Speech polar plots for different directionality settings of SONNET cochlear implant processor

The impact of cochlear implant microphone settings on the binaural hearing of experienced cochlear implant users with single-sided deafness

“…The head shadow effect in the SONNET group was also higher when using the omnidirectional setting than the natural setting. These findings are supported by results from De Ceulaer et al [ 17 ], who reported a median SRT in noise in a group of adults with bilateral deafness and a unilateral CI was − 5.6 dB SNR with omnidirectional, − 9.1 dB SNR with natural, and − 12.8 dB SNR with adaptive microphone. Interestingly, the benefit of using the adaptive microphone setting is so strong; it is also evident in CI users with SSD.…”

“…Again, the MD settings seem to have a strong impact on the perception of our participants, demonstrating the effectiveness of microphone filtering. When using the omnidirectional microphone, our results show that the sound signal has the potential to be equally perceived in the tested semi-circle, while using the adaptive setting restricts the area of perception (see measured polar plots [ 17 ]). Comparing the RSME in the omnidirectional setting with both groups did not show a significant difference.…”

“…Only with the SONNET and different microphone settings did the RMS error decrease (in the natural mode: 31.9° (range 19.0‒58.3°); adaptive mode: 27.3° (range 19.4‒77.9°); in the omnidirectional mode: 22.1° (range 16.6‒64.8°). This can be explained by its in-built technology [ 13 , 17 ] or the idea that binaural integration has taken place in our population. This might be due to the median hearing experience of 5 years in both groups, and that a “fair” localization process between the (acoustic) normal-hearing ear and the (electric) ear with a CI is only effective with the omnidirectional setting (when testing in a semi-circle); all other MD settings would influence the area of perception too much.…”

“…The SONNET, in contrast, has the two omnidirectional microphones, which enables microphone directionality. The three microphone modes that can be programmed by the audiologist in the SONNET are (1) “natural mode”, in which the two microphones are combined to form directionality towards the front in the higher frequencies, and omnidirectionality in the lower frequencies; (2) “adaptive mode”, in which both microphones are combined with a focus towards the front, adaptively suppressing noise from the side and from behind; and (3) “omnidirectional mode”, which provides the same directionality (or lack thereof) as previous audio processor generations (equipped with only one microphone) [ 17 ]. An overview of the corresponding polar plots can be found in the literature [ 14 , 17 ].…”

Speech Intelligibility and Spatial Release From Masking Improvements Using Spatial Noise Reduction Algorithms in Bimodal Cochlear Implant Users

“…An example of the ADM is the UltraZoom (Sonova, Stäfa, Switzerland; see Advanced Bionics, 2013 ; Buechner et al., 2014 ). Beam (Cochlear, Sydney, Australia; see Mauger et al., 2014 ) and the “Adaptive directional microphone mode” by MED-EL (Innsbruck, Austria; see De Ceulaer et al., 2019 ) which are similar in idea and implementation to the ADM. The MVDR used in this study was a fixed binaural beamformer designed to block diffuse noise sources.…”