochlear-implant departments indicate that, overall, the group can perform the test, obtaining similar profiles as cochlear-implant users previously assessed using an array of loudspeakers. The SSiN-VA speech discrimination index difference is not correlated with the ASL SRM difference across ears for the group (S=334318, p = 0.08, rho = –0.16). Analyses about the impact of age on this relationship and on the relationship between SSiN-VA reaction time and listening effort/fatigue will be available at the time of the conference.

Discussion and conclusion: Current assessments performed in the clinic do not generally capture spatial listening. However, this dimension is key to daily communication in real-world environment. The BEARS project has developed research tools to assess speech discrimination, SRM, listening effort, and relative localisation using simple equipment and no additional space requirements in clinic. However, it is necessary to ensure that these tools are accessible to a wide range of children beyond the study population. The effect of age on performance needs to be evaluated in order to guide adaptations of the current research tools for general clinical practice.